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--- test-and-measurement:analog-discovery-pro-3x50:smart-lamp [2022/05/10 12:18] – [Creating a Module for the Pmod BLE] Álmos Veres-Vitályos
+++ test-and-measurement:analog-discovery-pro-3x50:smart-lamp [2022/10/04 11:38] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== Building a Battery Powered Smart Lamp with the Analog Discovery Pro (ADP3450/ADP3250) ======
+~~TechArticle~~
+{{ :test-and-measurement:analog-discovery-pro-3x50:app_front.jpeg?200 |}}
+<WRAP group>
+In this guide, the processes of designing and building a battery-powered, Bluetooth-connected RGB lamp will be presented. The Analog Discovery Pro in Linux mode will be used to control the final project and to debug the external circuits during the testing stage. To make sure that you have the latest Linux image running on your device, follow this guide: [[test-and-measurement:analog-discovery-pro-3x50:recover-linux-mode|]]
+</WRAP>
+----
+===== Planning =====
+<WRAP group>
+Before starting designing the lamp, the goals of the project must be established. The central component of the lamp is an RGB LED which should be switched on/off via an application running on a phone. Communication with the phone can be resolved using Bluetooth or Bluetooth Low Energy, but the Low Energy variant (BLE) can be easier to use in some cases, due to the custom service characteristics (more on this later). The application should also display the ambient light conditions to notify the user to turn off the lamp if it isn't needed (automatic switching may be implemented if needed). To power the lamp, a battery can be used which can be charged from the Analog Discovery Pro (the lamp can't be directly powered from the ADP, as it doesn't provide enough current).
+In this prototype, a 5 mm RGB LED will be used as the lamp, which is powered by an old phone battery, but the circuit can be scaled for higher power lamps if needed. Communication with the phone is resolved by the [[pmod:pmodble:start|]] (Bluetooth Low Energy) module and ambient light measurements are performed by the [[pmod:pmodals:start|]] (Ambient Light Sensor). The [[pmod:pmodda1:start|]] (Digital to Analog Converter) and the [[pmod:pmodod1:start|]] (Open Drain MOSFETs) will be used in the control circuit. A full inventory of the components needed is listed below.
+</WRAP>
+----
+===== Inventory =====
+<WRAP group><WRAP half column>
+== Hardware ==
+  * [[test-and-measurement:analog-discovery-pro-3x50:start|Analog Discovery Pro (ADP3450/ADP3250)]]
+  * a smartphone with Android
+  * [[pmod:pmodble:start|]]
+  * [[pmod:pmodals:start|]]
+  * [[pmod:pmodda1:start|]]
+  * [[pmod:pmodod1:start|]]
+  * Lithium-Polymer (LiPo) battery cell
+  * RGB LED
+  * USB-A to Micro-USB cable
+  * [[https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/EVAL-ADALP2000.html#eb-overview|ADALP2000 Analog Parts Kit]]
+    * USB connector
+    * LT3092 programmable current source
+    * OP484 operational amplifier
+    * 5mm LED
+    * 470Ω resistor
+    * 3x 100Ω resistor
+    * 47Ω resistor
+    * 10Ω resistor
+</WRAP><WRAP half column>
+== Software ==
+  * [[software:waveforms:waveforms-3:start]] (for debugging)
+  * [[https://code.visualstudio.com/|Visual Studio Code]], or any other editor of your choice
+  * a web browser
+**Note:** //WaveForms can be installed by following the [[software:waveforms:waveforms-3:getting-started-guide]].//
+</WRAP></WRAP>
+----
+===== Creating a Hardware Abstraction Layer (HAL) for the Analog Discovery Pro =====
+<WRAP group>
+A Hardware Abstraction Layer (HAL) is a layer in programming that takes the functions controlling the hardware and makes them more abstract, by generalizing them. In this case, the hardware, the Analog Discovery Pro, is controlled using WaveForms SDK, from a Python script. WaveForms SDK requires a fair amount of stuff to happen to start using an instrument. The SDK uses the ctypes module and most instruments need several initialization functions (like dummy read/write functions in the case of some digital communication protocols) before using them. As the current project uses several instruments, some sort of module is needed to make the interaction with the hardware more straightforward. In the following, a Python module will be created, which is based on WaveForms SDK and works like an instrument driver for the Analog Discovery Pro. If you are not interested in the details of this module, skip to the next section. The library containing the modules can be downloaded here: {{ :test-and-measurement:analog-discovery-pro-3x50:waveforms_hal.zip |waveforms_hal.zip}}.
+</WRAP>
+<WRAP center round important 60%>
+In the attached package, not all the functions were tested, so errors might appear in some cases. Use the package responsibly and feel free to modify it.
+</WRAP>
+<WRAP group>
+Create a new folder and copy the **dwfconstants.py** file into it from WaveForms' installation path (usually //C:\Program Files (x86)\Digilent\WaveFormsSDK\samples\py\dwfconstants.py//). This file is needed as it contains all the constants needed for every instrument. Now create an initializer file and separate files for every instrument you want to use.
+--> Wrapper: __init__.py #
+<WRAP group><WRAP half column>
+This file imports all the other modules and also gives a name to each one of them. Global initialization and cleanup functions are also implemented here.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" WRAPPER """
+# import every submodule
+from WaveForms_HAL import WaveForms_HAL_Device as device
+from WaveForms_HAL import WaveForms_HAL_Supply as supply
+from WaveForms_HAL import WaveForms_HAL_Scope as scope
+from WaveForms_HAL import WaveForms_HAL_Wavegen as wavegen
+from WaveForms_HAL import WaveForms_HAL_Logic as logic
+from WaveForms_HAL import WaveForms_HAL_Pattern as pattern
+from WaveForms_HAL import WaveForms_HAL_Pattern_static as static_pattern
+from WaveForms_HAL import WaveForms_HAL_Static as digital
+from WaveForms_HAL import WaveForms_HAL_SPI as spi
+from WaveForms_HAL import WaveForms_HAL_UART as uart
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+# synchronize submodules
+def initialize():
+    # connect to the device
+    if device.connected != True:
+        device.open()
+        # copy device handles
+        supply.hdwf = device.hdwf
+        scope.hdwf = device.hdwf
+        wavegen.hdwf = device.hdwf
+        logic.hdwf = device.hdwf
+        pattern.hdwf = device.hdwf
+        digital.hdwf = device.hdwf
+        spi.hdwf = device.hdwf
+        uart.hdwf = device.hdwf
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    # close the device
+    if device.connected:
+        # reset all instruments
+        supply.reset()
+        scope.reset()
+        wavegen.reset()
+        logic.reset()
+        pattern.reset()
+        static_pattern.reset()
+        digital.reset()
+        spi.reset()
+        uart.reset()
+        device.close()
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> General: WaveForms_HAL_Device.py #
+<WRAP group><WRAP half column>
+This file contains functions used for opening and closing the device and error checking. A flag showing the current connection status is also included here.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" MAIN FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+connected = False   # the current state of the device
+"""-------------------------------------------------------------------"""
+""" ERROR CHECKING """
+"""-------------------------------------------------------------------"""
+def check_error():
+    # check for errors
+    errno = c_int()  # variable for error number
+    dwf.FDwfGetLastError(errno)  # get error number
+    # if there is an error
+    if errno != dwfercNoErc:
+        szerr = create_string_buffer(512)   # variable for the error message
+        dwf.FDwfGetLastErrorMsg(szerr)  # get the error message
+        print(str(szerr.value))  # print the error message
+        quit()  # terminate the program
+    return
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def open():
+    # open the first connected device
+    dwf.FDwfDeviceOpen(c_int(-1), byref(hdwf))
+    # if there is a problem
+    if hdwf.value == hdwfNone.value:
+        # check for errors
+        check_error()
+    connected = True    # set connection flag
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    dwf.FDwfDeviceClose(hdwf)   # close the device
+    connected = False   # set connection flag
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Logic Analyzer: WaveForms_HAL_Logic.py #
+<WRAP group><WRAP half column>
+This file contains functions controlling the logic analyzer. Besides the initialization and cleanup functions, the most important one is the receive_data() function, which reads the states of the digital I/O lines in a buffer according to the initialization parameters. The function accepts a parameter that specifies whether data specific to a digital I/O line should be selected from the dataset or not.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" DIGITAL INPUT FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import numpy
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+data_count = 8192   # buffer size
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(base_frequency=100e06, buffer_size=8192):
+    global data_count
+    data_count = buffer_size
+    # set internal clock frequency
+    internal_frequency = c_double()
+    dwf.FDwfDigitalInInternalClockInfo(hdwf, byref(internal_frequency))
+    dwf.FDwfDigitalInDividerSet(hdwf, c_int(
+        int(internal_frequency.value / base_frequency)))
+    # set 16-bit sample format
+    dwf.FDwfDigitalInSampleFormatSet(hdwf, c_int(16))
+    # set buffer size
+    dwf.FDwfDigitalInBufferSizeSet(hdwf, c_int(buffer_size))
+    return
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfDigitalInReset(hdwf)    # reset the logic analyzer
+    return
+"""-------------------------------------------------------------------"""
+""" RECEIVE ALL DATA """
+"""-------------------------------------------------------------------"""
+def receive_data(channel=None):
+    # begin acquisition
+    dwf.FDwfDigitalInConfigure(hdwf, False, True)
+    while True:
+        status = c_byte()
+        dwf.FDwfDigitalInStatus(hdwf, True, byref(status))
+        if status.value == stsDone.value:
+            # exit loop when finished
+            break
+    # get samples
+    buffer = (c_uint16 * data_count)()
+    dwf.FDwfDigitalInStatusData(hdwf, buffer, 2 * data_count)
+    buffer = numpy.fromiter(buffer, dtype=numpy.uint16)
+    buffer = buffer.tolist()
+    # break out for every pin
+    result = [[] for _ in range(16)]
+    for data in buffer:
+        for index in range(16):
+            result[index].append(data & (1 << index))
+    # return only what is necessary
+    if channel != None:
+        return result[channel]
+    else:
+        return result
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Pattern Generator: WaveForms_HAL_Pattern.py #
+<WRAP group><WRAP half column>
+The most important part of this file is the function that generates the required signal on the required channel according to the input parameters.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" DIGITAL OUTPUT FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import WaveForms_HAL.WaveForms_HAL_Static as digital
+import math
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+# function types
+class type:
+    pulse = DwfDigitalOutTypePulse
+    custom = DwfDigitalOutTypeCustom
+    random = DwfDigitalOutTypeRandom
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfDigitalOutReset(hdwf)    # reset the pattern generator
+    return
+"""-------------------------------------------------------------------"""
+""" GENERATION """
+"""-------------------------------------------------------------------"""
+def generate(channel, frequency, function, duty_cycle=50, data=None):
+    # reset pin
+    digital.stop(channel)
+    # get internal clock frequency
+    internal_frequency = c_double()
+    dwf.FDwfDigitalOutInternalClockInfo(hdwf, byref(internal_frequency))
+    # get counter value range
+    counter_limit = c_uint()
+    dwf.FDwfDigitalOutCounterInfo(hdwf, c_int(0), 0, byref(counter_limit))
+    # calculate the divider for the given frequency
+    divider = int(math.ceil(internal_frequency.value /
+                  frequency / counter_limit.value))
+    # calculate counter steps to get the required frequency
+    steps = int(round(internal_frequency.value / frequency / divider))
+    # calculate steps for low and high parts of the period
+    high_steps = int(steps * duty_cycle / 100)
+    low_steps = int(steps - high_steps)
+    # enable the respective channel
+    dwf.FDwfDigitalOutEnableSet(hdwf, c_int(channel), c_int(1))
+    # set output type
+    dwf.FDwfDigitalOutTypeSet(hdwf, c_int(channel), function)
+    # set frequency
+    dwf.FDwfDigitalOutDividerSet(hdwf, c_int(channel), c_int(divider))
+    if function == type.pulse:
+        # set duty cycle
+        dwf.FDwfDigitalOutCounterSet(hdwf, c_int(
+            channel), c_int(low_steps), c_int(high_steps))
+    elif function == type.custom:
+        # format data
+        buffer = (c_ubyte * ((len(data) + 7) >> 3))(0)
+        for index in range(len(data)):
+            if data[index] != 0:
+                buffer[index >> 3] |= 1 << (index & 7)
+        # load data
+        dwf.FDwfDigitalOutDataSet(hdwf, c_int(
+            channel), byref(buffer), c_int(len(data)))
+    # start generating the signal
+    dwf.FDwfDigitalOutConfigure(hdwf, c_int(1))
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Static Pattern Generator: WaveForms_HAL_Pattern_static.py #
+<WRAP group><WRAP half column>
+Due to hardware limitations, if one instrument is initialized which uses a certain hardware part (like the digital I/O lines), all the other instruments which use the same hardware lose control over it, so, for example, the pattern generator, the UART master, and the SPI master instruments can't be used at the same time. However, the digital I/O lines still can be controlled in a static way, by using bitmasks.
+To make use of this possibility, this library realizes the pattern generator functions using the static I/O instrument instead of the pattern generator. While this module can be used at the same time as other digital instruments, it has a very limited speed, which is not enough for the scope of this project.
+The current version of this module uses multithreading to realize several operations in parallel (actually the processor just switches very fast between the tasks).
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" DIGITAL OUTPUT FUNCTIONS """
+# import necessary modules
+import WaveForms_HAL.WaveForms_HAL_Static as digital
+import time
+import threading
+import random
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# list for processes
+processes = [None, None, None, None,
+             None, None, None, None,
+             None, None, None, None,
+             None, None, None, None]
+# class containing all channel parameters
+class channel_data:
+    frequency = None
+    duty_cycle = None
+    signal_data = None
+    function_type = None
+    thread = None
+    stop = None
+# function types
+class type:
+    pulse = 0
+    custom = 1
+    random = 2
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # stop all threads
+    for index in range(16):
+        stop(index)
+    # reset the instrument
+    digital.reset()    # reset the pattern generator
+    return
+"""-------------------------------------------------------------------"""
+""" STOP GENERATION """
+"""-------------------------------------------------------------------"""
+def stop(channel):
+    global processes
+    # stop the generation
+    if processes[channel] != None:
+        processes[channel].stop = True
+        processes[channel].thread.join()
+    processes[channel] = None
+    # reset the pin
+    digital.stop(channel)
+    return
+"""-------------------------------------------------------------------"""
+""" SET GENERATION DATA """
+"""-------------------------------------------------------------------"""
+def generate(channel, frequency, function, duty_cycle=None, data=None):
+    global processes
+    # stop running thread
+    if processes[channel] != None:
+        stop(channel)
+    # set pin as output
+    digital.set_output(channel)
+    # save current channel data
+    current_ch = channel_data()
+    current_ch.frequency = frequency
+    current_ch.duty_cycle = duty_cycle
+    current_ch.signal_data = data
+    current_ch.function_type = function
+    current_ch.stop = False
+    current_ch.thread = threading.Thread(target=channel_handler, args=(channel,))
+    # update data table
+    processes[channel] = current_ch
+    # start thread
+    processes[channel].thread.start()
+    return
+"""-------------------------------------------------------------------"""
+""" CHANNEL HANDLER FUNCTION """
+"""-------------------------------------------------------------------"""
+def channel_handler(channel):
+    global processes
+    loop_index = 0
+    # start looping
+    while processes[channel].stop != True:
+        # measure start time
+        start_time = time.time()
+        if processes[channel].function_type == type.pulse:
+            # calculate waiting times
+            period = 1 / processes[channel].frequency
+            high_period = period * processes[channel].duty_cycle / 100
+            low_period = period - high_period
+            # generate low cycle
+            digital.write(channel, False)
+            # wait
+            duration = time.time() - start_time
+            if duration < low_period:
+                time.sleep(low_period - duration)
+            # record starting time
+            start_time = time.time()
+            # generate high cycle
+            digital.write(channel, True)
+            # wait
+            duration = time.time() - start_time
+            if duration < high_period:
+                time.sleep(high_period - duration)
+        elif processes[channel].function_type == type.custom:
+            # generate custom signal
+            data = processes[channel].signal_data
+            digital.write(channel, data[loop_index % len(data)])
+            # wait
+            duration = time.time() - start_time
+            period = 1 / processes[channel].frequency
+            if duration < period:
+                time.sleep(period - duration)
+        else:
+            # generate random signal
+            digital.write(channel, random.choice([True, False]))
+            # wait
+            duration = time.time() - start_time
+            period = 1 / processes[channel].frequency
+            if duration < period:
+                time.sleep(period - duration)
+        # increment loop index
+        loop_index += 1
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Oscilloscope: WaveForms_HAL_Scope.py #
+<WRAP group><WRAP half column>
+This file contains functions that can command the oscilloscope to measure voltages on a specified channel or to fill a buffer with the recorded data point according to the settings with which the instrument was initialized.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" ANALOG INPUT FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import numpy
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+# triggering flag
+trigger = False
+# buffer size
+data_count = 8192
+# possible trigger options
+class trig:
+    # sources
+    class src:
+        no = (trigsrcNone, )
+        scope_ch = [(trigsrcDetectorAnalogIn, 0), (trigsrcDetectorAnalogIn, 1),
+                    (trigsrcDetectorAnalogIn, 2), (trigsrcDetectorAnalogIn, 3)]
+        digital_ch = [(trigsrcDetectorDigitalIn, 0), (trigsrcDetectorDigitalIn, 1),
+                      (trigsrcDetectorDigitalIn, 2), (trigsrcDetectorDigitalIn, 3),
+                      (trigsrcDetectorDigitalIn, 4), (trigsrcDetectorDigitalIn, 5),
+                      (trigsrcDetectorDigitalIn, 6), (trigsrcDetectorDigitalIn, 7),
+                      (trigsrcDetectorDigitalIn, 8), (trigsrcDetectorDigitalIn, 9),
+                      (trigsrcDetectorDigitalIn, 10), (trigsrcDetectorDigitalIn, 11),
+                      (trigsrcDetectorDigitalIn, 12), (trigsrcDetectorDigitalIn, 13),
+                      (trigsrcDetectorDigitalIn, 14), (trigsrcDetectorDigitalIn, 15)]
+        external_ch = [(trigsrcExternal1, ), (trigsrcExternal2, ),
+                       (trigsrcExternal3, ), (trigsrcExternal4, )]
+    # types
+    class type:
+        edge = trigtypeEdge
+        pulse = trigtypePulse
+        transition = trigtypeTransition
+    # edges
+    class edge:
+        rising = trigcondRisingPositive
+        falling = trigcondFallingNegative
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(offset=0, range=10, buffer_size=8192, frequency=20e06, trigger=False, trigger_src=trig.src.no, trigger_type=trig.type.edge, trigger_timeout=0, trigger_lvl=0, trigger_edge=trig.edge.rising):
+    global data_count
+    data_count = buffer_size
+    # enable all channels
+    dwf.FDwfAnalogInChannelEnableSet(hdwf, c_int(0), c_bool(True))
+    # set offset voltage
+    dwf.FDwfAnalogInChannelOffsetSet(hdwf, c_int(0), c_double(offset))
+    # set range
+    dwf.FDwfAnalogInChannelRangeSet(hdwf, c_int(0), c_double(range / 2))
+    # set the buffer size
+    dwf.FDwfAnalogInBufferSizeSet(hdwf, c_int(buffer_size))
+    # set the acquisition frequency
+    dwf.FDwfAnalogInFrequencySet(hdwf, c_double(frequency))
+    # disable averaging
+    dwf.FDwfAnalogInChannelFilterSet(hdwf, c_int(-1), filterDecimate)
+    # set up triggering
+    if trigger:
+        # enable/disable auto triggering
+        dwf.FDwfAnalogInTriggerAutoTimeoutSet(hdwf, c_double(trigger_timeout))
+        # set trigger source
+        dwf.FDwfAnalogInTriggerSourceSet(hdwf, trigger_src[0])
+        if trigger_src[1] != None:
+            dwf.FDwfAnalogInTriggerChannelSet(hdwf, c_int(trigger_src[1]))
+        # set trigger type
+        dwf.FDwfAnalogInTriggerTypeSet(hdwf, trigger_type)
+        # set trigger level
+        dwf.FDwfAnalogInTriggerLevelSet(hdwf, c_double(trigger_lvl))
+        # set trigger edge
+        dwf.FDwfAnalogInTriggerConditionSet(hdwf, trigger_edge)
+    return
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfAnalogInReset(hdwf)  # reset the oscilloscope
+    return
+"""-------------------------------------------------------------------"""
+""" MEASURE VOLTAGE """
+"""-------------------------------------------------------------------"""
+def measure(channel):
+    # set up the instrument
+    dwf.FDwfAnalogInConfigure(hdwf, c_bool(False), c_bool(False))
+    # read data to buffer
+    dwf.FDwfAnalogInStatus(hdwf, False, None)
+    # extract data from buffer
+    voltage = c_double()
+    dwf.FDwfAnalogInStatusSample(hdwf, c_int(channel - 1), byref(voltage))
+    return voltage.value
+"""-------------------------------------------------------------------"""
+""" RECEIVE DATA """
+"""-------------------------------------------------------------------"""
+def receive(channel):
+    # set up the instrument
+    dwf.FDwfAnalogInConfigure(hdwf, c_bool(False), c_bool(True))
+    # read data to buffer
+    while True:
+        status = c_byte()
+        dwf.FDwfAnalogInStatus(hdwf, True, byref(status))
+        if status.value == DwfStateDone.value:
+            # exit loop when ready
+            break
+    # copy buffer
+    buffer = (c_double * data_count)()
+    dwf.FDwfAnalogInStatusData(hdwf, c_int(channel - 1), buffer, data_count)
+    # convert list
+    buffer = numpy.fromiter(buffer, dtype=numpy.float)
+    buffer = buffer.tolist()
+    return buffer
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Serial Peripheral Interface (SPI) Master: WaveForms_HAL_SPI.py #
+<WRAP group><WRAP half column>
+The Analog Discovery Pro can initiate SPI communication on any of the digital pins, after which it can exchange data with the connected slave device.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" SPI FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+# endianness
+class bit_order:
+    MSB_first = 1
+    LSB_first = 0
+# pins
+class pins:
+    cs = None
+    sck = None
+    mosi = None
+    miso = None
+"""-------------------------------------------------------------------"""
+""" SPI INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(cs_pin, sck_pin, miso_pin=None, mosi_pin=None, frequency=1e06, mode=0, order=bit_order.MSB_first):
+    # save pin numbers globally
+    pins.cs = cs_pin
+    pins.sck = sck_pin
+    pins.mosi = mosi_pin
+    pins.miso = miso_pin
+    dwf.FDwfDigitalSpiFrequencySet(hdwf, c_double(
+        frequency))   # set the clock frequency
+    dwf.FDwfDigitalSpiClockSet(hdwf, c_int(sck_pin))    # set the clock pin
+    if mosi_pin != None:
+        dwf.FDwfDigitalSpiDataSet(hdwf, c_int(
+), c_int(mosi_pin))  # set the mosi pin
+        dwf.FDwfDigitalSpiIdleSet(hdwf, c_int(
+), DwfDigitalOutIdleZet)  # set the initial state
+    if miso_pin != None:
+        dwf.FDwfDigitalSpiDataSet(hdwf, c_int(
+), c_int(miso_pin))  # set the miso pin
+        dwf.FDwfDigitalSpiIdleSet(hdwf, c_int(
+), DwfDigitalOutIdleZet)  # set the initial state
+    dwf.FDwfDigitalSpiModeSet(hdwf, c_int(mode))    # set the SPI mode
+    dwf.FDwfDigitalSpiOrderSet(hdwf, c_int(order))  # set endianness
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(
+        cs_pin), c_int(1))  # set the cs pin HIGH
+    dwf.FDwfDigitalSpiWriteOne(hdwf, c_int(
+), c_int(0), c_int(0))  # dummy write
+    return
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfDigitalSpiReset(hdwf)   # reset the SPI interface
+    return
+"""-------------------------------------------------------------------"""
+""" SPI SENDING """
+"""-------------------------------------------------------------------"""
+def send(data):
+    # cast data
+    if type(data) == int:
+        data = "".join(chr(data))
+    elif type(data) == list:
+        data = "".join(chr(element) for element in data)
+    # enable the chip select line
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(pins.cs), c_int(0))
+    # create buffer to write
+    data = (c_ubyte * len(data))(*[c_ubyte(ord(character)) for character in data])
+    dwf.FDwfDigitalSpiWrite(hdwf, c_int(1), c_int(8), data, c_int(
+        len(data)))  # write array of 8 bit elements
+    # disable the chip select line
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(pins.cs), c_int(1))
+    return
+"""-------------------------------------------------------------------"""
+""" SPI RECEIVING """
+"""-------------------------------------------------------------------"""
+def receive(count):
+    # enable the chip select line
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(pins.cs), c_int(0))
+    # create buffer to store data
+    buffer = (c_ubyte*count)()
+    dwf.FDwfDigitalSpiRead(hdwf, c_int(1), c_int(8), buffer, c_int(
+        len(buffer)))  # read array of 8 bit elements
+    # disable the chip select line
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(pins.cs), c_int(1))
+    # decode data
+    data = [str(bin(element))[2:] for element in buffer]
+    data = [int(element, 2) for element in data]
+    data = "".join(chr(element) for element in data)
+    return data
+"""-------------------------------------------------------------------"""
+""" SPI EXCHANGE """
+"""-------------------------------------------------------------------"""
+def exchange(data, count):
+    # cast data
+    if type(data) == int:
+        data = "".join(chr(data))
+    elif type(data) == list:
+        data = "".join(chr(element) for element in data)
+    # enable the chip select line
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(pins.cs), c_int(0))
+    # create buffer to write
+    tx_buff = (c_ubyte * len(data)).from_buffer_copy(data)
+    # create buffer to store data
+    rx_buff = (c_ubyte*count)()
+    dwf.FDwfDigitalSpiWriteRead(hdwf, c_int(1), c_int(8), tx_buff, c_int(
+        len(tx_buff)), rx_buff, c_int(len(rx_buff)))  # write to MOSI and read from MISO
+    # decode data
+    data = [str(bin(element))[2:] for element in rx_buff]
+    data = [int(element, 2) for element in data]
+    data = "".join(chr(element) for element in data)
+    # disable the chip select line
+    dwf.FDwfDigitalSpiSelect(hdwf, c_int(pins.cs), c_int(1))
+    return data
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Static I/O: WaveForms_HAL_Static.py #
+<WRAP group><WRAP half column>
+This module can read/write the state of a digital I/O line and can set the line as input, or output.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" DIGITAL I/O FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfDigitalIOReset(hdwf)    # reset the digital I/O
+    return
+"""-------------------------------------------------------------------"""
+""" RESET PIN """
+"""-------------------------------------------------------------------"""
+def stop(pin):
+    # set pin to LOW
+    write(pin, False)
+    # disable static I/O
+    set_output(pin, False)
+    return
+"""-------------------------------------------------------------------"""
+""" READING A DIGITAL PIN """
+"""-------------------------------------------------------------------"""
+def read(pin):
+    # read a digital pin
+    # load internal buffer with current state of the pins
+    dwf.FDwfDigitalIOStatus(hdwf)
+    data = c_uint32()  # variable for this current state
+    # get the current state of the pins
+    dwf.FDwfDigitalIOInputStatus(hdwf, byref(data))
+    # convert the state to a 16 character binary string
+    data = list(bin(data.value)[2:].zfill(16))
+    # check the required bit
+    if data[15 - pin] != "0":
+        # if it is one, return True (HIGH)
+        return True
+    else:
+        # else return False (LOW)
+        return False
+"""-------------------------------------------------------------------"""
+""" SETTING A DIGITAL PIN AS OUTPUT """
+"""-------------------------------------------------------------------"""
+def set_output(pin, state=True):
+    # set a pin as output
+    # load current state of the output enable buffer
+    mask = c_uint16()
+    dwf.FDwfDigitalIOOutputEnableGet(hdwf, byref(mask))
+    # set bit mask
+    mask = set_mask(pin, mask, state)
+    # set the pin to output
+    dwf.FDwfDigitalIOOutputEnableSet(hdwf, c_int(mask))
+    return
+"""-------------------------------------------------------------------"""
+""" WRITING A DIGITAL PIN """
+"""-------------------------------------------------------------------"""
+def write(pin, state):
+    # set a pin as output
+    # load current state of the output state buffer
+    mask = c_uint16()
+    dwf.FDwfDigitalIOOutputGet(hdwf, byref(mask))
+    # set bit mask
+    mask = set_mask(pin, mask, state)
+    # set the pin state
+    dwf.FDwfDigitalIOOutputSet(hdwf, c_int(mask))
+    return
+"""-------------------------------------------------------------------"""
+""" SET MASK """
+"""-------------------------------------------------------------------"""
+def set_mask(pin, mask, value):
+    # convert to list
+    mask = list(bin(mask.value)[2:].zfill(16))
+    # set bit
+    if value:
+        mask[15 - pin] = "1"
+    else:
+        mask[15 - pin] = "0"
+    # convert to number
+    mask = "".join(element for element in mask)
+    mask = int(mask, 2)
+    return mask
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Supplies: WaveForms_HAL_Supply.py #
+<WRAP group><WRAP half column>
+This module can turn on/off the 3.3V power supply
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" POWER SUPPLY FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfAnalogIOReset(hdwf)  # reset the power supplies
+    return
+"""-------------------------------------------------------------------"""
+""" COMMANDING THE POWER SUPPLIES """
+"""-------------------------------------------------------------------"""
+def switch(state):
+    # start/stop the power supplies
+    # set the output voltage to 3.3V
+    dwf.FDwfAnalogIOChannelNodeSet(hdwf, c_int(0), c_int(0), c_double(3.3))
+    # start/stop the supplies
+    dwf.FDwfAnalogIOEnableSet(hdwf, c_int(state))
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Universal Asynchronous Receiver-Transmitter (UART) Master: WaveForms_HAL_UART.py #
+<WRAP group><WRAP half column>
+This module can be used to initialize UART communication on any of the digital I/O lines, then send/receive data on those lines.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" UART FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+# possible parity settings
+class parity:
+    none = 0
+    odd = 1
+    even = 2
+"""-------------------------------------------------------------------"""
+""" UART INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(rx_pin, tx_pin, baud_rate=9600, parity=parity.none, data_bits=8, stop_bits=1):
+    dwf.FDwfDigitalUartRateSet(hdwf, c_double(baud_rate))  # set baud rate
+    dwf.FDwfDigitalUartTxSet(hdwf, c_int(tx_pin))  # set tx pin
+    dwf.FDwfDigitalUartRxSet(hdwf, c_int(rx_pin))  # set rx pin
+    dwf.FDwfDigitalUartBitsSet(hdwf, c_int(data_bits))  # set data bit count
+    # set parity bit requirements
+    dwf.FDwfDigitalUartParitySet(hdwf, c_int(parity))
+    dwf.FDwfDigitalUartStopSet(hdwf, c_double(stop_bits))  # set stop bit count
+    # initialize tx with idle levels
+    reset_tx()
+    reset_rx()
+    return
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfDigitalUartReset(hdwf)   # reset the UART interface
+    return
+"""-------------------------------------------------------------------"""
+""" RESET RX """
+"""-------------------------------------------------------------------"""
+def reset_rx():
+    # initialize rx (dummy receive)
+    dummy_buffer = c_int(0)
+    dummy_parity_flag = c_int(0)
+    dwf.FDwfDigitalUartRx(hdwf, None, c_int(0), byref(dummy_buffer), byref(
+        dummy_parity_flag))
+    return
+"""-------------------------------------------------------------------"""
+""" RESET TX """
+"""-------------------------------------------------------------------"""
+def reset_tx():
+    # initialize tx with idle level (dummy send)
+    dwf.FDwfDigitalUartTx(hdwf, None, c_int(0))
+    return
+"""-------------------------------------------------------------------"""
+""" UART SENDING """
+"""-------------------------------------------------------------------"""
+def send(data):
+    # cast data
+    if type(data) == int:
+        data = "".join(chr(data))
+    elif type(data) == list:
+        data = "".join(chr(element) for element in data)
+    # encode the string into a string buffer
+    data = create_string_buffer(data.encode("UTF-8"))
+    # send text, trim zero ending
+    dwf.FDwfDigitalUartTx(hdwf, data, c_int(sizeof(data)-1))
+    return
+"""-------------------------------------------------------------------"""
+""" UART RECEIVING """
+"""-------------------------------------------------------------------"""
+def receive(chunk="", error="no error"):
+    data = create_string_buffer(8193)   # create empty string buffer
+    count = c_int(0)    # character counter
+    parity_flag = c_int(0)    # parity check result
+    dwf.FDwfDigitalUartRx(hdwf, data, c_int(
+        sizeof(data)-1), byref(count), byref(parity_flag))  # read up to 8k characters
+    if count.value > 0:
+        data[count.value] = 0  # add zero ending
+        # make a string from the string buffer
+        data = list(data.value)
+        data = "".join(chr(element) for element in data)
+        # attach previous data
+        data = chunk + data
+        # decode parity check results
+        if parity_flag.value == 0 and error == "no error":
+            parity_flag = "no error"
+        elif parity_flag.value < 0:
+            parity_flag = "buffer overflow"
+        elif parity_flag.value > 0:
+            parity_flag = "parity error: {}".format(parity_flag.value)
+        else:
+            parity_flag = error
+        # propagate previous results
+        data, parity_flag = receive(chunk=data, error=parity_flag)
+    else:
+        data = chunk
+        parity_flag = error
+    return data, parity_flag
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Waveform Generator: WaveForms_HAL_Wavegen.py #
+<WRAP group><WRAP half column>
+This module can be used to generate analog signals with the required parameters. Possible functions are also present in the module as class members.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Analog Discovery Pro using the WaveForms SDK"""
+""" ANALOG OUTPUT FUNCTIONS """
+# import necessary modules
+from ctypes import *
+from WaveForms_HAL.dwfconstants import *
+import sys
+if sys.platform.startswith("win"):
+    dwf = cdll.dwf
+elif sys.platform.startswith("darwin"):
+    dwf = cdll.LoadLibrary("/Library/Frameworks/dwf.framework/dwf")
+else:
+    dwf = cdll.LoadLibrary("libdwf.so")
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+# global variables
+hdwf = c_int()  # device handle
+# function types
+class type:
+    custom = funcCustom
+    sine = funcSine
+    square = funcSquare
+    triangle = funcTriangle
+    noise = funcNoise
+    dc = funcDC
+    pulse = funcPulse
+    trapezium = funcTrapezium
+    sine_power = funcSinePower
+    class ramp:
+        up = funcRampUp
+        down = funcRampDown
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # reset the instrument
+    dwf.FDwfAnalogOutReset(hdwf)  # reset the waveform generator
+    return
+"""-------------------------------------------------------------------"""
+""" GENERATION """
+"""-------------------------------------------------------------------"""
+def generate(channel, function, amplitude, frequency=1e03, symmetry=50, offset=0, data=None, run_time=0, wait_time=0, repeat_time=0):
+    # enable channel
+    channel -= 1
+    dwf.FDwfAnalogOutNodeEnableSet(
+        hdwf, channel, AnalogOutNodeCarrier, c_bool(True))
+    # set function type
+    dwf.FDwfAnalogOutNodeFunctionSet(
+        hdwf, channel, AnalogOutNodeCarrier, function)
+    if function == type.custom:
+        dwf.FDwfAnalogOutNodeDataSet(
+            hdwf, channel, AnalogOutNodeCarrier, data, len(data))
+    # set frequency
+    dwf.FDwfAnalogOutNodeFrequencySet(
+        hdwf, channel, AnalogOutNodeCarrier, c_double(frequency))
+    # set amplitude
+    dwf.FDwfAnalogOutNodeAmplitudeSet(
+        hdwf, channel, AnalogOutNodeCarrier, c_double(amplitude))
+    # set offset
+    if function == type.dc:
+        dwf.FDwfAnalogOutNodeOffsetSet(
+            hdwf, channel, AnalogOutNodeCarrier, c_double(amplitude))
+    else:
+        dwf.FDwfAnalogOutNodeOffsetSet(
+            hdwf, channel, AnalogOutNodeCarrier, c_double(offset))
+    # set symmetry
+    dwf.FDwfAnalogOutNodeSymmetrySet(
+        hdwf, channel, AnalogOutNodeCarrier, c_double(symmetry))
+    # set running time limit
+    dwf.FDwfAnalogOutRunSet(hdwf, channel, c_double(run_time))
+    # set wait time before start
+    dwf.FDwfAnalogOutWaitSet(hdwf, channel, c_double(wait_time))
+    # set number of repeating cycles
+    dwf.FDwfAnalogOutRepeatSet(hdwf, channel, c_int(repeat_time))
+    # start
+    dwf.FDwfAnalogOutConfigure(hdwf, channel, c_bool(True))
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+</WRAP>
+----
+===== Creating a Library for the Pmods =====
+<WRAP group>
+Now a library should be created to control the Pmods easily. These Pmod drivers will be created in a similar way to the HAL, but will use it to control the hardware. If you are not interested in the details of this module, skip to the next section. The library containing the modules can be downloaded {{ :test-and-measurement:analog-discovery-pro-3x50:pmod.zip |here}}.
+</WRAP>
+<WRAP center round important 60%>
+In the attached package, not all the functions were tested, so errors might appear in some cases. Use the package on your own responsibility and feel free to modify it.
+</WRAP>
+<WRAP group>
+Create a new folder and inside create an initializer file and separate files for every Pmod you want to use.
+--> Wrapper: __init__.py #
+<WRAP group><WRAP half column>
+This module imports all submodules and names them
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with multiple PMODs """
+""" WRAPPER """
+from PMOD import PMOD_ALS as ALS
+from PMOD import PMOD_BLE as BLE
+from PMOD import PMOD_DA1 as DA1
+from PMOD import PMOD_KYPD as KYPD
+from PMOD import PMOD_OD1 as OD1
+</code>
+</WRAP></WRAP>
+<--
+--> Pmod ALS: PMOD_ALS.py #
+<WRAP group><WRAP half column>
+The ambient light sensor uses the SPI interface for communication, with three lines (chip select, serial data out and serial clock) and a clock frequency between 1MHz and 4MHz. The on-board analog to digital converter returns 2 bytes of data, most significant bit first, which contain 3 leading and 4 trailing zeros. The sensor saturates at the output value 127. The module also converts the raw data into percentage.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Pmod ALS """
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+class pins:
+    cs = 0  # CS pin of the Pmod
+    sdo = 1  # SDO pin of the Pmod
+    sck = 2  # SCK pin of the Pmod
+# WaveForms SDK HAL object
+WF = None
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(WaveForms_HAL):
+    global WF
+    WF = WaveForms_HAL
+    # start the power supply
+    WF.supply.switch(True)
+    # initialize the SPI interface
+    WF.spi.initialize(cs_pin=pins.cs, sck_pin=pins.sck,
+                      miso_pin=pins.sdo, frequency=1e06)
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    pass
+    return
+"""-------------------------------------------------------------------"""
+""" RECEIVE DATA """
+"""-------------------------------------------------------------------"""
+def receive_data():
+    data = WF.spi.receive(2)   # read 2 bytes
+    msb = ord(data[0]) & 0xFF
+    lsb = ord(data[1]) & 0xFF
+    # concatenate bytes without trailing and leading zeros
+    result = ((msb << 3) | (lsb >> 4)) & 0xFF
+    return result
+"""-------------------------------------------------------------------"""
+""" RECEIVE PERCENTAGE """
+"""-------------------------------------------------------------------"""
+def receive_percent():
+    # receive and convert raw data
+    data = receive_data() * 100 / 127
+    return round(data, 2)
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Pmod BLE: PMOD_BLE.py #
+<WRAP group><WRAP half column>
+The Pmod BLE is a Bluetooth Low Energy module, which communicates on UART interface, using a 115200bps baud rate. The controlling module contains functions to factory reset the device by putting it into command mode and sending the necessary commands. Besides that, it also can send and receive data, decoding the received bytes and separating the buffer into a list which contains only data and one which contains only system messages (starting and ending with "%").
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Pmod BLE """
+import time
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+class pins:
+    rx = 0  # TX pin of the Pmod
+    tx = 1  # RX pin of the Pmod
+    rst = 2  # RESET pin of the Pmod
+class commands:
+    command_mode = "$$$"    # enter command mode
+    data_mode = "---\r"  # enter data mode
+    rename = "S-,PmodBLE\r"  # set name to PmodBLE_XXXX
+    factory_reset = "SF,1\r"    # factory reset
+    high_power = "SGA,0\r"  # set high power output
+    code = "SP,123456\r"    # set pin code to "123456"
+    mode = "SS,C0\r"    # support device info + UART Transparent
+    reboot = "R,1\r"    # reboots the device
+# WaveForms SDK HAL object
+WF = None
+# variables for detecting system messages
+currently_sys = False
+previous_msg = ""
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(WaveForms_HAL, first_run=False):
+    global WF
+    WF = WaveForms_HAL
+    # start the power supply
+    WF.supply.switch(True)
+    # initialize the UART interface
+    WF.uart.initialize(rx_pin=pins.tx, tx_pin=pins.rx, baud_rate=115200)
+    # factory reset the Pmod
+    if first_run:
+        reset()
+    return
+"""-------------------------------------------------------------------"""
+""" REBOOT """
+"""-------------------------------------------------------------------"""
+def reboot():
+    # hard reset the device
+    # pull down the reset line
+    WF.digital.write(pins.rst, False)
+    # wait
+    time.sleep(1)
+    # pull up the reset line
+    WF.digital.write(pins.rst, True)
+    return
+"""-------------------------------------------------------------------"""
+""" RESET """
+"""-------------------------------------------------------------------"""
+def reset():
+    # enter command mode
+    send_command(commands.command_mode)
+    time.sleep(3)
+    # factory reset the Pmod
+    success = send_command(commands.factory_reset)
+    while success != True:
+        success = send_command(commands.factory_reset)
+        time.sleep(1)
+    # enter command mode
+    send_command(commands.command_mode)
+    time.sleep(3)
+    # rename device
+    send_command(commands.rename)
+    time.sleep(1)
+    # set high power mode
+    send_command(commands.high_power)
+    time.sleep(1)
+    # set communication mode
+    send_command(commands.mode)
+    time.sleep(1)
+    # exit command mode
+    send_command(commands.data_mode)
+    time.sleep(3)
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    # restart the module
+    reboot()
+    return
+"""-------------------------------------------------------------------"""
+""" SEND COMMAND """
+"""-------------------------------------------------------------------"""
+def send_command(command):
+    # send the command
+    send_data(command)
+    # record response
+    response, _, error = receive_data
+    # analyze response
+    response = response[0:3]
+    if response == "ERR" or response == "Err" or error != "no error":
+        return False
+    return True
+"""-------------------------------------------------------------------"""
+""" SEND DATA """
+"""-------------------------------------------------------------------"""
+def send_data(data):
+    # send data
+    WF.uart.send(data)
+    return
+"""-------------------------------------------------------------------"""
+""" RECEIVE DATA """
+"""-------------------------------------------------------------------"""
+def receive_data():
+    global previous_msg, currently_sys
+    # record incoming message
+    data, error = WF.uart.receive()
+    sys_msg = ""
+    # check for system messages
+    special = data.count("%")
+    """---------------------------------"""
+    if special == 0:
+        if currently_sys:
+            # the middle of a system message
+            previous_msg = previous_msg + data
+            data = ""
+        else:
+            # not a system message
+            pass
+        """---------------------------------"""
+    elif special == 2:
+        # clear system message
+        sys_msg = data
+        data = ""
+        currently_sys = False
+        previous_msg = ""
+        """---------------------------------"""
+    else:
+        # fragmented system message
+        data_list = data.split("%")
+        if currently_sys:
+            # the end of the message
+            sys_msg = previous_msg + data_list[0] + "%"
+            currently_sys = False
+            previous_msg = ""
+            data = data_list[1]
+        else:
+            # the start of the message
+            currently_sys = True
+            previous_msg = "%" + data_list[1]
+            data = data_list[0]
+    return data, sys_msg, error
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Pmod DA1: PMOD_DA1.py #
+<WRAP group><WRAP half column>
+The digital to analog converter also communicates via the SPI interface. The Pmod DA1 includes two DAC chips that have common chip select and serial clock pins. Both chips contain two 8-bit DAC channels, so in total, the Pmod features four different conversion channels. The program computes the 8-bit data word from the voltage, then appends it to the command word specific to the DAC channel. To use chip 1, or chip 2, the command and data words must be sent on the data 0, or data 1 lines.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Pmod DA1 """
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+class pins:
+    sync = 0  # CS pin of the Pmod
+    d0 = 1  # data 0 pin of the Pmod
+    d1 = 2  # data 0 pin of the Pmod
+    sck = 3  # SCK pin of the Pmod
+class output_channel:
+    # channels of the digital to analog converter
+    A1 = 0
+    B1 = 1
+    A2 = 2
+    B2 = 3
+# voltage limits in Volts
+max_voltage = 3.3
+min_voltage = 0
+# WaveForms SDK HAL object
+WF = None
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(WaveForms_HAL):
+    global WF
+    WF = WaveForms_HAL
+    # start the power supply
+    WF.supply.switch(True)
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    pass
+    return
+"""-------------------------------------------------------------------"""
+""" SEND VOLTAGE """
+"""-------------------------------------------------------------------"""
+def output_voltage(channel, voltage):
+    # select DAC chip
+    mosi = pins.d0
+    if channel == output_channel.A2 or channel == output_channel.B2:
+        mosi = pins.d1
+    # initialize the SPI interface
+    WF.spi.initialize(cs_pin=pins.sync, sck_pin=pins.sck,
+                      mosi_pin=mosi, frequency=1e06)
+    # limit and encode voltage
+    voltage = max(min(voltage, max_voltage), min_voltage)
+    data = round(voltage * 255 / 3.3) & 0xFF
+    # select channel
+    command = 3
+    if channel == output_channel.B1 or channel == output_channel.B2:
+        command = 7
+    # send both words
+    WF.spi.send([command, data])
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Pmod KYPD: PMOD_KYPD.py #
+<WRAP group><WRAP half column>
+This module uses the static I/O instrument to read the current state of the keypad and returns the pressed keys.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Pmod KYPD """
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+class pins:
+    rows = [7, 6, 5, 4]    # pins connected to keypad rows
+    columns = [3, 2, 1, 0]  # pins connected to keypad columns
+# the layout of the keypad
+keymap = [["1", "2", "3", "A"],
+          ["4", "5", "6", "B"],
+          ["7", "8", "9", "C"],
+          ["0", "F", "E", "D"]]
+# WaveForms SDK HAL object
+WF = None
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(WaveForms_HAL):
+    global WF
+    WF = WaveForms_HAL
+    # enable the power supply
+    WF.supply.switch(True)
+    # for every pin connected to a row
+    for pin in pins.rows:
+        WF.digital.set_output(pin)  # set the pin as output
+        WF.digital.write(pin, False)    # set a starting state of LOW
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    pass
+    return
+"""-------------------------------------------------------------------"""
+""" GETTING THE KEYPAD STATE """
+"""-------------------------------------------------------------------"""
+def receive_data():
+    # get the current state of the Pmod KYPD
+    result = []  # buffer to store the results
+    # go through all the rows
+    for index_1 in range(len(pins.rows)):
+        # set the state of every row
+        for index_2 in range(len(pins.rows)):
+            # only one row is HIGH at every moment
+            if index_1 == index_2:
+                # set the current row HIGH
+                WF.digital.write(pins.rows[index_2], True)
+            else:
+                # set the current row LOW
+                WF.digital.write(pins.rows[index_2], False)
+        # check every column
+        for index_2 in range(len(pins.columns)):
+            # if the current column is HIGH
+            if WF.digital.read(pins.columns[index_2]):
+                # append the respective key to the results
+                result.append(keymap[index_1][index_2])
+    # return the results
+    return result
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+--> Pmod OD1: PMOD_OD1.py #
+<WRAP group><WRAP half column>
+The Pmod OD1 contains four open drain MOSFETs, which act like switches: if a gate pin is set HIGH (True), the respective MOSFET grounds the connected line. If the gate pin is set to LOW (False), the MOSFET input (the drain) has high impedance. The module realizes functions for turning the switches on/off, toggling and driving them with a pulse width modulated (PWM) signal. When driving the MOSFETs with the PWM signal, the type of signal generation (static, or pattern generator) can be defined as a parameter.
+</WRAP><WRAP half column>
+<code python>
+""" This module realizes communication with the Pmod ALS """
+"""-------------------------------------------------------------------"""
+""" VARIABLES """
+"""-------------------------------------------------------------------"""
+class pins:
+    g1 = 0  # G1 pin of the Pmod
+    g2 = 1  # G2 pin of the Pmod
+    g3 = 2  # G3 pin of the Pmod
+    g4 = 3  # G4 pin of the Pmod
+# WaveForms SDK HAL object
+WF = None
+"""-------------------------------------------------------------------"""
+""" INITIALIZATION """
+"""-------------------------------------------------------------------"""
+def initialize(WaveForms_HAL):
+    global WF
+    WF = WaveForms_HAL
+    # start the power supply
+    WF.supply.switch(True)
+    return
+"""-------------------------------------------------------------------"""
+""" CLEANUP """
+"""-------------------------------------------------------------------"""
+def close():
+    WF.static_pattern.reset()
+    return
+"""-------------------------------------------------------------------"""
+""" SWITCH ON """
+"""-------------------------------------------------------------------"""
+def on(channel):
+    pin = None
+    if channel == 1:
+        pin = pins.g1
+    elif channel == 2:
+        pin = pins.g2
+    elif channel == 3:
+        pin = pins.g3
+    elif channel == 4:
+        pin = pins.g4
+    if pin != None:
+        # initialize the pins
+        WF.static_pattern.stop(pin)
+        WF.digital.set_output(pin)
+        # switch on MOSFET
+        WF.digital.write(pin, True)
+    return
+"""-------------------------------------------------------------------"""
+""" SWITCH OFF """
+"""-------------------------------------------------------------------"""
+def off(channel):
+    pin = None
+    if channel == 1:
+        pin = pins.g1
+    elif channel == 2:
+        pin = pins.g2
+    elif channel == 3:
+        pin = pins.g3
+    elif channel == 4:
+        pin = pins.g4
+    if pin != None:
+        # initialize the pins
+        WF.static_pattern.stop(pin)
+        WF.digital.set_output(pin)
+        # switch off MOSFET 4
+        WF.digital.write(pin, False)
+    return
+"""-------------------------------------------------------------------"""
+""" SWITCH """
+"""-------------------------------------------------------------------"""
+def switch(channel):
+    pin = None
+    if channel == 1:
+        pin = pins.g1
+    elif channel == 2:
+        pin = pins.g2
+    elif channel == 3:
+        pin = pins.g3
+    elif channel == 4:
+        pin = pins.g4
+    if pin != None:
+        # initialize the pins
+        WF.static_pattern.stop(pin)
+        WF.digital.set_output(pin)
+        # switch off MOSFET 4
+        state = WF.digital.read(pin)
+        WF.digital.write(pin, not state)
+    return
+"""-------------------------------------------------------------------"""
+""" DRIVE MOSFET WITH PWM SIGNAL """
+"""-------------------------------------------------------------------"""
+def drive(channel, frequency, duty_cycle, static=False):
+    # enable/disable running in the background
+    instrument = WF.pattern
+    if static:
+        instrument = WF.static_pattern
+    if channel == 1:
+        # drive MOSFET 1
+        instrument.generate(pins.g1, frequency,
+                            instrument.type.pulse, duty_cycle=duty_cycle)
+    elif channel == 2:
+        # drive MOSFET 2
+        instrument.generate(pins.g2, frequency,
+                            instrument.type.pulse, duty_cycle=duty_cycle)
+    elif channel == 3:
+        # drive MOSFET 3
+        instrument.generate(pins.g3, frequency,
+                            instrument.type.pulse, duty_cycle=duty_cycle)
+    elif channel == 4:
+        # drive MOSFET 4
+        instrument.generate(pins.g4, frequency,
+                            instrument.type.pulse, duty_cycle=duty_cycle)
+    return
+"""-------------------------------------------------------------------"""
+</code>
+</WRAP></WRAP>
+<--
+</WRAP>
+----
+===== Testing the Modules =====
+<WRAP group>
+To make sure that the previously created Python modules work (and to provide examples for later usage), they should be tested. If you are not interested in the details of this testing, skip to the next section. The test scripts can be downloaded {{ :test-and-measurement:analog-discovery-pro-3x50:tests.zip |here}}.
+</WRAP>
+<WRAP group>
+Create test files for all Pmods and the Analog and Digital input-output instruments in the same folder, where the //WaveForms_HAL// and //PMOD// folders are.
+--> Testing the Oscilloscope and the Waveform Generator: Test_HAL_Analog.py #
+<WRAP group><WRAP half column>
+To test the functionality of the analog input-output modules, first connect an oscilloscope channel to one of the waveform generator's channels, then output a DC voltage on the waveform generator and measure it with the scope. An AC signal should also be outputted and read back with the scope, then plotted using the matplotlib module.
+{{ :test-and-measurement:analog-discovery-pro-3x50:analog_test.png?400 |}}
+</WRAP><WRAP half column>
+<code python>
+# import modules
+import WaveForms_HAL as WF
+import matplotlib.pyplot as plt
+# define used channels
+scope_ch = 1
+wavegen_ch = 1
+# define signal parameters
+dc_voltage = 2.25
+sin_amplitude = 2.0
+sin_frequency = 50e03
+try:
+    # initialize the interface
+    WF.initialize()
+    # initialize the scope with default settings
+    WF.scope.initialize()
+    # output a DC voltage
+    WF.wavegen.generate(wavegen_ch, WF.wavegen.type.dc, dc_voltage)
+    # display measured voltage level
+    print(WF.scope.measure(scope_ch))
+    # output a sine signal
+    WF.wavegen.generate(wavegen_ch, WF.wavegen.type.sine,
+                        amplitude=sin_amplitude, frequency=sin_frequency)
+    while True:
+        plt.plot(WF.scope.receive(scope_ch))    # plot recorded signal
+        plt.show()
+except KeyboardInterrupt:
+    pass
+finally:
+    # close device
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+--> Testing the Logic Analyzer and the Pattern Generator: Test_HAL_Digital.py #
+<WRAP group><WRAP half column>
+To test the functionality of the digital input-output modules, a PWM signal is generated on one of the digital input-output channels. The signal is read back on the same pin, then plotted using the matplotlib module.
+{{ :test-and-measurement:analog-discovery-pro-3x50:digital_test.png?400 |}}
+</WRAP><WRAP half column>
+<code python>
+# import modules
+import WaveForms_HAL as WF
+import matplotlib.pyplot as plt
+# define used digital pin
+pin = 1
+# define signal parameters
+frequency = 50e03
+duty_cycle = 30
+try:
+    # initialize the interface
+    WF.initialize()
+    # initialize the logic analyzer with default settings
+    WF.logic.initialize()
+    # generate a signal
+    WF.pattern.generate(
+        pin, frequency, WF.pattern.type.pulse, duty_cycle=duty_cycle)
+    while True:
+        plt.plot(WF.logic.receive_data(pin))    # plot recorded signal
+        plt.show()
+except KeyboardInterrupt:
+    pass
+finally:
+    # close the device
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+--> Testing the Pmod ALS: Test_PMOD_ALS.py #
+<WRAP group><WRAP half column>
+To test the Pmod ALS, the ambient light intensity is read and displayed continuously.
+</WRAP><WRAP half column>
+<code python>
+# import modules
+from PMOD import ALS
+import WaveForms_HAL as WF
+# define pins
+ALS.pins.cs = 10
+ALS.pins.sdo = 9
+ALS.pins.sck = 8
+try:
+    # initialize the interface
+    WF.initialize()
+    ALS.initialize(WF)
+    while True:
+        # display measurements
+        print(ALS.receive_percent())
+except KeyboardInterrupt:
+    pass
+finally:
+    # close the device
+    ALS.close()
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+--> Testing the Pmod BLE: Test_PMOD_BLE.py #
+<WRAP group><WRAP half column>
+To test the Pmod BLE, all messages received on Bluetooth are displayed, the string "got it" is sent as a response.
+To be able to test the Pmod, download the [[https://play.google.com/store/apps/details?id=com.macdom.ble.blescanner|BLE Scanner]] application to your phone. Run the Python script, then start the application. It will ask you to turn on Bluetooth and location. After some time, you should see the Pmod BLE appearing in the scanner.
+{{ :test-and-measurement:analog-discovery-pro-3x50:ble_test_device.jpeg?200 |}}
+<WRAP center round important 90%>
+Note the long code (MAC address) below the name of the device. It will be important later.
+</WRAP>
+Connect to it, then open **Custom Service** and tap the **N** (notify) icon in the first custom characteristic. You should see system messages appearing in the output stream of the Python script. Also, the "got it" message should appear at the custom characteristic. To send data, tap the **W** icon and type in your message.
+{{ :test-and-measurement:analog-discovery-pro-3x50:ble_test_services.jpeg?200 |}}
+<WRAP center round important 90%>
+Note the long code (UUID) of the service and the characteristic you are using. It will be important later.
+</WRAP>
+</WRAP><WRAP half column>
+<code python>
+# import modules
+from PMOD import BLE
+import WaveForms_HAL as WF
+# define pins
+BLE.pins.tx = 6
+BLE.pins.rx = 5
+BLE.pins.rst = 4
+try:
+    # initialize the interface
+    WF.initialize()
+    BLE.initialize(WF)
+    BLE.reboot()
+    while True:
+        # receive data
+        data, sys_msg, error = BLE.receive_data()
+        # merge data and system messages
+        buf = ""
+        if len(data) > 0:
+            buf = data
+        elif len(sys_msg) > 0:
+            buf = sys_msg
+        # if the data is valid
+        if len(buf) > 0:
+            print(buf)  # display it
+            BLE.send_data(" got it")  # and send response
+        # if the data isn't valid
+        elif error != "no error":
+            print(error)    # display the error
+except KeyboardInterrupt:
+    pass
+finally:
+    # close the device
+    BLE.reboot()
+    BLE.close()
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+--> Testing the Pmod DA1: Test_PMOD_DA1.py #
+<WRAP group><WRAP half column>
+Connect the oscilloscope channels of the ADP to the output channels of the Pmod DA1, then run the script. Enter voltage levels for each DAC channel, then compare them with the ones measured by the oscilloscope. Enter an "x" to finish the program.
+</WRAP><WRAP half column>
+<code python>
+# import modules
+from PMOD import DA1
+import WaveForms_HAL as WF
+# define used pins
+DA1.pins.sync = 3
+DA1.pins.d0 = 2
+DA1.pins.d1 = 1
+DA1.pins.sck = 0
+try:
+    # initialize the interface
+    WF.initialize()
+    DA1.initialize(WF)
+    # initialize the scope with default settings
+    WF.scope.initialize()
+    while True:
+        # read voltage from keyboard
+        voltage = input("Set voltage for A1: ")
+        # check exit condition
+        if voltage == "x":
+            break
+        # set voltage
+        DA1.output_voltage(DA1.output_channel.A1, float(voltage))
+        # display measured voltage levels
+        print([WF.scope.measure(1), WF.scope.measure(2), WF.scope.measure(3), WF.scope.measure(4)])
+        # read voltage from keyboard
+        voltage = input("Set voltage for B1: ")
+        # check exit condition
+        if voltage == "x":
+            break
+        # set voltage
+        DA1.output_voltage(DA1.output_channel.B1, float(voltage))
+        # display measured voltage levels
+        print([WF.scope.measure(1), WF.scope.measure(2), WF.scope.measure(3), WF.scope.measure(4)])
+        # read voltage from keyboard
+        voltage = input("Set voltage for A2: ")
+        # check exit condition
+        if voltage == "x":
+            break
+        # set voltage
+        DA1.output_voltage(DA1.output_channel.A2, float(voltage))
+        # display measured voltage levels
+        print([WF.scope.measure(1), WF.scope.measure(2), WF.scope.measure(3), WF.scope.measure(4)])
+        # read voltage from keyboard
+        voltage = input("Set voltage for B2: ")
+        # check exit condition
+        if voltage == "x":
+            break
+        # set voltage
+        DA1.output_voltage(DA1.output_channel.B2, float(voltage))
+        # display measured voltage levels
+        print([WF.scope.measure(1), WF.scope.measure(2), WF.scope.measure(3), WF.scope.measure(4)])
+except KeyboardInterrupt:
+    pass
+finally:
+    # close the device
+    DA1.close()
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+--> Testing the Pmod KYPD: Test_PMOD_KYPD.py #
+<WRAP group><WRAP half column>
+To test the keypad, read and display the pressed keys continuously.
+</WRAP><WRAP half column>
+<code python>
+# import modules
+from PMOD import KYPD
+import WaveForms_HAL as WF
+# define pins
+KYPD.pins.rows = [7, 6, 5, 4]
+KYPD.pins.columns = [3, 2, 1, 0]
+try:
+    # initialize the interface
+    WF.initialize()
+    KYPD.initialize(WF)
+    while True:
+        # display pressed keys
+        print(KYPD.receive_data())
+except KeyboardInterrupt:
+    pass
+finally:
+    # close the device
+    KYPD.close()
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+--> Testing the Pmod OD1: Test_PMOD_OD1.py #
+<WRAP group><WRAP half column>
+To test the open drain MOSFETs, connect the cathode (shorter lead) of some LEDs to the MOSFET drains. Connect one and of 470Ω resistors to the anodes (longer lead) of the LEDs. Connect the other lead of the resistors to the power supply output (red cable) on ADP.
+The script turns on and off every LED one after the other, then repeats this step, but with the toggling function. When finished, enter duty cycles for every PWM signal commanding the MOSFETs to set the brightness of the LEDs. Finish the script by entering "x" instead of a duty cycle.
+</WRAP><WRAP half column>
+<code python>
+# import modules
+from PMOD import OD1
+import WaveForms_HAL as WF
+import time
+# define used pins
+OD1.pins.g1 = 3
+OD1.pins.g2 = 2
+OD1.pins.g3 = 1
+OD1.pins.g4 = 0
+# define signal frequency
+frequency = 1
+# define PWM type
+static_pwm = True
+# require static testing
+static_required = False
+# define delay after operations
+delay = 1   # in seconds
+try:
+    # initialize the interface
+    WF.initialize()
+    OD1.initialize(WF)
+    if static_required:
+        # try the on/off functions
+        for index in range(1, 5):
+            OD1.on(index)   # turn on MOSFET
+            print("on")  # display message
+            time.sleep(delay)   # wait
+            OD1.off(index)  # turn off MOSFET
+            print("off")  # display message
+            time.sleep(delay)   # wait
+        # try the toggling function
+        for index in range(1, 5):
+            OD1.switch(index)   # toggle MOSFET
+            print("toggle")  # display message
+            time.sleep(delay)   # wait
+            OD1.switch(index)   # toggle MOSFET
+            print("toggle")  # display message
+            time.sleep(delay)   # wait
+    while True:
+        # read duty cycles from keyboard
+        duty = input("First MOSFET duty cycle: ")
+        # check exit condition
+        if duty == "x":
+            break
+        # test the pwm drive functions
+        OD1.drive(1, frequency, int(duty), static=static_pwm)
+        duty = input("Second MOSFET duty cycle: ")
+        if duty == "x":
+            break
+        OD1.drive(2, frequency, int(duty), static=static_pwm)
+        duty = input("Third MOSFET duty cycle: ")
+        if duty == "x":
+            break
+        OD1.drive(3, frequency, int(duty), static=static_pwm)
+        duty = input("Fourth MOSFET duty cycle: ")
+        if duty == "x":
+            break
+        OD1.drive(4, frequency, int(duty), static=static_pwm)
+except KeyboardInterrupt:
+    pass
+finally:
+    # turn off everything
+    OD1.off(1)
+    OD1.off(2)
+    OD1.off(3)
+    OD1.off(4)
+    # close the device
+    OD1.close()
+    WF.close()
+</code>
+</WRAP></WRAP>
+<--
+</WRAP>
+----
+===== Building the Application =====
+<WRAP group>
+<WRAP group><WRAP half column>
+To build an Android application, the [[https://appinventor.mit.edu/|MIT App Inventor]] web application will be used. Open the site, create a new user, then start a new project. First, create the user interface of the application by drag and dropping user interface elements onto the virtual phone. Use the companion app on your real phone to see how the user interface will look. Alternatively, you can download and import the already created {{ :test-and-measurement:analog-discovery-pro-3x50:smart_lamp_project.zip |project file}}, or just download and install on your phone the final {{ :test-and-measurement:analog-discovery-pro-3x50:smart_lamp_app.zip |application}}.
+For this application, a switch, three sliders, and several labels are needed. Use the //Horizontal Arrangement// and //Vertical Arrangement// blocks from the //Layout// menu to arrange everything on the screen.
+When you are ready, find the //Extension// menu and import the [[https://appinventor2.droidim.com/mdocs-posts/bluetooth-low-energy-by-mit|Bluetooth Low Energy by MIT]] extension. Drag and drop a BLE component on the screen of the virtual phone.
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:app_builder_front.png?600 |}}
+</WRAP></WRAP>
+<WRAP group><WRAP half column>
+When you are finished with the user interface, enter Block view. Here use the puzzle pieces to create the logic backbone of your application. Define what happens when the user touches a slider/switch/label, when the Bluetooth module connects/disconnects/receives a message. Define what data do you want to send and how to decode the received information. If you have never created an application before, this is a great way to start.
+<WRAP center round tip>
+Use comments on the pieces (small blue circles with a question mark) to make your "code" easy to understand.
+</WRAP>
+<WRAP center round tip>
+In this editor, every separate puzzle piece runs as an interrupt. Use this to your advantage.
+</WRAP>
+<WRAP center round tip>
+Hiding a component and invisible components can be useful. You can use an invisible error message, which is made visible only if an error appears, then hide it again using a timer interrupt, to display connection problems - this can be extremely useful during debugging.
+</WRAP>
+<WRAP center round tip>
+To easily access the BLE device, service and characteristic you need, use the **MAC address**, **Service UUID** and **Characteristic UUID** obtained previously. If you don't have those, you can find the addresses by following this step: [[test-and-measurement:analog-discovery-pro-3x50:smart-lamp#testing_the_modules|Testing the Pmod BLE]].
+</WRAP>
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:app_builder_back.png?600 |}}
+</WRAP></WRAP>
+<WRAP group>
+When you are ready, build the application and install it on your phone. To install it, you must enable installation from unknown sources. After installing the app, you might encounter warning messages from Google Play Protect, but just ignore them.
+</WRAP>
+</WRAP>
+----
+===== Hardware Setup =====
+<WRAP group>
+=== Connecting the PMODs ===
+<WRAP group><WRAP half column>
+Connect the Pmod ALS, the Pmod BLE, the Pmod DA1, and one channel of the Pmod OD1 to the Analog Discovery Pro.
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:adp_pmods_bb.png?600 |}}
+</WRAP></WRAP>
+=== Building the PWM Generator ===
+<WRAP group><WRAP half column>
+Connect three output channels of the Pmod DA1 to the inverting input of the comparators realized with the OP484 operational amplifier. To the non-inverting input, connect the second channel of the waveform generator. This circuit will create the PWM signals from the numerical data: the waveform generator outputs a sawtooth signal with 0.5V amplitude and 0.5V offset and this signal is compared to the voltage levels provided by the DAC so the rail-to-rail comparator generates logic levels according to the comparison result. The duty cycle of the resulting signal can be easily set: 0V on the DAC means 100% duty cycle, while 1V on the DAC means 0% duty cycle.
+Connect the outputs of the comparators to the remaining MOSFET gates on the Pmod OD1.
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:pwm_generator_bb.png?600 |}}
+</WRAP></WRAP>
+<WRAP group><WRAP half column>
+To test the PWM generator circuit, you can connect an oscilloscope channel to the output of a comparator, then use WaveForms to generate the signal: first provide power to the Pmods by enabling the Supplies instrument, then generate the reference signal (sawtooth signal with 500mV offset and 500mV amplitude) on the second Wavegen channel. Use the SPI Master tool in the Protocol instrument to command the DAC and the Scope to display the generated signal. To generate the control voltages, use the command 0x03 to select channel A, or 0x07 to select channel B (the data line selects the DAC chip), then send the data word (a number between 0 - 0V and 77 - 0.99V). The duty cycle is set by the sent data word.
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:pwm_generator_test.png?600 |}}
+</WRAP></WRAP>
+=== Building the Charger Circuit ===
+<WRAP group><WRAP half column>
+Use the Micro-USB plug to provide power to the battery charger. You can connect the charger to the back panel of the ADP. The charger consists of a programmable current sink, realized with the LT3092. The reference voltage will be provided by the first waveform generator channel of the ADP. The current sink can charge up the Li-Po cell until it reaches 4.2V. From here the cell would need a constant voltage source with decreasing current to get the topping charge, but to keep the circuit simple, this part won't be implemented.
+To prevent the negative lead of the battery from becoming floating, the first MOSFET is used in the Pmod OD1 to couple it to the ground, when the charger isn't plugged in. A charge signaling LED is also connected to the ADP to provide feedback.
+To be able to measure the voltage of the battery cell, connect the first oscilloscope channel to the negative lead of the battery and the second channel to the positive lead. As the scope channels have a common reference, the difference between the two measurements will give the battery voltage.
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:charger_circuit_bb.png?600 |}}
+</WRAP></WRAP>
+=== Connecting the RGB LED ===
+<WRAP group><WRAP half column>
+Finally, connect the RGB LED (and the current limiting resistors calculated to your LED) between the positive lead of the battery and the remaining three MOSFETs of the Pmod OD1. In this circuit, only RGB LEDs with separate anodes and cathodes, or with a common anode and separate cathodes can be used.
+</WRAP><WRAP half column>
+{{ :test-and-measurement:analog-discovery-pro-3x50:rgb_led_bb.png?600 |}}
+</WRAP></WRAP>
+</WRAP>
+----
+===== Software Setup =====
+<WRAP group>
+In the following, the structure of the main program file will be detailed. You can follow this guide to write your own control program based on the instructions given here, or you can download the source code {{ :test-and-measurement:analog-discovery-pro-3x50:lamp_controller.zip |here}}.
+=== Importing the Modules and Defining Connections ===
+<WRAP group><WRAP half column>
+To be able to use all the previously created modules, you must import them into your script.
+To make your code more readable and easier to debug, it is good practice to name your connections (so you don't have to keep in mind which digital, or analog channel is used for what).
+</WRAP><WRAP half column>
+<code python>
+# import modules
+from PMOD import DA1, BLE, ALS, OD1
+import WaveForms_HAL as WF
+import time
+"""-------------------------------------------------------------------"""
+# define connections
+# PMOD DA1 pins
+DA1.pins.sync = 3
+DA1.pins.d0 = 2
+DA1.pins.d1 = 1
+DA1.pins.sck = 0
+# Pmod OD1 pins
+OD1.pins.g1 = 7
+# PMOD BLE pins
+BLE.pins.rst = 4
+BLE.pins.rx = 5
+BLE.pins.tx = 6
+# PMOD ALS pins
+ALS.pins.cs = 10
+ALS.pins.sdo = 9
+ALS.pins.sck = 8
+# digital I/O
+signal_LED = 11
+# scope channels
+battery_neg_ch = 1
+battery_pos_ch = 2
+# wavegen channels
+current_reference = 1
+pwm_reference = 2
+# lamp color references
+lamp_red = DA1.output_channel.A1
+lamp_green = DA1.output_channel.B1
+lamp_blue = DA1.output_channel.A2
+# define low side switch (OD1 channel)
+low_switch = 1
+</code>
+</WRAP></WRAP>
+=== Global Variables and Auxiliary Functions ===
+<WRAP group><WRAP half column>
+Define the global parameters of your project. If you initialize these variables at the start of your code, it will be easier to modify them during tuning the finished project.
+Some auxiliary functions might be needed as well, which will be used later in the script.
+</WRAP><WRAP half column>
+<code python>
+# other parameters
+light_referesh = 2  # delay between refreshing the light intensity (in seconds)
+scope_average = 10  # how many measurements to average with the scope
+light_average = 10  # how many measurements to average with the light sensor
+battery_charged = 4.2   # battery charge level in volts
+battery_discharged = 3.7    # battery discharge level in volts
+max_charge_current = 0.1    # maximum charge current of the battery (in Amperes)
+"""-------------------------------------------------------------------"""
+def scale(value, source, destination):
+    # scale a number from a range to another
+    return ((value - source[0]) / (source[1] - source[0])) * (destination[1] - destination[0]) + destination[0]
+</code>
+</WRAP></WRAP>
+The "body" of the script is inserted in a try-except structure. This structure runs the code sequence in the "try" block, and if an error (exception) occurs, handles it as defined in the "except" block. In this case the "except" block is empty (the script just finishes when the Ctrl+C combination is pressed), but it is followed by a "finally" block, which runs only once, when the try-except structure is exited. Here, the cleanup procedure can be executed, which will be discussed later.
+=== Initialization ===
+<WRAP group><WRAP half column>
+To be able to use the instruments, you must initialize the HAL created previously, as well as the modules controlling the PMODs. After everything is initialized, start generating the reference signals on the Wavegen channels, but turn off the lamp and the signaling LED. You can also make the battery ground floating, by turning off the MOSFET used as a low-side switch.
+</WRAP><WRAP half column>
+<code python>
+    # initialize the interface
+    WF.initialize()
+    # initialize the scope with default settings
+    WF.scope.initialize()
+    # initialize the PMODs
+    DA1.initialize(WF)
+    OD1.initialize(WF)
+    ALS.initialize(WF)
+    BLE.initialize(WF)
+    BLE.reboot()
+    """---------------------------------"""
+    # start generating the reference signals
+    WF.wavegen.generate(current_reference, WF.wavegen.type.dc, 0)
+    WF.wavegen.generate(pwm_reference, WF.wavegen.type.ramp.up,
+.5, frequency=1e03, offset=0.5, symmetry=100)
+    """---------------------------------"""
+    # turn off the lamp
+    DA1.output_voltage(lamp_red, 1)
+    DA1.output_voltage(lamp_green, 1)
+    DA1.output_voltage(lamp_blue, 1)
+    # turn off the switch and the LED
+    WF.digital.set_output(signal_LED)
+    WF.digital.write(signal_LED, False)
+    OD1.off(low_switch)
+</code>
+</WRAP></WRAP>
+=== Endless Loop ===
+<WRAP group><WRAP half column>
+The main part of the script is run in an endless loop, which can be exited only by a keyboard interrupt. However, there are some states, which must be kept unchanged between iterations, so certain flags and variables must be initialized before the loop.
+</WRAP><WRAP half column>
+<code python>
+    # variables to remember states
+    start_time = time.time()
+    lamp_on = False
+    off_flag = True
+    charger_connected = False
+</code>
+</WRAP></WRAP>
+<WRAP group><WRAP half column>
+All other variables are temporal, they change in every iterations, so they can be defined in the loop.
+</WRAP><WRAP half column>
+<code python>
+        # temporal variables
+        BT_flag = False
+        battery_negative = 0
+        battery_positive = 0
+        light = 0
+</code>
+</WRAP></WRAP>
+=== Receive Data on Bluetooth Low Energy ===
+<WRAP group><WRAP half column>
+As a first step, read the messages from the PMOD BLE and save the connection status (also turn off the lamp if the module is disconnected). If the data is received without error, convert the received bytes to voltages, then set the lamp color, by setting the output values of the DAC channels.
+</WRAP><WRAP half column>
+<code python>
+        # read data from the Bluetooth module
+        data, sys_msg, error = BLE.receive_data()
+        data = list(data)
+        # turn the lamp on/off
+        if sys_msg.startswith("%CONNECT"):
+            lamp_on = True
+        elif sys_msg == "%DISCONNECT%":
+            lamp_on = False
+        # process the data
+        if error == "no error" and len(data) >= 3:
+            BT_flag = True
+            data = [ord(element) for element in data]
+            duty_red = scale(data[-3], [1, 255], [1, 0])
+            duty_green = scale(data[-2], [1, 255], [1, 0])
+            duty_blue = scale(data[-1], [1, 255], [1, 0])
+        # set lamp color according to received data
+        if lamp_on:
+            if BT_flag:
+                BT_flag = False
+                off_flag = False
+                DA1.output_voltage(lamp_red, duty_red)
+                DA1.output_voltage(lamp_green, duty_green)
+                DA1.output_voltage(lamp_blue, duty_blue)
+        else:
+            if not off_flag:
+                off_flag = True
+                DA1.output_voltage(lamp_red, 1)
+                DA1.output_voltage(lamp_green, 1)
+                DA1.output_voltage(lamp_blue, 1)
+</code>
+</WRAP></WRAP>
+=== Measuring the Light Intensity ===
+<WRAP group><WRAP half column>
+Light intensity is measured only after a predefined time interval. When it is needed, the PMOD ALS is used to measure the light intensity, then the result is encoded to a byte and sent using the Pmod BLE.
+</WRAP><WRAP half column>
+<code python>
+        # if the light intensity has to be measured
+        if time.time() - start_time > light_referesh:
+            # reinitialize the SPI interface
+            ALS.initialize(WF)
+            # measure the light intensity
+            for _ in range(light_average):
+                light += ALS.receive_percent()
+            light /= light_average
+            # encode the light intensity
+            encoded_light = round(light * 2.55) & 0xFF
+            # reinitialize the UART interface
+            BLE.initialize(WF)
+            # send light intensity
+            BLE.send_data(encoded_light)
+            start_time = time.time()
+</code>
+</WRAP></WRAP>
+=== Charging the Battery ===
+<WRAP group><WRAP half column>
+In every iteration of the main loop, measure the battery voltage. Also check, whether the charger is connected, or not and turn on the low-side switch, if the charger is disconnected, to ground the battery properly, but turn off the switch, when the charger is connected, to prevent any overvoltage on the battery cell. Set the charging current and turn the signaling LED on, or off according to the state of the charger circuit.
+</WRAP><WRAP half column>
+<code python>
+        # read battery voltage
+        for _ in range(scope_average):
+            battery_negative += WF.scope.measure(battery_neg_ch)
+        battery_negative /= scope_average
+        for _ in range(scope_average):
+            battery_positive += WF.scope.measure(battery_pos_ch)
+        battery_positive /= scope_average
+        battery_voltage = battery_positive - battery_negative
+        # decide if the charger is connected or not
+        if battery_positive >= 4.3:
+            charger_connected = True
+            OD1.off(low_switch)
+        else:
+            charger_connected = False
+            OD1.on(low_switch)
+        # calculate charge current reference
+        charge_current = max_charge_current * scale(battery_voltage, [battery_discharged, battery_charged], [0.5, 1])
+        charge_current_ref = scale(charge_current, [0, max_charge_current], [0, 1])
+        # start/stop charging
+        if charger_connected and battery_voltage < battery_charged:
+            WF.wavegen.generate(current_reference, WF.wavegen.type.dc, charge_current_ref)
+            WF.digital.write(signal_LED, True)
+        else:
+            WF.wavegen.generate(current_reference, WF.wavegen.type.dc, 0)
+            WF.digital.write(signal_LED, False)
+</code>
+</WRAP></WRAP>
+=== Cleanup ===
+<WRAP group><WRAP half column>
+When the script is finished, turn off the lamp and the charger, then close reset the used instruments and disconnect from the device.
+</WRAP><WRAP half column>
+<code python>
+    # turn off the lamp
+    DA1.output_voltage(lamp_red, 1)
+    DA1.output_voltage(lamp_green, 1)
+    DA1.output_voltage(lamp_blue, 1)
+    # turn off the LED and the switch
+    WF.digital.write(signal_LED, False)
+    OD1.off(low_switch)
+    # close PMODs
+    ALS.close()
+    BLE.close()
+    DA1.close()
+    OD1.close()
+    # close device
+    WF.close()
+</code>
+</WRAP></WRAP>
+</WRAP>
+----
+===== Tuning and Testing =====
+<WRAP group>
+Start the script, then start the application on your phone. Wait until the phone discovers the PMOD BLE, then connect to it. Set the lamp color and luminosity on the sliders of the application.
+If you want to modify the parameters of the script, stop it with Ctrl+C, modify the parameters, then restart the script. Averaging more measurements leads to a more stable result, with a slower update time.
+Take care not to overcharge, or over-discharge the battery, or overload the power supply.
+</WRAP>
+----
+===== Next Steps =====
+<WRAP group>
+For more information on WaveForms SDK, see its [[software:waveforms:waveforms-sdk:start|Resource Center]].
+For technical support, please visit the [[https://forum.digilentinc.com/forum/8-test-and-measurement/|Test and Measurement]] section of the Digilent Forums.
+</WRAP>

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