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XDC Formatting Info
This Guide is to standardize our format for XDCs. All Digilent XDCs should follow this format to help ease the transfer of projects between boards.
GPIO
Switches
All switches should designated by a lower case sw as seen below. The ports should be numbered from 0 to NUMBER_OF_SWITCHES. This will let the user use the name as a bus. Example of 8 LEDs
[get_ports { sw[0] }];
[get_ports { sw[1] }];
[get_ports { sw[2] }];
[get_ports { sw[3] }];
[get_ports { sw[4] }];
[get_ports { sw[5] }];
[get_ports { sw[6] }];
[get_ports { sw[7] }];
LEDs
All LEDs should designated by a lower case led as seen below. The ports should be numbered from 0 to NUMBER_OF_LEDs. This will let the user use the name as a bus. Example of 8 LEDs
[get_ports { led[0] }];
[get_ports { led[1] }];
[get_ports { led[2] }];
[get_ports { led[3] }];
[get_ports { led[4] }];
[get_ports { led[5] }];
[get_ports { led[6] }];
[get_ports { led[7] }];
Buttons
RULD Buttons
All LEDs should be designated by a lower case “btn” then the indicator of the position of the button
[get_ports { btnc }];
[get_ports { btnd }];
[get_ports { btnl }];
[get_ports { btnr }];
[get_ports { btnu }];
Inline Buttons
All LEDs should be designated by a lower case “btn” then the indicator of the position of the button
[get_ports { btn[0] }];
[get_ports { btn[1] }];
[get_ports { btn[2] }];
[get_ports { btn[3] }];
CPU Reset Button
The active high reset button (if applicable) will be named “cpu_resetn”
[get_ports { cpu_resetn }];
Pmod Headers
The pmod headers will be designated by Jx where x is the letter specifying which header is used. The ports should be numbered from 0 to 7. This will let the user use the name as a bus.
[get_ports { jx[0] }];
[get_ports { jx[1] }];
[get_ports { jx[2] }];
[get_ports { jx[3] }];
[get_ports { jx[4] }];
[get_ports { jx[5] }];
[get_ports { jx[6] }];
[get_ports { jx[7] }];
XADC Pmod Headers
The XADC pmod headers will be designated by xa_n or xa_p and numbered from 0 - 3 to be used as a bus.
[get_ports { xa_n[0] }];
[get_ports { xa_p[0] }];
[get_ports { xa_n[1] }];
[get_ports { xa_p[1] }];
[get_ports { xa_n[2] }];
[get_ports { xa_p[2] }];
[get_ports { xa_n[3] }];
[get_ports { xa_p[3] }];
UART Interface
The two Uart signals will be named as follows
[get_ports { uart_rx_out }];
[get_ports { uart_tx_in }];

