add custom constraints to HDL coder

Question

My Simulink project is now progressing steadily!

Compatibility for the Digilent AD2 PMOD peripheral is now working but my programming procedure make use of a trick which I would like to avoid.

Because I need to add constraints for internal pullups I tipically stop the workflow after RTL generation, include the constraints in the .xdc file automatically generated and then proceed with the bitstream generation.

I do this ugly thing because Simulink doesn't seem to offer the possibility to add PULLUP constraints to the system port.

Then i saw in the MiniZed compatibility package an .xdc file for the wifi pins.

Could I add my constraints to this file and expect to be picked-up at each generation?

Is there a truly elegant way of doing this?

mbrown · Accepted Answer

Glad to hear you're making progress!

You can add custom constraints in two ways:

1) Add them to the .xdc you found in the MiniZed add-on folder (your current method):

C:\Users\<user>\Documents\MATLAB\Add-Ons\Toolboxes\Avnet MiniZed Support Package for Simulink\code\hdlcoder\MiniZed\+MiniZedRegistration\+Vivado2017_2\minized_wifi_pins.xdc

2) You should also be able to add an additional .xdc constraints file for HDL Workflow Advisor. Just add it to

C:\Users\<user>\Documents\MATLAB\Add-Ons\Toolboxes\Avnet MiniZed Support Package for Simulink\code\hdlcoder\MiniZed\+MiniZedRegistration\+Vivado2017_2\plug_rd.m

% Add custom Vivado constraints
hRD.CustomConstraints = {'minized_wifi_pins.xdc', 'PMOD_pins.xdc'};