BASYS3 FPGA pin planning and configuration question

Question

I have designed a basic 8-bit CPU that is mapped onto FPGA fabric on a Digilent BASYS3 development board. The DRC results in a few error messages that I do not understand, with one of them being shown in the image below:

Now I have found where I set these values as shown below:

My question is: What is this error message really saying, and where do I find out what to set these parameters at? I have looked at the reference manual for the BASYS3 but don't see anything given there. Or do I find this on the Artix 7 FPGA chip datasheet instead?

EDIT

Thanks to Colorado.Rob for pointing this out. I should have mentioned in the question that I do have a constraints file in the project as below:

# This file is a general .xdc for the Basys3 rev B board
# To use it in a project:
# - uncomment the lines corresponding to used pins
# - rename the used ports (in each line, after get_ports) according to the top level signal names in the project

# Clock signal
set_property -dict { PACKAGE_PIN W5   IOSTANDARD LVCMOS33 } [get_ports Clock_fpga_i]
create_clock -add -name Clock_fpga_i -period 10.00 -waveform {0 5} [get_ports Clock_fpga_i]

# LEDs
set_property -dict { PACKAGE_PIN U16   IOSTANDARD LVCMOS33 } [get_ports {led0_o}]
set_property -dict { PACKAGE_PIN E19   IOSTANDARD LVCMOS33 } [get_ports {led1_o}]
set_property -dict { PACKAGE_PIN U19   IOSTANDARD LVCMOS33 } [get_ports {led2_o}]
set_property -dict { PACKAGE_PIN V19   IOSTANDARD LVCMOS33 } [get_ports {led3_o}]
set_property -dict { PACKAGE_PIN W18   IOSTANDARD LVCMOS33 } [get_ports {led4_o}]
set_property -dict { PACKAGE_PIN U15   IOSTANDARD LVCMOS33 } [get_ports {led5_o}]
set_property -dict { PACKAGE_PIN U14   IOSTANDARD LVCMOS33 } [get_ports {led6_o}]
set_property -dict { PACKAGE_PIN V14   IOSTANDARD LVCMOS33 } [get_ports {led7_o}]

#Buttons
set_property -dict { PACKAGE_PIN U18   IOSTANDARD LVCMOS33 } [get_ports Reset_button_i]

Because I didn't copy the whole constraints file as you are probably supposed too, I didn't have these configuration lines that were at the bottom of the file:

So I copied them in as Colorado.Rob said and problem solved!

Hope this helps others out there.

Answer 1

You need a constraints file which properly specify the voltage of the pins used in the design. Grab the BASYS3 board XDC file. Copy that into your project (add it as a source) and un-comment all of the pins used.