This repository contains the FPGA implementation and example designs for the Tang Nano/Primer series of FPGA boards. For more information see the main repository.
The example design generates a 16 bit counter, that then can be verified on the host. With a small modification to the clk_data process in the top-file of your respective FPGA board you can stream your own payload data.
Currently, the bitfiles must be generated with the GOWIN IDE (V1.9.9 Beta-4 Education). See here for more information on how to set up the IDE.
In the future, it might be possible to use the Open Source toolchain (Yosys + nextpnr-himbaechel + apicula). This is currently blocked by the lack of the CLKDIV primitive in the Open Source tools.
The bitfile can be either loaded with the GOWIN Programmer, or with openFPGALoader.
Here is an example commandline for loading the bitfile on a Tang Nano 20K:
openFPGALoader -b tangnano20k hsdaoh_nano20k_test.fs
After loading the bitfile, connect the FPGA board to a MS2130 HDMI grabber and confirm that the video output is working. You then can use hsdaoh_test to verify the counter values.
The hsdaoh FPGA design was developed by Steve Markgraf, and is heavily based on the HDMI IP core by Sameer Puri and also uses the asynchronous FIFO by Damien Pretet.