On the picocom terminal, you can control the counter behaviour to stop it, or let it count backwards, by toggling values of the EMIO pins of the ARM Processing System (PS).
You can control the counter enable signal with:
gpio set 54
gpio clear 54
If GPIO 54 is set, the counter is disabled. It is enabled if the GPIO 54 is cleared. The result should be as follows:
(image)
I build the counter test, scp top.bit to the pi, load it:
openFPGALoader -b arty top.bit
The lights blink as expected, so it is loaded. But this doesn't echo anything and I suspect it isn't working:
picocom /dev/ttyUSB1
I type gpio set 54 and nothing echos and the lights keep blinking.
mithro
commented
2 months ago
https://github.com/CarlFK/pici/wiki/Getting-Started links to https://f4pga-examples.readthedocs.io/en/latest/xc7/counter_test.html which says
I build the counter test, scp top.bit to the pi, load it:
The lights blink as expected, so it is loaded. But this doesn't echo anything and I suspect it isn't working:
I type
gpio set 54and nothing echos and the lights keep blinking.