Looking to control a relay from the Rainbow HAT and need access to a single pin to write high or low to control a relay. It looks like there are some other pins left over from the HAT, but the HAT blocks access to all of the pins so I was hoping to use one of the ones on the HAT.
Thanks.
Im using the NXP Pico i.MX7D not the Raspberry pi if that helps.
The SPI pins MOSI, MISO, and SCLK may be able to be reconfigured as GPIO. They are GPIO 10, 9 and 11. Assuming they are just wired straight through to the header on the Rainbow Hat. And its not used by the Rainbow Hat. I would think i2c is used and you wouldn’t want to use that for anything else than i2c.
@gadgetoid likely knows what’s used and what’s not.
Another option, one I use all the time, is to mount a proto hat on a stacking header and plug that in between the Pi and Rainbow Hat. The proto board breaks out the GPIO pins to solder pads.