Connecting a custom SPI device to Duet3+SBC

pjl · 3 Jul 2022, 09:22

Greetings and salutations,

My goal is to connect a little SPI camera to duet+sbc, images from which will then be processed by the SBC.

As I see in the wiring diagram Duet3 6HC has two SPI buses, one for SBC, the other for temperature daughterboard and raspberry has two SPI buses available in the 40pin GPIO.

Question 1: Can I safely hijack the SPI1 bus from the Raspberry for my own use? Since it looks like only SPI0 is used by the Duet.

Question 2, general curiosity : Could I connect any device through the SPI bus meant for the temperature daughterboard on the Duet?

achrn · 7 Mar 2022, 15:38

Q1: yes (probably)

I use the Pi other SPI bus for driving a string of APA102 LEDs. I'm driving the bus at 10 MHz. Since it's the only SPI device I have on that bus, I don't have a CS line connected. Also it's one-way comms (nothing coming back into the Pi) so I don't use a MISO. Accordingly I just use pins 38 & 40.

So it works for me, but my situation is simpler than yours is likely to be.