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Gadgeteer Daisy Chaining Project (Request for help)


#21

So those things are already busses on a Gadgeteer device, and are usable as-is.
For SPI, you need a CS (“Chip Select” per device on the bus. So it’s not simple to truly daisy chain an infinite number of devices on, because your wire count has to go up with the number of devices. You could theoretically support X devices if you had your power/ground signals, plus the clock and data lines, plus X CS lines.
For I2C, you just need unique addresses, so as long as your additional nodes each have their own address, it’s easy.
Same for one-wire, they use addresses so as long as you use unique addresses (which you could buy chips for), they should be simple to implement.

But only part of your challenge is the logical aspect, part will be the physical. I believe that Gadgeteer suffered some limitations specifically because they were shoehorning a set of wires into each connector to cater for “common denominator” configurations. You only get a maximum of 7 signal wires and power options, and for SPI for example you couldn’t easily assign a different signal wire as the CS, meaning an SPI socket was consumed for just one SPI device. You get to break some of that since you’re designing your own approach (from what I read in your task brief) so figuring out what your requirements are will be important


#22

Thank you for your advice. I am still doing research into the communication protocols as I am relatively new to them.