search

monome / norns-image

79 stars 16 forks source link

GPIO Pins incorrect? #49

Closed okyeron closed 6 years ago

okyeron commented 6 years ago

GPIO Pins are listed here: https://github.com/monome/norns-image/blob/master/readme-hardware.md

This is confusing as I think what's listed is the actual pin # rather than the GPIO#

Also - Pin 39 (GPIO39 as listed) is GND

Are these the correct assignments? Where is the dt_overlay for these?

Here's a reference image showing pin number as well as GPIO# image

catfact commented 6 years ago

norns uses the compute module (cm3) which has more IO and different pinout (on 200-pin SODIMM connector.)

https://www.raspberrypi.org/documentation/hardware/computemodule/datasheets/rpi_DATA_CM_1p0.pdf

https://www.raspberrypi.org/documentation/hardware/computemodule/schematics/rpi_SCH_CM3_1p0.pdf

that said, does seem like there are some errors (e.g., GPIO02 and GPIO03 alt funcs are i2c0, not i2c1)

(grain of salt: i'm not the hardware designer, so i could be misunderstanding that.)

kernel overlays aren't available just yet.

okyeron commented 6 years ago

Aha! That certainly explains my confusion.

Hoping there is a way to map the GPIOs to a RasPI 3 sometime soon. Also - I'm happy to help with testing or whatever might needed there.

FWIW - it might be worth noting on that page that those are the pinouts for the cm3

tehn commented 6 years ago

does seem like there are some errors (e.g., GPIO02 and GPIO03 alt funcs are i2c0, not i2c1)

just checked the doc, it lists i2c0? didn't see any errors, checked against schem just now but please let me know if you see anything wrong

catfact commented 6 years ago

sorry sorry sorry typo, i meant the other way round. doc says

    PIN: SDA = GPIO2
    PIN: SCL = GPIO3

datasheet table 9.1.1 alt funcs says

GPIO0 - SDA0
GPIO1 - SCL0
GPIO2 - SDA1
GPIO3 - SCL1

again i could be misunderstanding