Aidos
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I2C0 on CM3

Fri Sep 15, 2017 4:46 pm

Hi all,

I want use CM3 with Raspberry 7" LCD.
My question is: which GPIO should I use for SCL0 and SDA0 signals?

SCL1 is at GPIO3 and SDA1 is at GPIO2 normally, where are SCL0 and SDA0 normally? (when I use Pi Model A+ the LCD works with standard Raspbian).

In other words I want know which are the GPIO used on Pi Model A+ for SCL0 and SDA0.

Thank you!

ShiftPlusOne
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Re: I2C0 on CM3

Fri Sep 15, 2017 5:44 pm

Aidos wrote: In other words I want know which are the GPIO used on Pi Model A+ for SCL0 and SDA0.
https://github.com/raspberrypi/firmware ... b.dts#L571

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rpdom
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Re: I2C0 on CM3

Fri Sep 15, 2017 6:59 pm

For the A+ I would look at https://pinout.xyz

I2C0 SDA is GPIO 0 on pin 27 (ID_SD) and I2C0 SCL is GPIO 1 on pin 28 (ID_SC)

6by9
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Re: I2C0 on CM3

Fri Sep 15, 2017 9:19 pm

Why not read the documentation? https://www.raspberrypi.org/documentati ... display.md

The GPIO usage on an A+ is pretty irrelevant to the CM. If you're really bothered, then it's GPIOs 28&29 as documented in the dt-blob.dts that ShiftPlusOne linked to.
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Aidos
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Joined: Fri Sep 15, 2017 4:32 pm

Re: I2C0 on CM3

Sat Sep 16, 2017 7:53 am

Hi all,
Thank you for your reply, now I understand and it is more clear.

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