Talk:Raspberry Pi

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Differentiating RPi versions

Would it be worth it to either split out version-specific instructions, or perhaps make the instructions more agnostic to version? I just got an RPi 3, for example, and am pretty sure Raspberry_Pi#I2C is not applicable:

i2c-bcm2708

I only load i2c-bcm2835, for example, and my Sense Hat functions properly. I'm just getting started with the RPi using Arch, so in seeing this page for the first time, it looks like it mixes and matches various drivers, possibly based on who was adding the instructions at the time. In the section on the Raspberry_Pi#Raspberry_Pi_camera_module, a fix is proposed to blacklist i2c_bcm2708, followed by another fix which is to load bcm2835-v4l2. I wondered if these are separate fixes for the RPi 2 vs. 3, respectively?

Jwhendy (talk) 23:10, 24 September 2017 (UTC)

Please discuss this contribution with the ALARM wiki team as described in [1]. Thank you. -- Alad (talk) 23:51, 24 September 2017 (UTC)
Will do. I think it would be helpful for posterity's sake to post something like "this entire wiki was not meant to exist." I found it confusing to be directed to that link, as it didn't mention anything about this wiki. Now I assume that this page was like a "fork" that really shouldn't have been here. Out of curiosity, why keep all of the other platform pages? In any case, now that I'm pointed in the right direction, I'll definitely bring these suggestions up. Thanks! Jwhendy (talk) 14:19, 25 September 2017 (UTC)
If anyone else stumbles here, this is going to carry on here on github. Jwhendy (talk) 14:32, 25 September 2017 (UTC)

Adjustments to I2C section

I just started fiddling with my RPi 3 and found the I2C setup very frustrating. I can make these edits, but would rather those more familiar with RPi with Arch Arm chime in first. Some observations:

- I believe this is only applicable for early RPi's.

# i2cdetect -y 0

This adafruit article says that i2c-0 is for 256mb Pis and i2c-1 is for 512mb Pis.

- This code was unclear to me:

# echo <devicename> <hardware address> >/sys/class/i2c-adapter/i2c-0/new_device

If this is necessary for something, it might be best to just give a full example. When I run i2cdetect, I get 5 addresses; how does one know what's what and what to add?

- I ran into errors trying to use my Sense Hat and it turned out it was all due to permissions on /dev/i2c-1. I ended up adding this:

/etc/udev/rules.d/99-i2c.rules
KERNEL=="i2c-[0-7]",MODE="0666"

The errors were quite cryptic ("unable to initialize humidity sensor"), so I thought I hadn't loaded the right module. I've seen various ways to apply a udev rule; maybe this is not desired and one should apply it to the device for security/safety?

Jwhendy (talk) 23:10, 24 September 2017 (UTC)

Please discuss this contribution with the ALARM wiki team as described in [2]. Thank you. -- Alad (talk) 23:51, 24 September 2017 (UTC)