Problems after power cycle (i2c unavailable, inputs missing...)

butako1 · 2021-11-23T20:18:36.470Z

I had an electrician round and he tripped the RCD several times in quick succession. Now, my emonPi is not very happy. It boots up OK, I can access the Web and SSH OK, however the inputs and i2c are missing. On the Web UI Inputs page all the inputs are shown with a red “n/a”.

The only error in syslog that I see is:
I2C LCD NOT DETECTED on either 0x[‘27’, ‘3f’] …exiting LCD script

So trying some detective work:-

$> i2cdetect -y 1
Error: Could not open file /dev/i2c-1' or /dev/i2c/1’: No such file or directory

$> lsmod | grep i2c
i2c_dev 20480 0

Any ideas how to fix, please?

I thought the SDCard could be corrupted but it is booting OK and no other errors are visible in syslog.

Thanks

TrystanLea · 2021-11-23T21:30:49.917Z

Hello @butako1 Im not sure how to fix the i2c errors, might be worth searching general linux/raspberrypi forums to see if anything comes up. For the inputs, can you see anything in the emonhub log?

butako1 · 2021-11-23T22:10:33.552Z

Hi @TrystanLea thanks for taking a look. I bit the bullet and reinstalled the SD card with a clean fresh image. It now appears to be working again. I managed to make a backup, and restored it too, so far so good. Phew!