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Topic: WrtNode i2c error

The content of this topic has been archived on 16 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hello everybody,

I am going to use i2c and then I compiled my firmware for wrtnode using with this document.
http://wiki.wrtnode.com/index.php?title … 2c_support

Did everything in this document but i'm taking an error when using 'i2cdetect 0' command. Output of this command not make sensible. The output is below. While the command processing, terminal screen gives me an error message 'i2c transfer failed.'

root@OpenWrt:~# i2cdetect 0
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will probe file /dev/i2c-0.
I will probe address range 0x03-0x77.
Continue? [Y/n] y
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f
10: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f
20: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f
30: 30 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f
40: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f
50: 50 51 52 53 54 55 56 57 58 59 5a 5b 5c 5d 5e 5f
60: 60 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f
70: 70 71 72 73 74 75 76 77   

Anyone knows what is the problem, or any idea how can i beat this issue?

Thx for your advices.

I had experienced such behavior (on a different platform) when my wiring was bad, IIRC. So, I would recommend to double check the right pins (SDA/SCL switched?),  pull-up resistors in place, soldering, resistence of wires and possible short circuits.

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