2nd I2C Bus Occasionally Fails

figsys

Have been running Ubilinux and MRAA 1.9.0 and using both I2C ports to talk to 2 seperate devices (1 per I2C bus). However, occasionally the second I2C (on pins 27/28) fails on typically first read operation - here's the error in the journal file

Jul 12 19:08:54 ubilinux4 libmraa[1880]: i2c_init: Selected bus 1
Jul 12 19:08:54 ubilinux4 libmraa[1880]: i2c0: write_byte: Access error: Remote I/O error

Normal operation is something like this

Jul 12 19:49:27 ubilinux4 libmraa[4334]: Adding i2c bus found on i2c-1 on adapter .
Jul 12 19:49:27 ubilinux4 libmraa[4334]: Adding i2c bus found on i2c-0 on adapter .
Jul 12 19:49:27 ubilinux4 libmraa[4334]: i2c_init: Selected bus 0
Jul 12 19:49:27 ubilinux4 libmraa[4334]: i2c_init: Selected bus 1

Need a restart to get this to work. Anyone else experience this issue or has used both buses with no issues? Anything else to look for to troubleshoot?

ccalde

Hi @figsys ,

1) What is the BIOS version you are using there?
2) Did you install the last Ubilinux version including the MRAA? https://emutex.com/products/ubilinux
2) Did you see that issue using only one port at the same time?

Thank you!

figsys

@ccalde said:
Hi @figsys ,

1) What is the BIOS version you are using there?
2) Did you install the last Ubilinux version including the MRAA? https://emutex.com/products/ubilinux
2) Did you see that issue using only one port at the same time?

Thank you!

BIOS Revision 5.11
Linux version 4.9.45-ubilinux+
MRAA Version: v1.9.0-48-gc563e4f

Issue never happens when running only port 0. Also happens when running only port 1 but most of our failure data is for running both ports.

Thanks!