Howto read I2C on MPC5200 Lite

Matthias Fechner idefix at fechner.net
Fri Mar 9 22:35:07 EST 2007


Hello John,

* John Rigby <jrigby at freescale.com> [07-03-07 14:17]:
> On a stock lite5200b the only thing that shows up is a serial
> eeprom at address 0x50.

thx a lot, that tool helped me a lot.
I have written a very small c-program to access the I2C bus to read the
temperature of my MAX6633 and convert it to °C.

That worked fine, but after reading the value some time, the I2C bus
is dead. The kernel says:
i2c_adapter i2c-1: ioctl, cmd=0x705, arg=0x7feaf8ec
i2c_adapter i2c-1: ioctl, cmd=0x706, arg=0x40
i2c_adapter i2c-1: ioctl, cmd=0x720, arg=0x7feaf8f0
i2c_adapter i2c-1: master_xfer[0] W, addr=0x40, len=1
i2c_adapter i2c-1: master_xfer[1] R, addr=0x40, len=2
I2C: timeout

Is that maybe a bug in the I2C driver (i2c-mpc) or is my programm
faulty?
If it helps I can attach the programm.

Best regards,
Matthias

-- 

"Programming today is a race between software engineers striving to
build bigger and better idiot-proof programs, and the universe trying to
produce bigger and better idiots. So far, the universe is winning." --
Rich Cook



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