Re: Howto read I2C on MPC5200 Lite
From: John Rigby <hidden>
Date: 2007-03-09 17:11:20
The some 5200's have had a problem with a missing clock pulse on scl. The latest ppc tree plus Doman Puncer's i2c patch of a few days ago http://article.gmane.org/gmane.linux.ports.ppc.embedded/15718/match=3Di2c should fix the problem if that is it. On 3/9/07, Matthias Fechner [off-list ref] wrote:
Hello John, * John Rigby [off-list ref] [07-03-07 14:17]:quoted
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 =B0C. That worked fine, but after reading the value some time, the I2C bus is dead. The kernel says: i2c_adapter i2c-1: ioctl, cmd=3D0x705, arg=3D0x7feaf8ec i2c_adapter i2c-1: ioctl, cmd=3D0x706, arg=3D0x40 i2c_adapter i2c-1: ioctl, cmd=3D0x720, arg=3D0x7feaf8f0 i2c_adapter i2c-1: master_xfer[0] W, addr=3D0x40, len=3D1 i2c_adapter i2c-1: master_xfer[1] R, addr=3D0x40, len=3D2 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 _______________________________________________ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded