On Fri, Apr 16, 2004 at 03:54:19PM +0200, Jean Delvare wrote: > For this reason, I can hardly understand how it was decided that this > command would be used for address probing purposes. I agree that the > SMBus spec has no provision for address probing, so we have to use > another command to achieve this purpose, still I would expect a > "receive byte" (I2C_FUNC_SMBUS_READ_BYTE) to be way safer than a "quick > command". The only side effect I can think off is that it would > increase the address pointer for chips in autoincrement mode, but > that's about all and it doesn't seem to hurt, really. In recent discussion about IBM IIC I mentioned that I had a hw were 1-byte read scan locked the bus. I just rechecked IBM PPC 440GP ref platform "Ebony" and indeed it has an i2c device which behaves this way. According to Ebony manual it's a CDC850 clock buffer (i2c address 0x69). To recover the i2c bus I have to reset the whole board, not just I2C controller. Just my $.02 Eugene.
