> The GPIO pins could be bidirectional, but one way at a time. Meaning, > the read value _GPIO_Y_0 is not valid when _GPIO_EN_0 is set. I did not see anything similar in Gatos' code. > Also, I did not find _GPIO_A_0 (nor _1) initialised to 0 in your code. > I believe this is the value ( 0 = pull low, 1 = hi-Z ) when _GPIO_EN_0 > is set. Makes sense with the inverted setscl&sda. I did that, it did not help. I believe that both bits were 0 anyway -- the whole register value is 0. > Did you try without bit_test? You might need some <1 us delay between > read and write to see the change, the bus has some capacitance even > without monitor cable. Yes, I tried without bit_test=1. I2cdetect hangs using 100% CPU, which makes me think my code is somehow broken, although I don't see where. I've copied what I read from the gatos code, using i2c-savage4 as a base, everything seems very simple, but it doesn't work. Would you have any concrete suggestion of something I could try? Else I think I'll just give up. Thanks. -- Jean Delvare http://www.ensicaen.ismra.fr/~delvare/
