> In the event that you ruin the board just let me know and I'll send > you another. I'll try not to need another one that soon ;) > The SMBus/I2C signal is generated by bit bashing the parallel port. OK, that's how I had understood it. > >I guess it's a simple problem of writing the right things at the > >right time on the parallel port. > > Yes. So I took our i2c-pport driver, which is intended for parallel-port bit-bashing. I had to adapt it to match the schematic I found on the evaluation CD. It now writes SCL to pin 2 (DATA bit 0), SDA to pin 3 (DATA bit 1) and reads SDA from pin 13 (STAT bit 4). I also added code to set pins 6 to 9 (DATA bits 4 to 7) to high so that the board gets enough power. According to the schematic, I don't think there is anything else required. I have somewhat good results, since: 1* The power led lights up. 2* The bit_test option of our i2c-algo-bit module (which I had to tweak a bit because the eval board doesn't let me read SCL back) suggests that SDA can be set and read back correctly. 3* When running some commands on the bus (using i2cdetect for example) I detect electrical activity on both SDA and SCL. I'm using a low-cost multimeter, unfortunatelly I don't have anything better to watch the signals. I'd love a good oscilloscope these days :/ Now the problem is: i2cdetect doesn't detect anything. Not a single chip. Running i2cdump on address 0x4c (where I know the adm1032 has to be) fails reporting a single valid byte too. It looks like the adm1032 doesn't want to answer, and I can't understand why. I've attached the modified i2c-pport.c source (BTW this module would benefit a complete rewrite someday, it's full of tricks that are better avoided in kernel code IMHO) in case someone has an idea of what I might be doing wrong. Sean, is there something I'm supposed to do that does not appear on the schematic? Some pin of the parallel port that must be forced to either high or low for proper operation? I'm kind of lost now. I was expecting everything to work OK once I'd have worked the bit-bashing driver out, and am diappointed that it still doesn't work. Your Windows tool being working on the same machine, I know that there is no hardware incompatibility, so that must be something I am doing wrong somewhere. I've even been trying various speeds, but it did not help. Thanks. -- Jean Delvare http://www.ensicaen.ismra.fr/~delvare/ -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: i2c-pport.c Url: http://lists.lm-sensors.org/pipermail/lm-sensors/attachments/20031030/b2776a5d/attachment.c
