[En-Nut-Discussion] TWI aka I2C, not getting an ACK back?

[Harald Kipp]

Hi Douglas,

At 16:30 16.03.2005 +1300, you wrote:

>    rc = writeRTC(sla,0x0E,dataRTC,2); //on the i2c bus I get "<start> 
> 110100000 <SDA goes high>  000000000  000000000 000000000<stop>
>//where did the 0x0E go which should have been immediately after <SDA goes 
>high>
>//I checked the wrteRTC routine and it does pass 0x0E 0x00 0x00 in the 
>'data field to TwMasterTransact

What about hardware? You are aware, that I2C is open
drain? Did you add pull-ups? Anything else connected,
which may drive the bus low?

Harald