I have an I2C bus with a PIC6621 master and a 24LC512 EEPROM slave. It is working. I am trying to add a DS1307 and a DS2482 to the I2C bus, but I can't get any response from either of the latter. I can see the SCL and SDA lines on my Optascope (and admittedly, the Optascope just barely has the power to see a
100 kHz signal). When I send the I2C address, I can verify the 8 bit pattern of SDA, but when the slave is supposed to send an ACK by holding SDA low, all I see is a high NACK pulse instead. It appears that the slave is not responding, or choosing to send a NACK. I have verified the addressing of the DS1307 (0xD0) and the DS2482 (0x30), so I'm stuck. Any suggestions are welcome.- posted
18 years ago