I have a circuit on a breadboard. It has an I2C LCD and HMC5883L magnetometer.
I added a 24C64 EEPROM and got that working.
Then I realised that the project could use a RTC so I got a DS3231 RTC module which also has a 24C32 EEPROM (which is big enough.
The problem is that neither of these two respond on the I2C.
I2C Addresses:
LCD 0X4E/0x4F
HMC5883L 0x3C/0x3D
Expected addresses:
DS3231 0xD0/0xD1
24C32 0xA0/0xA1
I wrote an I2C scan routine - sends the address and checks for an ACK. This routine got an ACK from addresses:
0x3C, 0x3D which matches the HMC5883L
0x4E, 0x4F which matches the LCD
Other addresses whick responded:
0X3E, 0x50, 0x51, 0x53, 0x53 but I don't know what these are.
Note: no response from 0xD0, 0xD1, 0xA0, 0x A1 which should be the RTC module addresses.
I have tried two similar RTC modules with the same results.
Any ideas what is going on here?
I added a 24C64 EEPROM and got that working.
Then I realised that the project could use a RTC so I got a DS3231 RTC module which also has a 24C32 EEPROM (which is big enough.
The problem is that neither of these two respond on the I2C.
I2C Addresses:
LCD 0X4E/0x4F
HMC5883L 0x3C/0x3D
Expected addresses:
DS3231 0xD0/0xD1
24C32 0xA0/0xA1
I wrote an I2C scan routine - sends the address and checks for an ACK. This routine got an ACK from addresses:
0x3C, 0x3D which matches the HMC5883L
0x4E, 0x4F which matches the LCD
Other addresses whick responded:
0X3E, 0x50, 0x51, 0x53, 0x53 but I don't know what these are.
Note: no response from 0xD0, 0xD1, 0xA0, 0x A1 which should be the RTC module addresses.
I have tried two similar RTC modules with the same results.
Any ideas what is going on here?