Posted on March 15, 2015 at 14:11Slave parts have fixed, default addresses, which are usually adequately unique/diverse to allow a system to use a lot of different devices. Refer to the manual for the slave parts, and if they have an address select pin to pick between one address, and others.
The 7-bit addressing is the high order bits, so some parts will refer to the address as say 0x25, the value programmed into the command request would be 0x4A. Look carefully at the diagrams in the part manual. The slave address is the first byte sent to the device, if a device on the bus recognizes the address it drives ACK low. At that point other devices stand down, or you determine no device with that address exists on the bus.
