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7: Synchronous Communication > Notes for the C Experts - Pg. 136

136 l Chapter 7 l l To keep the bus overhead low (using only one byte of address after the command byte), devices with capacity between 512 bytes and 2 Kbytes (04 to 16) use three bits of the command byte (in violation of the standard) to carry from one to three bits of the address (marked as B0/B1 and B2). As a consequence, the device addressing is incomplete and only one device can be connected to the bus. Memory sizes at or above 4 Kbytes require a second address byte following the command byte. The write buffer (page) size grows somewhat linearly with the size of the array, but there are notable exceptions, watch out! The SEE24.c module presented recently was designed for the 24xx16B type of Serial EEPROM, a device that you will find right in the middle of the table and, as you can see, perhaps not representing the most generic case. Depending on the memory size required by your application you will need to: l Apply minor changes to the addressSEE() function (adding a second address byte and moving the msb address bits there) or in case you are planning to use the smallest devices available (24xx00) that do not offer a write (page) buffer: