DS1077
SLAVE ADDRESS
A control byte is the first byte received following the START condition from the master device. The
control byte consists of a 4-bit control code; for the DS1077, this is set as 1011 binary for read and write
operations. The next three bits of the control byte are the device select bits (A2, A1, A0) and can be
written to the EEPROM. They are used by the master device to select which of eight devices are to be
accessed. The select bits are in effect the three least significant bits of the slave address. The last bit of the
control byte (R/ W ) defines the operation to be performed. When set to a one a read operation is selected,
and when set to a zero, a write operation is selected. Following the START condition, the DS1077
monitors the SDA bus, checking the device type identifier being transmitted. Upon receiving the 1011
code (changeable with one mask) and appropriate device select bits, the slave device outputs an
acknowledge signal on the SDA line.
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DALLAS [ DALLAS SEMICONDUCTOR ]
