IN24LC04B/08B
Figure 5. Control Byte Allocation
WRITE OPERATION
Byte Write
Following the start condition from the master, the device code (4 bits), the block address (3 bits),
and the R/W bit which is a logic low is placed onto the bus by the master transmitter. This indicates
to the addressed slave receiver that a byte with a word address will follow after it has generated an
acknowledge bit during the ninth clock cycle. Therefore the next byte transmitted by the master is
the word address and will be written into the address pointer of the IN24LC04B/08B. After
receiving another acknowledge signal from the IN24LC04B/08B the master device will transmit the
data word to be written into the addressed memory location. The IN24LC04B/08B acknowledges
again and the master generates a stop condition. This initiates the internal write cycle, and during
this time the IN24LC04B/08B will not generate acknowledge signals (see Figure 6).
Page Write
The write control byte, word address and the first data byte are transmitted to the IN24LC04B/08B
in the same way as in a byte write. But instead of generating a stop condition the master transmits
up to sixteen data bytes to the IN24LC04B/08B which are temporarily stored in the on-chip page
buffer and will be written into the memory after the master has transmitted a stop condition. After
the receipt of each word, the four lower order address pointer bits are internally incremented by one.
The higher order seven bits of the word address remains constant. If the master should transmit
more than sixteen words prior to generating the stop condition, the address counter will roll over
and the previously received data will be overwritten. As with the byte write operation, once the stop
condition is received an internal write cycle will begin (see Figure 8).
Figure 6. Byte Write
6
INTEGRAL [ INTEGRAL CORP. ]
