M24M02-DWMN3TP datasheet(15/38 Pages) STMICROELECTRONICS

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M24M02-A125

Instructions

4.1

Write operations

For a Write operation, the bus master sends a Start condition followed by a device select

code with the R/W bit reset to 0. The device acknowledges this, as shown in Figure 5, and

waits for the master to send two address bytes (most significant address byte sent first,

followed by the least significant address byte (Table 3). The device responds to each

address byte with an acknowledge bit, and then waits for the data byte.

The 256 Kbyte (2 Mb) are addressed with 18 address bits, the 16 lower address bits being

defined by the two address bytes and the most significant address bits (A17, A16) being

included in the Device Select code (see Table 2).

When the bus master generates a Stop condition immediately after a data byte Ack bit (in

the “10th bit” time slot), either at the end of a Byte Write or a Page Write, the internal Write

cycle tW is then triggered. A Stop condition at any other time slot does not trigger the internal

Write cycle.

During the internal Write cycle, Serial Data (SDA) is disabled internally, and the device does

not respond to any requests.

After the successful completion of an internal Write cycle (tW), the device internal address

counter is automatically incremented to point to the next byte after the last modified byte.

If the Write Control input (WC) is driven High, the Write instruction is not executed and the

accompanying data bytes are not acknowledged, as shown in Figure 6.

M24M02-DWMN3TP Datasheet(PDF) 15 Page - STMicroelectronics