DocID11090 Rev 4 13/26
M34F04 Device operation
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3.8 Page write
The Page Write mode allows up to 16 bytes to be written in a single Write cycle, provided
that they are all located in the same page in the memory: that is, the most significant
memory address bits are the same. If more bytes are sent than will fit up to the end of the
page, a condition known as ‘roll-over’ occurs. This should be avoided, as data starts to
become overwritten in an implementation dependent way.
The bus master sends from 1 to 16 bytes of data, each of which is acknowledged by the
device if Write Control (WC
) is Low. If the addressed location is Write-protected, by Write
Control (WC
) being driven High (during the period from the Start condition until the end of
the address byte), the device replies to the data bytes with NoAck, as shown in Figure 4,
and the locations are not modified. After each byte is transferred, the internal byte address
counter (the 4 least significant address bits only) is incremented. The transfer is terminated
by the bus master generating a Stop condition.
Figure 5. Write mode sequences with WC
=0 (data write enabled)
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