WRITE Cycle

in Progress

AI01049

Next

Operation is

WRITE

START Condition

Byte Address

with RW = 0

ACK

Returned

YES

NO

YES

NO

ReSTART

STOP

Send

DATA BYTE

STOP

Figure 7. Write Cycle Polling using ACK

duced by an ACK polling sequence issued by the

master. The sequence is as follows:

– Initial condition: a Write is in progress (see Fig-

ure 7).

– Step 1: the Master issues a START condition

followed by a Device Select byte (1st byte of

the new instruction).

DEVICE OPERATION (cont’d)

– Step 2: if the memory is busy with the internal

write cycle, no ACK will be returned and the

master goes back to Step 1. If the memory

has terminated the internal write cycle, it will

respond with an ACK, indicating that the mem-

ory is ready to receive the second part of the

next instruction (the first byte of this instruc-

tion was already sent during Step 1).

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M2201