X28HC256 Datasheet, PDF (4/24 Pages) Xicor Inc. – 5 Volt, Byte Alterable E2PROM

X28HC256
DATA POLLING I/O₇
Figure 2. DATA Polling Bus Sequence
LAST
WE ^WRITE
CE
OE
VIH
I/O7
HIGH Z
VOL
A0–A14
An
An
An
An
An
VOH
X28HC256
READY
An
An
3859 FHD F12
Figure 3. DATA Polling Software Flow
WRITE DATA
WRITES
NO
COMPLETE?
YES
SAVE LAST DATA
AND ADDRESS
DATA Polling can effectively halve the time for writing to
the X28HC256. The timing diagram in Figure 2 illus-
trates the sequence of events on the bus. The software
flow diagram in Figure 3 illustrates one method of
implementing the routine.
READ LAST
ADDRESS
IO7
NO
COMPARE?
YES
X28HC256
READY
3859 FHD F13
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