X28HC64 Datasheet, PDF (4/24 Pages) Xicor Inc. – 5 Volt, Byte Alterable E2PROM

X28HC64
DATA POLLING I/O₇
Figure 2. DATA Polling Bus Sequence
LAST
WE ^WRITE
CE
OE
VIH
I/O7
HIGH Z
VOL
A0–A12
An
An
An
An
An
VOH
X28HC64
READY
An
An
3857 FHD F12
Figure 3. DATA Polling Software Flow
WRITE DATA
DATA Polling can effectively reduce the time for writing
to the X28HC64. 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.
WRITES
NO
COMPLETE?
YES
SAVE LAST DATA
AND ADDRESS
READ LAST
ADDRESS
IO7
NO
COMPARE?
YES
READY
3857 FHD F13
4