X28HC256_07 Datasheet, PDF (6/20 Pages) Intersil Corporation – 5V, Byte Alterable EEPROM

DATA Polling I/O₇
LAST
WE ^WRITE
X28HC256
CE
OE
V_IH
I/O₇
A₀ TO A₁₄
An
HIGH Z
V_OL
An
An
An
An
An
FIGURE 2. DATA POLLING BUS SEQUENCE
V_OH
X28HC256
READY
An
WRITE DATA
DATA Polling can effectively halve the time for writing to the
X28HC256. The timing diagram in Figure 2 illustrates 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
X28HC256
READY
FIGURE 3. DATA POLLING SOFTWARE FLOW
6
FN8108.2
May 7, 2007