Write Data
Writes
No
Complete?
Yes
Save Last Data
and Address
X28C010
DATA Polling can effectively halve the time for writing to the
X28C010. 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.
Read Last
Address
IO7
No
Compare?
Yes
X28C010
Ready
FIGURE 3. DATA POLLING SOFTWARE FLOW
The Toggle Bit I/O6
Last
WE Write
CE
OE
I/O6
VOH
*
VOL
HIGH Z
*
* Beginning and ending state of I/O6 will vary
FIGURE 4. TOGGLE BIT BUS SEQUENCE
X28C010
Ready
5
FN8105.0
May 11, 2005