X28HC256D-90 INTERSIL [Intersil Corporation], X28HC256D-90 Datasheet - Page 6

• Manufacturer Part Number: X28HC256D-90
• Description: 5V, Byte Alterable EEPROM
• Manufacturer: INTERSIL [Intersil Corporation]

DATA Polling I/O
FIGURE 3. DATA POLLING SOFTWARE FLOW
A
0
TO A
I/O
WE
CE
OE
SAVE LAST DATA
14
AND ADDRESS
7
COMPLETE?
WRITE DATA
READ LAST
COMPARE?
ADDRESS
X28HC256
WRITES
WRITE
READY
LAST
IO
7
V
An
IH
7
YES
YES
6
NO
An
NO
HIGH Z
FIGURE 2. DATA POLLING BUS SEQUENCE
An
V
OL
X28HC256
An
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.
An
An
An
V
X28HC256
READY
OH
May 7, 2007
FN8108.2