X28HC64DI-12 INTERSIL [Intersil Corporation], X28HC64DI-12 Datasheet - Page 5

• Manufacturer Part Number: X28HC64DI-12
• Description: 5 Volt, Byte Alterable EEPROM
• Manufacturer: INTERSIL [Intersil Corporation]

THE TOGGLE BIT I/O
Figure 4. Toggle Bit Bus Sequence
Figure 5. Toggle Bit Software Flow
I/O
WE
OE
CE
6
* Beginning and ending state of I/O
Write
Last
From Addr N
Load Accum
Accum with
Last Write
Compare
Compare
Ready
Addr N
Ok?
Yes
Yes
6
5
*
No
V
OH
6
will vary.
V
OL
X28HC64
HIGH Z
The Toggle Bit can eliminate the chore of saving and
fetching the last address and data in order to implement
DATA Polling. This can be especially helpful in an array
comprised of multiple X28HC64 memories that is fre-
quently updated. Toggle Bit Polling can also provide a
method for status checking in multiprocessor applica-
tions. The timing diagram in Figure 4 illustrates the
sequence of events on the bus. The software flow dia-
gram in Figure 5 illustrates a method for polling the
Toggle Bit.
*
X28HC64
Ready
June 1, 2005
FN8109.0