CAT28C256 CATALYST [Catalyst Semiconductor], CAT28C256 Datasheet - Page 8

• Manufacturer Part Number: CAT28C256
• Description: 32K-Bit Parallel E2PROM
• Manufacturer: CATALYST [Catalyst Semiconductor]

CAT28C256
DATA Polling
DATA polling is provided to indicate the completion of
write cycle. Once a byte write or page write cycle is
initiated, attempting to read the last byte written will
output the complement of that data on I/O
are indeterminate) until the programming cycle is com-
plete. Upon completion of the self-timed write cycle, all
I/O’s will output true data during a read cycle.
Figure 7. DATA Polling
Figure 8. Toggle Bit
Note:
(1)
Doc. No. 25020-0A 2/98
ADDRESS
Beginning and ending state of I/O
I/O 6
WE
OE
CE
I/O 7
WE
CE
OE
t OEH
D IN = X
6
is indeterminate.
(1)
7
t OE
t OEH
(I/O
0
–I/O
6
D OUT = X
8
t OE
t WC
Toggle Bit
In addition to the DATA Polling feature of the CAT28C256,
the device offers an additional method for determining
the completion of a write cycle. While a write cycle is in
progress, reading data from the device will result in I/O
toggling between one and zero. However, once the write
is complete, I/O
read from the device.
t WC
6
stops toggling and valid data can be
D OUT = X
(1)
t OES
t OES
28C256 F10
28C256 F11
6