cat93c5612 Catalyst Semiconductor, cat93c5612 Datasheet - Page 7

• Manufacturer Part Number: cat93c5612
• Description: Supervisory Circuits With Microwire Serial Cmos E2prom, Precision Reset Controller Watchdog Timer
• Manufacturer: Catalyst Semiconductor

Read
Upon receiving a READ command and an address
(clocked into the DI pin), the DO pin of the CAT93CXXXX
will come out of the high impedance state and, after
sending an initial dummy zero bit, will begin shifting out
the data addressed (MSB first). The output data bits will
toggle on the rising edge of the SK clock and are stable
after the specified time delay (t
For the 93CXXXX, after the initial data word has been
shifted out and CS remains asserted with the SK clock
continuing to toggle, the device will automatically incre-
ment to the next address and shift out the next data word
in a sequential READ mode. As long as CS is continu-
ously asserted and SK continues to toggle, the device
will keep incrementing to the next address automatically
until it reaches to the end of the address space, then
loops back to address 0. In the sequential READ mode,
only the initial data word is preceeded by a dummy zero
bit. All subsequent data words will follow without a
dummy zero bit.
Figure 2. Sychronous Data Timing
Figure 3. Read Instruction Timing
DO
CS
SK
DI
DO
SK
CS
DI
1
1
t CSS
1
1
1
0
HIGH-Z
VALID
PD0
A N
1
t DIS
or t
A N–1
PD1
1
t SKHI
)
1
Dummy 0
1
t DIS
A 0
9-91
t SKLOW
1
Write
After receiving a WRITE command, address and the
data, the CS (Chip Select) pin must be deselected for a
minimum of t
self clocking clear and data store cycle of the memory
location specified in the instruction. The clocking of the
SK pin is not necessary after the device has entered the
self clocking mode. The ready/busy status of the
CAT93CXXXX can be determined by selecting the de-
vice and polling the DO pin. Since this device features
Auto-Clear before write, it is NOT necessary to erase a
memory location before it is written into.
Page Write
The 93CXXXX writes up to 16 bytes (8 words for x16
format) of data in a single write cycle, using the page
write operation. The page write operation is initiated in
the same manner as the byte (word for x16 format) write
operation. However, instead of terminating after the
initial byte (word for x16 format) is transmitted, the host
1
D 15 . . . D 0
or
D 7 . . . D 0
VALID
1
1
Address + 1
D 15 . . . D 0
or
D 7 . . . D 0
CSMIN
t DIH
t PD0, t PD1
1
Don't Care
DATA VALID
. The falling edge of CS will start the
1
Address + 2
D 15 . . . D 0
or
D 7 . . . D 0
1
t CSH
1
Address + n
D 15 . . .
or
D 7 . . .
t CSMIN
CAT93CXXXX
Stock No. 21084-01 2/98