CAT25080, CAT25160
Byte Write
Page Write
Once the WEL bit is set, the user may execute a write
sequence, by sending a WRITE instruction, a 16-bit
address and data as shown in Figure 4. Only 10
significant address bits are used by the CAT25080 and
11 by the CAT25160. The rest are don’t care bits, as
shown in Table 5. Internal programming will start after
After sending the first data byte to the CAT25080/160,
the host may continue sending data, up to a total of 32
bytes, according to timing shown in Figure 5. After each
data byte, the lower order address bits are automatically
incremented, while the higher order address bits (page
address) remain unchanged. If during this process the
end of page is exceeded, then loading will “roll over” to
the first byte in the page, thus possibly overwriting
previoualy loaded data. Following completion of the
write cycle, the CAT25080/160 is automatically returned
to the write disable state.
¯¯
the low to high CS transition. During an internal write
cycle, all commands, except for RDSR (Read Status
¯¯¯¯
Register) will be ignored. The RDY bit will indicate if the
¯¯¯¯
internal write cycle is in progress (RDY high), or the the
¯¯¯¯
device is ready to accept commands (RDY low).
Table 5. Byte Address
Device
Address Significant Bits
A9 - A0
Address Don't Care Bits
A15 - A10
# Address Clock Pulse
CAT25080
CAT25160
16
16
A10 - A0
A15 - A11
Figure 4. Byte WRITE Timing
CS
0
1
2
3
4
5
6
7
8
21 22 23 24 25 26 27 28 29 30 31
SCK
SI
OPCODE
BYTE ADDRESS*
DATA IN
A
A
0
D7 D6 D5 D4 D3 D2 D1 D0
0
0
0
0
0
0
1
0
N
HIGH IMPEDANCE
SO
* Please check the Byte Address Table (Table 5)
Note: Dashed Line = mode (1, 1) - - - - - -
Figure 5. Page WRITE Timing
CS
24+(N-1)x8-1..24+(N-1)x8 24+Nx8-1
0
1
2
3
4
5
6
7
8
21 22 23
32-39
24-31
SCK
SI
DATA IN
Data Data
Byte 2 Byte 3
BYTE ADDRESS*
OPCODE
Data
Data Byte N
0
0
0
0
0
0
1
0
A
A
0
0
Byte 1
N
7..1
HIGH IMPEDANCE
SO
*Please check the Byte Address Table. (Table 5)
Note: Dashed Line = mode (1, 1) - - - - - -
© 2006 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
7
Doc. No. 1122 Rev. A