at88sc1608 ATMEL Corporation, at88sc1608 Datasheet - Page 11

• Manufacturer Part Number: at88sc1608
• Description: 8 X 256 X 8 Secure Memory With Authentication
• Manufacturer: ATMEL Corporation

Write Fuses
0971G–SMEM–04/04
The read fuses operation is always allowed. The device only transmits one data byte
and waits for a new command.
Figure 8. Write Fuses
The write fuses operation is only allowed under secure code control and no data byte is
transmitted by the host. The fuses are blown sequentially: CMA is blown if FAB is equal
to “0”, and PER is blown if CMA is equal to “0”. If the fuses are all “0”s, the operation is
canceled and the device waits for a new command.
Once a stop condition is issued to indicate the end of the host’s write operation, the
device initiates the internal nonvolatile write cycle. An ACK polling sequence can be ini-
tiated immediately. Once blown, these fuses cannot be reset.
S
T
A
R
T
1 0 1 1 0 1 0 0
Command
A
C
K
1 0 0 0 0 0 0 0
Fuses Add
AT88SC1608
A
C
K
S
T
O
P
11