AT88SC0404C-PI Atmel, AT88SC0404C-PI Datasheet - Page 52

• Manufacturer Part Number: AT88SC0404C-PI
• Manufacturer: Atmel

Specifications of AT88SC0404C-PI

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Package Type: PDIP
• Mounting: Through Hole
• Pin Count: 8
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Not Compliant

9.4.6. Send Checksum
5211C–SMIC–01/10
Atmel AT88SC0104/0204/0404/0808/1616/3216/6416/12816/25616C
Write Config Zone
The maximum number of bytes that may be written is as follows:
• $10 for Atmel
• $40 for Atmel AT88SC3216C and Atmel AT88SC6416C (EEPROM page size of 64-bytes)
• $80 for Atmel AT88SC12816C and Atmel AT88SC25616C (EEPROM page size of 128-bytes)
Each data byte within a page must only be loaded once. In anti-tearing mode the maximum value for N is $08 for all
devices.
If the address provided at P2 is an unauthorized address, the device will return the "Command Unauthorized" code
($69 $00) after it has received the header. Since access rights vary throughout the configuration memory, the host may
provide an authorized starting address, but a number of bytes that causes the device to reach unauthorized address. In
this case, the device will prevent the internal write cycle and no bytes will be written in the EEPROM. At the end of the
command the "Command Unauthorized" code ($69 $00) will be returned instead of $90 $00 to indicate that no write
cycle occurred.
Write Fuses
The fuses may only be "programmed", that is written from '1' to '0'. The write fuses operation is only allowed after
successfully presenting the secure code (Write 7 Password). The fuses must be blown sequentially: FAB must be
blown first, CMA may be blown only if FAB is ‘0’, and PER only if CMA is ‘0’.
Table 40. Fuse Writing
To write data to user zones that require Authentication for write access (AM [1:0] = “01” or “00” in the access register),
the host should first carry out the Write User Zone command $B0, after which the device will return a special status
word: $62 $00. This indicates that the memory is unchanged and the device is waiting for the host to provide a valid
checksum before initiating the write cycle. The host sends the checksum it has computed using the System WRITE
command opcode $B4 with P1 = $02. Only if the checksum is valid will the device initiate the write cycle. Furthermore,
if the device receives an incorrect checksum, it will clear the authentication privilege.
Set User Zone
Before reading and writing data in the user zones, the host should select a zone with this command. At this time the
host may choose whether anti-tearing should be active for this zone.
Table 41. System WRITE
CLA
**
Fuse
CMA
FAB
PER
INS : Command
®
AT88SC0104C through Atmel AT88SC1616C (EEPROM page size of 16-bytes)
$B4
Fuse ID
$06
$04
$00
p
User Read
7
P1
--- p
0
p
7
P2
--- p
0
n
7
P3
--- n
0
d
Data(1)
7
--- ---d
Data Returned
0
...
...
d
Data(N)
7
--- ---d
51
0