AT88SC0104CA_11 ATMEL [ATMEL Corporation], AT88SC0104CA_11 Datasheet - Page 55

• Manufacturer Part Number: AT88SC0104CA_11
• Description: Atmel CryptoMemory Specification Datasheet
• Manufacturer: ATMEL [ATMEL Corporation]

10.10 Verify Password: $BA
10.10.1 Functional
Figure 10-7. Verify Password Command Functional Description
Read password indices: $10 to $17 for passwords 0, 1, 2, and 7.
Write password indices: $00 to $07 for passwords 0, 1, 2, and 7.
Secure code index: $07 (equivalent to Write Password 7).
Four password index bits "r" and "ppp" indicate the password to compare:
Table 10-14. Verify Password Command Structure
If the maximum number of trials has been exceeded, the device will return $69 $00 instead of the INS code, after receiving the
header, to indicate the command is unauthorized. The device increments the associated attempts count before verifying the
password, to prevent attacks. If the password is correct, the device memorizes this success, clears the attempts count and
returns $90 $00. If the password is wrong, the device simply returns $69 $00 after incrementing the attempts count. The Write
7 password is also known as the secure code and must be properly presented before access to the configuration zone is
granted when personalizing the device.
3 password bytes
CLA
**
r = 0: Write password,
r = 1: Read password,
p
2
p
1
p
0
: Password set number
INS : Command
$BA
Command Structure
Host
Command
Password Index
PW1
PW2
PW3
000r 0p
P1
2
p
1
p
0
Device
Atmel AT88SC0104CA/0204CA/0404CA/0808CA [Datasheet]
P2
**
$30
P3
d
7
--- ---d
PW1
0
Data Sent
d
15
PW2
--- ---d
8664E−CRYPTO−12/11
8
d
23
PW3
--- ---d
16
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