AT88SC0204CA-TU Atmel, AT88SC0204CA-TU Datasheet - Page 44

• Manufacturer Part Number: AT88SC0204CA-TU
• Manufacturer: Atmel

Specifications of AT88SC0204CA-TU

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Mounting: Surface Mount
• Pin Count: 8
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Compliant

10.
10.1. Character Format
10.2. Command format
8664C–CRYPT–01/10
Asynchronous T=0 Protocol
Atmel
shown in the following figure: note that the byte is transmitted with the least significant bit first.
Figure 29. Character Format
Even parity is used: the parity bit is such that the overall sum of bits in the data byte and the parity bit is an even
number. If a transmission error is detected, the receiving device indicates this by applying a low level on the I/O
channel during the guard time. This tells the transmitting device to retransmit the byte.
The command sequence is as follows:
1.
2.
3.
4.
Note:
I/O
A
Z
― INS is the instruction byte.
― P1 and P2 are reference bytes, such as a data byte address or password index.
― P3 is the number of data bytes transferred during the command. For outgoing transfers (e.g. read commands),
In compliance with ISO 7816-3, the host must send the header consisting of 5 characters: CLA, INS, P1, P2, P3
― CLA refers to a class of instructions. This byte isn't tested by the device.
The device replies with a "procedure byte” normally equal to the INS code received. If a problem occurred, then
the device will respond with a status word pair SW1-SW2, indicating the end of the command
Data transfer (P3-bytes).
A final SW1-SW2 sequence gives the status of the device after completion of the command. A normal completion
is indicated by SW1-SW2 = $90-$00
®
Start bit
CryptoMemory
P3 = 0 means that 256-data bytes will be emitted by the card. For incoming commands, P3 = 0 means that no
data bytes will be transferred.
For all bytes transmitted by the device or by the host, including header, procedure, status and data bytes, if a
parity error is detected, the receiver requests that byte to be sent again (see character format)
0
t
d
1
0
®
d
complies with the asynchronous T=0 protocol defined in ISO 7816-3. The character format is
1
(n ± 0,2) etu
d
2
8 data bits
d
3
d
4
d
Atmel AT88SC0104/0204/0404/0808/CA
5
d
6
t
d
n
7
Parity bit
p
t
Guard Time
10
Next Start bit
43