AT88SC0404C-PI Atmel, AT88SC0404C-PI Datasheet - Page 45

• 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

Example 1
®
®
We assume Atmel
CryptoMemory
ATR contains the byte TA(1) = 15h, indicating that it is capable of using F=372 and
D=16, leading to a baud rate of 153,600-baud at 3.5712MHz. Assuming that this is the maximum speed supported by
the device, the reader immediately attempts to set the F and D parameters leading to these values.
• PPS_request= $FF $10 $15 $FA
• PPS_response = $FF $10 $15 $FA
The newly negotiated values are effective immediately following this exchange, so that the ETU, or duration of one bit
on I/O, will now be 23 clock cycles instead of 372.
Example 2
The reader insists on negotiating Fn and Dn equal to the default values, even though these would be used by default
without the use of a PPS exchange. The two ways of doing this are by sending PPS1_request = $11 or not sending
PPS1_request at all.
• PPS_request = $FF $10 $11 $FE
• PPS_response = $FF $10 $11 $FE
or
• PPS_request = $FF $00 $FF
• PPS_response = $FF $00 $FF
Example 3
The reader attempts to negotiate values that are not supported by the CryptoMemory device. In its response, the
CryptoMemory proposes to continue with F and D, by not sending PPS1_response. Even though new Fn and Dn
values aren’t negotiated, this scenario is still considered a “successful” exchange according to ISO 7816.
• PPS_request = $FF $10 $45 $AA
• PPS_response = $FF $00 $FF
Example 4
If the reader attempts to change the protocol to any protocol other than T = 0, such as T = 1, the CryptoMemory will
indicate that it only supports T = 0.
• PPS_request = $FF $01 $FE
• PPS_response = $FF $00 $FF
CryptoMemory will only operate at baud rates above the default 9600 baud through a successful PPS exchange.
CryptoMemory cannot be set to higher baud rates through use of a TA(2)-byte in the ATR.
Atmel AT88SC0104/0204/0404/0808/1616/3216/6416/12816/25616C
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5211C–SMIC–01/10