AT88SC0204CA-SH ATMEL [ATMEL Corporation], AT88SC0204CA-SH Datasheet - Page 14

• Manufacturer Part Number: AT88SC0204CA-SH
• Description: Atmel CryptoMemory
• Manufacturer: ATMEL [ATMEL Corporation]

11.
11.1
Protocol Selection
The AT88SC0204CA supports two different communication protocols.
The power-up sequence determines establishes the communication protocol for use within that power cycle. Protocol selection
is allowed only during power-up.
Synchronous Two-wire Serial Interface
The synchronous mode is the default mode after power up. This is due to the presence of an internal pull-up on RST. For
embedded applications using CryptoMemory in standard plastic packages, this is the only available communication protocol.
Figure 11-1. Synchronous Two-wire Protocol
Note:
CLK-SCL
I/O-SDA
• Smartcard Applications:
• Embedded Applications:
•
•
•
Smartcard applications use ISO 7816-B protocol in asynchronous T = 0 mode for compatibility and interoperability with
industry standard smartcard readers.
A two-wire serial interface provides fast and efficient connectivity with other logic devices or microcontrollers.
RST
V cc
Power-up V
After stable V
Once synchronous mode has been selected, it is not possible to switch to asynchronous mode without first powering
off the device
Five clock pulses must be sent before the first command is issued
CC
CC
, RST goes high also
, SCL (CLK) and SDA(I/O) may be driven
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Atmel AT88SC0204CA [Summary DATASHEET]
5202FS−CRYPTO−12/11
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