AT88SC0204C-MP Просмотр технического описания (PDF) - Atmel Corporation

Номер в каталоге

Компоненты Описание

производитель

AT88SC0204C-MP

CryptoMemory® 2 Kbit

Atmel Corporation 

AT88SC0204C

Protocol Selection

Asynchronous

T = 0 Protocol

Synchronous

2-wire Serial Interface

The AT88SC0204C supports two different communication protocols.

• Smart Card Applications: The asynchronous T = 0 protocol defined by ISO 7816-3

is used for compatibility with the industry’s standard smart card readers.

• Embedded Applications: A 2-wire serial interface is used for fast and efficient

communication with logic or controllers.

The power-up sequence determines which of the two communication protocols will be

used.

This power-up sequence complies with ISO 7816-3 for a cold reset in smart card

applications.

• VCC goes high; RST, I/O-SDA and CLK-SCL are low.

• Set I/O-SDA in receive mode.

• Provide a clock signal to CLK-SCL.

• RST goes high after 400 clock cycles.

The device will respond with a 64-bit ATR code, including historical bytes to indicate the

memory density within the CryptoMemory family. Once the asynchronous mode has

been selected, it is not possible to switch to the synchronous mode without powering off

the device.

Figure 2. Asynchronous T = 0 Protocol (Gemplus Patent)

Vcc

I/O-SDA

ATR

RST

CLK-SCL

The synchronous mode is the default after powering up VCC due to the internal pull-up

on RST. For embedded applications using CryptoMemory in standard plastic packages,

this is the only communication protocol.

• Power-up VCC, RST goes high also.

• After stable VCC, CLK-SCL and I/O-SDA may be driven.

Figure 3. Synchronous 2-wire Protocol

Vcc

I/O-SDA

RST

CLK-SCL

1 2345

Note: Five clock pulses must be sent before the first command is issued.

5

2022ES–SMEM–07/04

Share Link: