lec12_smartcards0

lec12_smartcards0 - Lecture 12: Smartcards Memory cards -...

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Lecture 12: Smartcards Memory cards - simple type of smartcard. Memory cards only have some amount of memory inside the card and this memory can be normally read and written. There is normally nothing really intelligent inside those cards. Typically the memory inside this kind of card is EPROM, EEPROM or FLASH memory. This card type is very widely used as a telehone card (telecards). Many countries use a telecard system which is very close to the first smartcard telephone system in use in France. Real smartcards - have real microprocessor inside the card. There have been many different small microprocessors used inside smartcards including 8031/51 variants, PIC microcontrollers and some special microprocessors just designed for smartcard applications. Very many smartcards communicate using the protocols standardized in the ISO 7816 standard which defines many physical features, including card size, mechanical strength and electrical properties. The standard pinout is: C1: Vcc = 5V C2: Reset C3: Clock C4: API C5: Gnd C6: Vpp C7: I/O data C8: API Pins marked with API are application specific pins defined in application standards. The standard supports two transmission modes: Asynchronous transmission: In this type of transmission, characters are transmitted on the I/O line in an asynchronous half duplex mode (transmission allowed in either direction, but only 1 at a time, whereas full duplex allows simultaneous transmission both ways). Each character includes an 8 bit byte. Both devices have independent and separate clocks. Synchronous transmission: In this type of transmission, a series of bits is transmitted on the I/O line in half duplex mode in synchronization with the clock signal on CLK. Both devices therefore share the same clock. Exercise: What are advantages/disadvantages to sync vs async communication, in terms of thruput, error parity, cable needs, driver overhead, and dependency. There is a selection of different protocols available for communicating with the card. There is a method for selecting which communication protocol to use (one card can support one or more protocols). The most commonly used protocol seems to be asynchronous half duplex character transmission protocol. Reading the data is from a serial EEPROM over a two-wire (I2 C) or three-wire SPI or microwire bus; the power, clock, and data lines are connected separately. Some wired smartcards use RS-232 type asynchronous communications, and in this case they supply power and communication through different wires.
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Lecture 12: Smartcards (cont) Contactless smartcards:
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This note was uploaded on 04/07/2010 for the course ELEC ecse 421 taught by Professor Guss during the Winter '10 term at McGill.

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lec12_smartcards0 - Lecture 12: Smartcards Memory cards -...

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