AT91系列微处理器和智能卡的接口Software ISO 7816 I/O Line Implementation Features ISO 7816-3 compliant (direct convention) Byte reception and transmission with parity check Retransmission on error detection Automatic reception at the end of transmission Dynamically programmable baud rate (PTS) ARM Procedure Call Standard (APCS) compliant AT91 ARM Thumb Microcontrollers Application Note Introduction ISO 7816-3 is the standard for electronic signals and transmission protocols for IC cards with contacts. It defines the characteristics of the signals used to communicate with a Smart Card including the I/O line which allows messages to be exchanged. The AT91M40400 does not have dedicated hardware to manage the ISO 7816 I/O line, but because of the high processing speed and flexible Timer Counter (TC), an effective so……