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VIA6522是一种可编程的多用途接口适配器,由超大规模集成电路组成,一片6522具有 A、B 两个8位并行输入输出端口(PIO),一个串行输入输出端口(SIO),两个内部计时/计数器 T_1和 T_2(CTC),两个时钟输入输出通道,4条状态控制线和联络线,另外还有一些控制线(R/W,(?),Φ_2等)及8条双向数据总线与 CPU 相连,片选择线(CS_1,(?))用于选通6522,PIO具有锁存功能,每个端口(PA口,PB口)各有8条并行输入/输出线与外围设备通信;SIO 串行输入/输出可用于数据串行传送或串/并变换,CTC 可用于连续计时(作实时时钟),一次(定时)计时或计外围设备送来的脉冲数等,两个 CTC 通道可根据需要作输出或输入;4条状态控制线和联络线可与外设联络作外部中断源。
The VIA6522 is a programmable multipurpose interface adapter consisting of very large scale integrated circuits. The 6522 has two 8-bit parallel input and output ports (PIOs) A and B, one serial input and output port (SIO), two internal Timer / counter T_1 and T_2 (CTC), two clock input / output channels, four status control lines and tie lines, and some control lines (R / W, Connected to the CPU, chip select line (CS_1, (?)) Is used for strobe 6522, PIO has a latch function, each port (PA port, PB port) each has eight parallel input / output lines and peripherals; SIO serial input / output can be used for data serial transmission or serial / parallel conversion, CTC can be used for continuous timekeeping (for real-time clock), a time (timing) or count the number of pulses sent by the peripheral device, etc., two CTC channels According to the need for output or input; 4 state control lines and contact lines can be peripherals to contact external interrupt sources.