产品说明:
PCL-740
RS-232/422/485/电流环串行通讯卡
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RS-232, RS-422, RS-485或电流环接口
带16字节FIFO的16C550 UART
传输速率可达115 Kbps
灵活的I/O地址及IRQ选择
IRQ: 3, 4, 5, 6, 7, 9, 10, 11, 12 或15