tp170a与fx1s的通信电缆图
hmi设备 fx1s PLC
3(TXD+) ---------------------------------------------------2(RXD+)
8(TXD-) ----------------------------------------------------1(RXD-)
5(GND) ----------------------------------------------------3(GND)
4(RXD+) ---------------------------------------------------7(TXD+)
9(RXD-) ----------------------------------------------------4(TXD- )