การต่อ RS232 แบบ Crossover or Null Modem เชื่อม Optimod

เก็บข้อมูลไว้ดู การต่อ RS232 แบบ Crossover or Null Modem  ใช้รีโมทเชื่อม Software กับ Optimod 8400

A Null Modem or “crossover” cable is used to connect to DTE devices together. For this to work, the Transmit (TxD) pin of one device needs to be connected to the Receive (RxD) pin of the other device, and vice versa.

To enable handshaking between the two devices, the Request to Send (RTS) pin of one device must be connected to the Clear to Send (CTS) pin of the other device, and the Data Set Ready (DSR) pin is connected to the Data Terminal Ready (DTR) pin of the other.

Null modem adapters can also be used at the end of a straight-through serial cable to cross the lines. The StarTech SCNM9FF is an example of a null modem cable.

ลักษณะหมายเลขประจำขาขั้วต่อ DB-9