I have weighbridge digitizer and it has two serial port like COM1 and COM2. one of the COM port is connected to customer PC and another one port is connected for another PC and distance is 10Mtr. Now second COM port is gets failure and its doesn't show any out puts in serial terminal.I have verified the output cable of weighbridge digitizer.in that, Pins 1,4,6 are shorted and Pin 7&8 is shorted .default 2-RX,3-TX,5 Gnd is connected in the male connector.I have extend the serial cable due to insufficient length .In that extension cable only RX-2,Tx-3,5-Gnd pin is connected and another end is same connected with PC2.

Now problem is COM2 in weighbridge digitizer was failure and when I am checking with serial to USB through tera term ,its doesn't show anything.

My question is,we need to short pin 1,4,6 and pin 7,8 or not.if its not connected it will affect the COM port?

 

hi mt,
Check this link for a RS232 null modem connection, with loop hand shaking connections.
Have you linked those hand shake pins at the PC Terminal connector.?

https://www.lammertbies.nl/comm/info/RS-232_null_modem.html

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one DB9 is have these hand shake pins connections.another end its doesnt have .It has only RX,TX,GND(1-4-6,7-8 not shorted).
is this will affect devices

 

hi mt,
If the PC/Terminal program is checking the hand shake lines, they must be connected and/or linked at both ends of the connecting cable connectors.
See image in post #2
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