RS232 Colours

Feb 28, 2005 3 Replies
C

Good morning. It's nice to see the Milton fans are up and around during Lent.

Use this link and an ohmmeter to help you determine the relationship between DB-9 or DB-25 pins and their RS-232 function:

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Here's what they have to say (formatted in fixed font):

DB-9 Pin Corresponding DB-25 Pin Signal Function 2 3 RD Received data 3 2 TD Transmitted data 8 5 CTS Clear to send 7 4 RTS Request to send 6 6 DSR Data set ready 5 7 SG Signal ground 4 20 DTR Data terminal ready 1 8 DCD Data carrier detect

I wouldn't rely on wire insulation colors.

"[He] who overcomes lice By force hath overcome but half his foe; He must get the nits, too." ;-)

Chris

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R

There are no color standards for RS-232 wiring, you have to go by the pin position. For DB-9 connectors its

1 NC 2 RXD 3 TXD 4 DTR 5 GND 6 DSR 7 RTS 8 CTS 9 NC
Rich Webb Norfolk, VA
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P

Hi all,



I have a RS232 connector which only has 4 wires (ripped from an old mouse)



The wires have been colour and text labeled:



RT - White V - Blue RX - Orange G - Green



IIRC from a cable wiring guide, RT = pinout 3 (transmit) V = 7 (RTS) RX = 2 (Receive) and G = 5 (ground)



Have I got the pinouts right? The colour of the wires are a bit confusing.



Thanks



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W

He's correct, the wiring color code is not defined for RS232

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