db9 female-male?

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gastonanthony

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problem with the programmer i built a few days ago, the schematic used a db9 male as the connector, but my PC doesn't have a female slot for that connector, it only has a db9 male slot, so i used a female connector for the programmer for it. i just discovered a while ago that the db9 male and db9 female have different pinouts!how do i know which pin gives TX, RX, CTS, DTR, RTS, and GND?
this is how the db9 male and female terminals are labelled:

male: _ female:
5 4 3 2 1 _ 1 2 3 4 5
_9 8 7 6 ___6 7 8 9

Which pins should i switch?
 
If you look at the pinouts you provided.

male: _ female:
5 4 3 2 1 _ 1 2 3 4 5
_9 8 7 6 ___6 7 8 9

This is looking at the back of the connectors. If you bend the above diagram in half, about the middle, then pin 1 will coincide with pin 1, 2 with 2 etc.

So, don't swap any pins.

Pin 2 will always be out from your circuit and into the PC.
Pin 3 will always be out from the PC and into your circuit.

Which one of these is referred to as TX or RX is dependent on which device you are talking about - your circuit or the PC.

So,
Pin 2 is TX on your circuit and RX on the PC.
Pin 3 is RX on your circuit and TX on the PC.

HTH

Mike.
 
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