How to make a 4 wire phone crossover cable

Using a cat5 cable, terminating with rj11, what is the pin-out for each end of the rj11?
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Rob WilliamsConnect With a Mentor Commented:
That's a tough one. There are dozens of serial/RS-232 configurations however, a typical phone extension crossover is as simple as:
RJ-11 #1        RJ-11 #2
   pin 1    =>     pin 4
   pin 2    =>     pin 3
   pin 3    =>     pin 2
   pin 4    =>     pin 1

However, please do not accept this as correct for your purposes. You should verify with your supplier first, as the internal wiring of the serial adapter can be all sorts of configurations.
b0lsc0ttIT ManagerCommented:

I'm not exactly sure I understand what you are looking for but I am pretty sure it is in the diagram at .

Let me know if you have any questions or need more information.

smcintire001Author Commented:

no that does not help or answer my question
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Rob WilliamsCommented:
If this is for phone why does it need to be a cross-over.
If it is for network you cannot do so with an RJ-11, it must be an RJ-45:
smcintire001Author Commented:
i need to hook up a device to a computer.

i got a serial to rj11 converter on both device's com1 ports.  but i ran a cat5 cable, not knowing that they sent me serial to rj11.  SO... i need to know what pinout to use so that these 2 devices talk.

this is what they told me:  "The connection between your computer and the controller is a four wire phone cable that does a crossover.  but you can use the cat5 to transmit. "
Rob WilliamsCommented:
Thanks smcintire001.
Cheers !
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