9 pin SUB-D female socket to 9 pin SUB-D female socket.

A null modem cable connects to two standard serial ports for networking two computers together. Null modem cables enable direct data transfer with a minimum of setup required.

A null modem cable differs from ordinary serial cables the same way as Ethernet crossover cables differ from ordinary Ethernet cables. Null modem cables reverse the transmit and receive lines on end to enable direct two-way communication. A null modem cable for PCs ordinarily follows the RS-232 standard and uses the same serial ports as RS-232 cables.

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Pin layout:
DB9F - DB9F
6+1 - 4
2 - 3
3 - 2
4 - 6+1
5 - 5
7 - 8
8 - 7
SHELL - SHELL

This cable can be used to connect your PC to a Starview, HUMAX, Eurovox, Echostar receiver to carry out software updates.