null modem

(redirected from Null-modem cable)

null modem

(communications, hardware)
A cable, especially an EIA-232 cable, for connecting serial ports on two computers directly, rather than via modems. Since, according to the specification, both computers should transmit on pin three of their EIA-232 connectors and receive on pin two, a null modem cable needs to connect one computer's pin two to the other's pin three and vice versa. It also needs to have male connectors at both ends (again, according to the specification).
References in periodicals archive ?
The FSM726S includes everything needed to stack and/or rack-mount the switch: a stacking cable, the hardware for installation in a 19-inch rack, as well as a null-modem cable and NETGEAR's 5-year warranty.
Wireless service providers can view these HTML pages through a direct serial connection between a laptop and the ICU using a null-modem cable.
These functions take advantage of wireless infrared connectivity, hard wire connections using serial and parallel null-modem cables or even remote modem connectivity.