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Full Version: External Modem On Parallel Port
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I've got an external US Robotics Modem connected via the parallel printer port (although it is described as a serial modem).

I've looked for advice on this in the 'Modem HowTo' section, but can't work out how to get it to work. Is it possible to get the modem to work via this connection? Can I buy a serial port cable which will work instead?

Thanks for any help.
The short answer is no. You can not connect a serial modem directly to a parallel port. The signal levels are incompatable as well as the data protocol. There are RS-232 to parallel converters but the simplest solution if your computer does not have a serial port would be to purchase a USB serial port adapter. There are also PCMCIA serial port cards if your PC is so equiped. I've never used one but have seen posts where others have been able to get the USB adapters to work with linux.

Parallel and serial cables are wired differently. If there is a serial port on your PC then you will need to purchase a NULL modem serial cable. PCs have 9 pin connectors vs 25 pins on the modem.

There is lots of information on how serial (RS-232) and parallel ports work on the web. If you can't find anything then post back and I can provide additional help.
Thanks very much for your help. I'll get hold of a serial cable for it and try that.

Everything else on it works OK, so I'll be well pleased once I can connect to the web via Linux!
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