On Mon, 14 Dec 1998 19:56:22 +0800, you wrote:

>Hi all
>Does anyone know, or can point me in a good direction, on
>what pins of a pcmcia modem are the serial in/out, rts, cd, dtr etc?
>Thanks
>Justin
Sorry, but it's not quite that easy.  In the case of a 'generic'
PCMCIA modem, the PCMCIA port is a bus interface that looks like that
of a serial card of the type used in PCs. When you plug it into a PC,
the PCMCIA card gets mapped into I/O space at the normal serial port
address, so software can use it as if it were a conventional modem on
a normal serial port.
Within the card, there is also some memory which is used for card
identification & a little bit of address decoding, but most of this
can be ignored for your purpose. It wouldn't be too hard to interface
to - you'd need enough I/O for an 8 bit data bus & a few control lines
- most of the PCMCIA address lines could be tied high/low as required.
The official PCMCIA card spec tells you all you need to know, but it's
very expensive. An alternative is the book 'PCMCIA System
Architecture' (Addison Wesley ISBN 0-201-40991-7), which should cover
enough to interface to a modem card.
You'll also need data on programming the PC-style UART chips - try the
Nat. Semi. website.