PDA

View Full Version : PCMCIA to Serial



4Lowie
18-11-2006, 09:19 PM
Hi all, whats a good PCMCIA to serial card? Are they any better than using a USB to serial converter?

Thanks

bob_doe_nz
18-11-2006, 10:27 PM
Put it this way, what do you need it for?
If say an old joystick for example and you already have a usb -> serial converter getting a PCMCIA converter really wont do much.

Graham L
19-11-2006, 02:47 PM
The PCMCIA and USB adapters both do the same thing. (The card one might cost more. ;))

However, there will be differences (in both sorts) in how complete the serial implementation is. :( Most hardware will work correctly for data transfer, but if the software for the hardware requires direct access to the status and control registers (often DOS programmes) that is sometimes a problem. (If you don't understand that, don't worry ... you almost certainly don't need it. :))

4Lowie
19-11-2006, 07:51 PM
Thanks, The software I'm using is Race Studio for Kart racing. This is an old program that downloads via IR through a serial port. I've been told that the USB converter creates a virtual com port which the software can't recognise. Also been told that the PCMCIA card connect dirrectly to the main bus and thus become the same as it was built that way from the start.

What do you think???

Thanks

developer
19-11-2006, 08:11 PM
One laptop at work has that card. It seems to be good, provides four serial ports. You only need to plug it in when you need those ports.

4Lowie
21-11-2006, 08:54 PM
Any thoughts about the virtual port idea?

Graham L
26-11-2006, 01:25 PM
This looks as if this is one of the cases where you do need to know about registers. :(

An IR adapter connected to a serial port doesn't use the port as a serial port. It uses bits in the status and control registers to drive and read opto devices.

I suspect the easiest approach might be to get hold of an older computer with a real serial port. :D

"Virtual ports" or any emulation of a serial port which does not have real registers won't work with that sort of device. The programmes will access the registers directly, using their hardware addresses. DOS programmers did that to get full control, especially for timing-dependent applications. From NT onwards, MS have tried to enforce the rule that user programmes should only access hardware through the OS. This can be emulated by USB adapters, but a programme which tries to access, e.g, bit 3 of register $3f9 will not work. :cool: