How catching a barcode device !!

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Guest

Hi , I'm finishing a new project and a new request is to catch a Ps2,
simulated keyboard, barcode device. My application is a console application
without forms or others kind of user interface. Also I have a serial
communication in a thread with a several priority, a ftp server always in
listening status and is possible to run a tool to communicate by second
serial. Alls is concentrate inside a 486 100MHz and 32Mbyte of RAM.
Using 'GetAsyncKeyStatus' I have some problem because I loose sometime key
status if I use a normal thread priority, if I increase the priority I loose
lot of time in the serial communication.
Someone has some tips for me or is prefer to use other kinds of device,
serial for example ?? thank you very much, fabbrit
 
Huh? It sounds to me like you've chosen very poorly in how you connect
things. Trying to use GetAsyncKeyStatus() is a *hopeless* way to try to
catch every key as it arrives. It seems like you should have chosen a
different way to connect the barcode scanner, so that you could control the
communication with it (serial comes to mind).

However, since you're probably stuck with what you have, use a low-level
keyboard hook to trap all keyboard events in the system (you'll have to do
this in native code, I think). For each keypress, you can then do whatever
you need to do, drop the key in a queue for serial transmission or whatever.

Paul T.
 
Did the manufacturer of the device you're using provide a library for using
their device? Normally that's the best mechanism available.

David
 
Hi Paul, Hi David,

thanks for your help and interesting.

to Paul: I'll try to use yours tips and the documents that you got me the
coordinates, thank you very much.
I'll send you some news in a few days

to David: tha barcode device is a very normal PS2 keyboard that simulate
keyboard inlet. No docs;

bye, fabbrit
 
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