🚀 go-pugleaf

Hi,

I am trying to write a driver for a device which accepts commands thru
the parallel port. I have used INT17 for that, and the thing works.
The way I've done it is simple - I am checking bit 7 after getting a
status info of the LPT port via INT17. When bit 7 is NOT_BUSY I send a
new character down the line.

I know that there is also a way to access the LPT port directly thru the
in/out commands and its 3 I/O registers. Are there any advantages (in
terms of speed) in using interrupt driven parralel I/O, as compared to
INT17 BIOS service as I have used it - if there is, how much, and is
it doable in C?? I can just about read assembler, but that's about it.

The speed of the application is crucial - I need to send as many bytes
thru the LPT port as possible (order of 1e6). N.B. does anyone know the
approximate number of bytes per second that can be sent thru the LPT port
via INT17 and/or interrupt driven parallel I/O??

Any suggestions, pointers, code snippets, anything, will be of immense value.
Thanx in advance.

--Nino

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