🚀 go-pugleaf

2fttsubmit@kuhub.cc.ukans.edu writes:


>  I recently posted a question on how to access dos interrupts during
>a TSR keyboard routine.  Thanks to the help of the group I found out that DOS
>is not reentrant and some people suggested that I user the timer interrupt
>(1Ch) to poll a memory location the my keyboard driver sets and if that
>location is set then check the INDOS flags to see if they are clear and then
>use the interrupts.  
> ...
>  If someone could point me in the right direction it would be much
>appreciated.

This is not a trivial problem to solve. The best example of a solution that
I've seen is in the TSR sample code that comes with the Microsoft v6.0 
assembler. There was a Microsoft Journal article on the subject about a year
ago that had some good explanations, and included a pretty complete skeleton.
However, the code had several bugs in it! I've found two, but know from
other programmers that there are more lurking.

If you have access to a good bookstore, check Al Williams' book
"DOS5: A developer's guide". I think that it has quite some discussion on
TSR programming, and has been recommended by many.

George
-- 
George Pontis ( geo@netcom.COM )