Re: emm386 in C?

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> From: Imre Leber <[email protected]>
> In one of the site i found were some very interesting tutorials by Alexei
A.
> 
>     http://members.tripod.com/protected_mode/alexfru/pmtuts.html
> ...
> This proves that you can write an emm386 almost completely in C, and i
think
> that is what we should do also. 

basically, you are right - it's certainly possible to write an EMM386 in
90 % C, and I agree 110%, that it's the better/easier way to do it.

however - regarding tut15 in particular, there are a couple of 
issues missing in tut15, that would be required in a real EMM386, like

nontrivial:
- running in PAGE mode (else no EMS/UMB)
- make it VCPI compliant (the reason, you aren't happy with existing
EMM386)

with some work:
- make ALL programs work (see differences between tut15 and tut16)

easy (??)
- map mouse interrupt as well (and all others)
- map some memory to upper memory (it's reason to exist)
- make it a TSR, then a DEVICE= driver
- move as much code/data to HIGH ( > 1.064 MB) memory as possible
- provide int15/87 handler
 

> and it does not even mean that it will be that more slower
> (look at the FreeDOS kernel).

As the monitor is 99,9% of the time only reflecting interrupts back to the
V86 task, you would probably write that in ASM completely - no great deal.

all the rest can (and should) be done in C, true.


now go ahead - and good luck.

tom