Re: Device driver in Ada95

[Dave Poirier <instinc@users.sf.net>]

Jerry van Dijk wrote:
> Dave Poirier <instinc@users.sf.net> writes:
> 
> 
>>My next step is to start to write device drivers in Ada95 using this same
>>setup, so as to have as useable os sooner or later.  As my first try, I
>>decided to create a small vga driver for text mode.  This requires that I
>>write in memory from 0xB8000 to 0xB8A9F.
>>
> 
> This is not very difficult to do. However, GNAT generated x86 code depends
> on the memory management used. So the question here is: are you using
> real-mode, or DPMI, or some other PMODE driver for your own kernel ? Or
> if you use your own scheme, how is the memory organised ?

To make things simpler at the moment I use a flat memory model in 
protected mode, so I have 1 code segment of 4GB starting at 0 
read/execute with a 4GB data segment start at 0 read/write.

It's my own scheme.

btw, thanks to chris.danx, I couldn't find any code on the original 
AdaOS site, the link you provided was indeed usefull. (maybe you should 
consider using an array of pointers and a loop instead of repeating 255 
times the same code sequence) ;)

also thanks to sk for the small code snippet, was right to the point. 
Where can I find information about QUAD?  I've done a search for "Ada95 
QUAD" on google but nothing related to 'Access came up.

Thanks again :)