About drivers in BIOS

At 01:25, Thursday July 02, 1998 there was such a thing that
Denis Dmitriev scribbled a letter from Roman Petrov:

DD>> By the way, will the drivers be in the main memory?
DD>> 8[ ] or
DD>> all the same on pages will they run away? :)
RP>> Well, you can do it by page, although I assumed in the main one. And
RP>> if you shove it across pages, then you’ll have to create extra system variables RP>
RP>> variables
DD>,
We’ll see, I’ll think about it.

DD> Well, as far as I think, this limit may well suit
DD> address 25000 (I don’t know who it is, but I place code
DD> almost everywhere from this address, and have not noticed any inconveniences yet).
Me too ;-)
DD> So in my opinion: it is better to sacrifice a few
DD> extra bytes in the main memory for system variables than a few kilobytes of the
DD> running memory itself for the driver...
B In principle, there are no problems with adding drivers to pages, or rather there are,
but one thing: on different machines there are a lot of pages and accordingly
there will be a lot of variables. So we get 2 possible solutions: either leave
the drivers in the main memory, or allocate only 1-2 pages for the drivers.
Who looks at this? You can select the first two pages of extended memory. Just then a little idea for the coders - if anyone wantsIf you use
these pages not for drivers, but for some of your own needs, then you can simply
change the value of the system variable indicating the lower limit of drivers
on the page. Do you think 16-32 kilobytes is enough for all the drivers?
Or maybe even 128 possible drivers is also overkill? Maybe 64 will be enough?
If it is enough, then the lower limit where you can load a program completely
painlessly drops to #5F00.

RP>> the main memory will be loaded only by the NeOS command interpreter itself, in programs you can install the RP
RP>> driver not
DD> through NeOS, but through the BIOS, then there are no RP> problems - at least place
DD> anywhere. this is understandable, you can get by with just trdos ;) It would be necessary,
But you won’t be able to do it entirely ;-) After all, a program can install a driver, but not remove it when it exits, so another program can use it as a
driver.
DD> so that all such things are managed by only one standard
Such things - what are they? I didn’t understand you a little.
DD> is a system unit - it will be more convenient for user programs, and
DD> the system will be quite easy to manage. In general, think about this
DD> option, maybe it will work out?
Well, I expressed my ideas, what do you say? I'm waiting for an answer, I won't change anything for now.

With respect, Roman aka Megus of Brainwave Association.

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