Re: A85: Features for a new shell
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Re: A85: Features for a new shell
No offense, but multitasking on the 85 is a stupid idea.
It would be way,way,way better to do on the 83+,86,89,or 92(+).
Cavan Carroll
PS I won't reply to your reply but the other people on the list might tell
you why I'm saying this.
> I will try to add support for BASIC programs to my shell, but for
>Usgard
>and ZShell I think I'd rather not to do so. It will increase the size of
>the
>shell, and anyway, only programs written for the new shell can be run in
>multitasking mode. But the relocation will be the same as Usgard.
>Concerning
>libraries, I will first put a lot of functions in the shell itself to make
>programing easier. After that, maybe ...
>
> I have some questions about the way the shell should handle
>multitasking.
>But first, a little description of the system...
>
>There will be 2 kinds of programs: real mode and protected mode. Programs
>for
>the real mode will run like in other shells, and programs for protected
>mode
>will run in multitasking mode. Obviously, there is restrictions to
>protected
>mode:
>
> - Programs can't use areas of memory like GRAPH_MEM or TEXT_MEM, so
>the
>shell create a safe area and return a pointer for each program.
>
> - When the user switch between the different programs running, the
>program which is given focus must update the screen.
>
>I have imagined 2 solutions to this last problem. The first consists of
>saving the whole screen for each program (bad idea for a 28 Kb RAM), and
>the
>second would be creating a function in each program to redraw the screen
>when
>the OS call it.
>
>If you have a better solution or if you know other problems implied by
>multitasking, please report it. I'm waiting for your feedback...
>
>Farid Bouzaghti
>
>
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