Re: A92: Re: Shells and assembler
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Re: A92: Re: Shells and assembler
> > And what is Fargo? a program? I thought it was a kernel patch.
>
>Not as I understand it. The Fargo core is placed in the backup
>file. This backup file does not contain any parts of the ROM.
>This is only the RAM.
What Fargo does, if I remember correctly, is overwrite the vector tables
and similar references that the OS creates in the lower end of ROM upon
reset. You reset your calculator, it writes all the appropriate system
stuff into RAM (hence the System: xxK in the Mem screen). Then the Fargo
backup wraps around and writes over the lower end of memory, where this
stuff is stored. What it most likely modifies is the interrupt jump table
that the M68K uses at the base of RAM, as well as perhaps installing some
hooks to run machine language code. In a sense, Fargo is both a program
-and- a kernel patch, though it only patches the working RAM data of the
kernel, not the kernel itself. Think of it as a TSR. :-)
--Cliff Biffle
Optimist: This glass is half full.
Pessimist: This glass is half empty.
Cynic: They drank my water. Figures.
Engineer: The glass should be -half- this size! -Ender
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