Re: Re : Re: A92: Fargo relocation process


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Re: Re : Re: A92: Fargo relocation process





On Tue, 12 Aug 1997 Hmlacage@aol.com wrote:

> You mean that fargo relocates the p^rogram in a memory area where the OS
> cannot relocate it ? So that when executing the program, the program is not
> relocated ? 

I'm not really sure what you are talking about. The OS never
relocates anything because the OS only handles variables & text -
data not containg machinecode to be run by the processor.


> What are the " absolute adresses of a program" ?

Some machinecode instructions adress memory absolutely - like jumps
to a specific location.. If a fargo program is loaded to an adress,
say $12000 - and makes a jump to another position in the program at,
say $12100, it will only work as long as that program is not moved
to another location in memory. And since The TI92 OS does this to
its variables regurlarly, the Fargo core MUST recalculate these
adresses .. so if the TI92 OS moves our program to $11880, Fargo must
change the jump instruction so it jumps to $11980 instead.

//Sasq (Jonas Minnberg)
 


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