Re: A85: Rigel, where'd it go??


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Re: A85: Rigel, where'd it go??



On Mon, 13 Oct 1997 17:47:14 -0500, you wrote:

>Sam Davies wrote:
>> 
>> Ben Sferrazza wrote:
>> 
>> > Michael Pearce wrote:
>> > >
>> > > And don't forget that program sizes are smaller in Rigel than they are
>> > > in Usgard.
>> > >
>> > > -mike pearce
>> > >
>> > > BTW, does it take 2 additional bytes for every "&" you stick in a
>> > > Usgard program to put in the relocation table?
>> >
>> > Sure.  Since Usgard uses some sort of fixup table for all relocation,
>> > you must have at least two bytes for every fixup.  Ah, the beauty of
>> > fixed address relocation.
>> 
>> Actually, no!  It takes in most cases only *1* byte to store the address!
>> How can we do this, you ask?  We store addresses relatively -- that is we
>> store the offset from the last relocation address.  So if there are two &'s
>> within 256 bytes, it will only take one byte :)
>>     Sam
>> 
>> --
>> Sam Davies <sdavies@mail.trilogy.net>

So does this scheme still work if you put the graphics, sprites,
whatever that doesn't have relocation, in the middle of you code
segment?  For every 256 bytes of code, is there a new 16 bit address
in the table?  If not, that would definitely cause problems.  But i am
sure you guys thought of that.

-mike pearce


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