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BigDumbDinosaur
PostPosted: Mon May 30, 2022 8:19 am 
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JimBoyd wrote:
A jump table is a way to future proof your design.

Probably the best-known use of a jump table is in the Commodore “kernal,” which every eight-bit Commodore machine has had.

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Sean
PostPosted: Thu Jun 02, 2022 2:08 pm 
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Absent a software interrupt capability, it seems a good approach. Are there others?

BigDumbDinosaur wrote:
JimBoyd wrote:
A jump table is a way to future proof your design.

Probably the best-known use of a jump table is in the Commodore “kernal,” which every eight-bit Commodore machine has had.
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barrym95838
PostPosted: Thu Jun 02, 2022 3:16 pm 
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Several of the 6502 pioneers like Woz didn't bother with JMP tables or complex BRK handlers, although convoluted RTS tables were definitely on the menu. They packed their ROM code as tightly as they possibly could, and let the entry points fall where they may. Many of those entry points became "standard", like the Apple ]['s $FDED for COUT and -151 for the monitor prompt, and the burden fell on the person updating the ROM code in subsequent incarnations to keep that functionality as well as he or she could. When you're a pioneer (or just want to act like one), you can be afforded some artistic license in my book.

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