Date   : Fri, 15 Feb 2008 09:12:20 +0000 (GMT)
From   : tommowalker@... (Tom Walker)
Subject: BBC FPGA Boots to BASIC... almost...

> I need to check if it's jumping to &8000 while it's running... or maybe 
> BASIC needs the VIA timer interrupts or something else I haven't
> implemented yet...

OS 1.2 + BASIC should get to the > prompt with no interrupts at all.

> > They need to return &FE instead. ie. the high part of the address.

> Ummm, OK, but can you explain why that's the case?

Because there's no device there, nothing gets put on the data bus, so the
6502 reads what was last there, which is almost always the high byte of the
address.

Tom


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