Re: 65C02 emulation

[Charlie Springer <RAM@regnirps.com>]

On Wed, 27 Dec 2006 21:26:55 -0800, bieling@terra.es wrote
(in article <1167283615.114007.102690@79g2000cws.googlegroups.com>):

> OTOH, if things are done this way, the burden of discriminating what
> has to be read/written from/to the Apple II MLB, may happen to slow
> down quite a lot the emulation speed of the "processor" ARM, but about
> this I have not thought very much yet...?

The ARMs have several memory access modes to handle full speed RAM and slower 
ROM and FLASH plus a mode that can hold till finished. So with the right MMU 
stuff one should be able to read/write at Apple bus speed when needed. All 
the program RAM and ROM space should be copied into fast RAM along with the 
emulator code. FLASH is too slow to use for anything but boot and resource 
storage. I will have to look closely at the current crop of MMU equipped ARM7 
and ARM9 chips. But I'm not going to worry about it till I can emulate the 
6502 with the kind of speed I want.

-- Charlie Springer