New books from Apress

Andy Armstrong andy at
Thu May 25 00:56:20 BST 2006

On 24 May 2006, at 23:38, Peter Corlett wrote:
> Here's some other ROM images for you to play with:

Haha! Thanks. I'll chomp through them.

> You seem to have hardwired HIMEM in your emulator whereas it should  
> arguably
> change itself based on the kind of ROM loaded. When I hack your  
> code to load
> a "HiBasic 3" image and use the correct value of HIMEM, I get this:
> mabuse at dopiaza:~/65Perl02$ ./
>        800
>       B800
>      45056
> ... which sure beats the 1900-7C00 I have on the real Beeb here.

Ah yes - I forgot about the ROM relocation address stuff. I'll bung  
that in. You'll note that I'm using the Tube ROM space at &F800 as a  
general purpose scratch area - for example Perl error messages that  
are being sent to the beeb get copied there. If you compacted that  
area you could build a custom ROM image and load it even higher :)

> Your 6502 emulator lacks a few instructions to get the BBC Master's  
> going though. Wish for a rainy bank holiday :)

They shouldn't be too hard to add - but I was getting keen to start  
using it by the time I got to them :)

Andy Armstrong,

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