BBC Basic (Was: New books from Apress)

[Andy Armstrong]

(oops - forgot to change the subject - sorry)

On 25 May 2006, at 00:56, Andy Armstrong wrote:

> On 24 May 2006, at 23:38, Peter Corlett wrote:
>> Here's some other ROM images for you to play with:
>>
>> http://www.mdfsnet.f9.co.uk/Software/BBCBasic/BBC/
>
> 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$ ./65Perl02.pl
>>> PRINT ~PAGE
>>        800
>>> PRINT ~HIMEM
>>       B800
>>> PRINT HIMEM-PAGE
>>      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 BASIC
>> 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, hexten.net
>
>

-- 
Andy Armstrong, hexten.net