Date   : Wed, 24 Aug 1994 07:38:51 +0100
From   : jfid@... (James Fidell)
Subject: Re: IIITTTTT WWWOOORRRRKKKKSSS!!!!!!!

"Chris L. Rae" wrote:

> 1. Errors seem to work okay (except ESCape, of course) and except the 
> "Silly" one, I know not why. However, there is a spurious character 
> before each error message. I'm not exactly sure why.

I'd put a modest amount of money, or a few beers, on this being because
you aren't stacking the return address correctly when you handle a BRK.

Unlike JSR, where the return address pushed on the stack is the actual
return address less one, BRK and hardware IRQs put the exact return
address on the stack.

> 2. (This one is *wierd*) When I type "List" a few times my emulator halts 
> with a duff instruction opcode!

Can't help you with this one, I'm afraid.

> 3. I can type in the 256^3 loop program but it won't run - emulator hangs 
> completely. Very odd. Anyway, I was wondering - I used INA in my 256^3 
> loop but this doesn't compile on a 6502 standard BASIC. What can I do 
> instead?

If you're using A for the outermost loop, you could use :

       TAX
       INX
       TXA

James.

-- 
 "Yield to temptation --             |
  it may not pass your way again"    |     jfid@...        
                                     |
        - Lazarus Long               |              James Fidell