NASA Won't allow you to use recursion, I think they forbid heap usage too. There will definitely be documentation on their requirements.

After all... Who wants to loose a multi-billion pound mission with years of work behind them and jobs on the line over a single bit out of place.

I'd imagine porting code from one architecture to another has traps for the lazy too.
I really wish we could get off this whole, "Errors happen because programmers are 'lazy' thing." All humans make errors, and it's not because they're lazy, it's because they're efficient .

If you don't believe ...

if there's one thing I've learned about software over the years its that no matter how hard you try, there's always one little bug left. I'd imagine porting code from one architecture to another has traps for the lazy too. In a way, when writing Z80 code I was spoiled for registers. I wonder if ...

So far I'm pleased that this little bugfix seems to be agreed with.

Now, as to why someone wouldn't spot this bug, I think its down to SWAP being a very uncommonly used command that isn't implemented on that many versions of BASIC and so wouldn't affect all that many people.

To err is human, to ...

I think I found and fixed a bug, but before declaring it done, I'd just like for all you beautiful people to just look it over and see if I've missed any subtleties.

; perform SWAP

LAB_SWAP
JSR LAB_GVAR ; get var1 address
STA Lvarpl ; save var1 address low byte
STY Lvarph ; save var1 address ...

Well that looks interesting, not that I want much code to depend on critical timings, magic numbers, self modifying code etc, but it has it's place. Is this open source?

Do you have a schematic we could see?

I don’t know why, but I woke up in the middle of the night with the idea of a two pass method of renumbering that mostly works. Then I realised that there would be a problem if someone put say for instance a GOTO that went to a nonexistent line... Oh dear.

I thought the IRQ support on EhBASIC was somewhat broken, but that is a good point I'd forgotten about.

Since this post has been up for a little while and nobody has replied, I’m going to assume this is an untrodden path and put it on my todo list. If I produce anything to be proud of I’ll post it.

Hey! Has anyone implemented a renumber command to EhBASIC? I don't feel I should be re-inventing the wheel if it's already been done. Not only that, but I haven't yet dug into what's involved and so don't know how big a challenge it might be. I don't think it's going to be impossible but I don't ...

I just thought I'd pop by to say thank you for this post and Daryl for his code here. I didn't realise I'd be needing to update any pointers upon loading BASIC code until things went sideways but once again, it's the brains trust to the rescue.

I'll set it up Friday and see if it's better than the experience I'm getting now. I'll let the world know if things work better natively with it since others might appreciate such info. Right, I've gotta go read up on tapes. I'm building a tape interface for the ToE (not because it's any good but ...

Well, (shuffles shoes and sulks) I do have an old Athlon XP box doing nothing but getting in the way under the desk. I suppose I could use that and certainly find avoiding WinBlows makes for some interesting tool choices.

Might there ever be a Linux native build of Kowalski Simulator? I've been running it in Wine for a long time but there have been issues that just might be because of that.