Denial

how do you print the code of the the prg files There's the petcat utility bundled with VICE, which converts *.prg to ASCII *.txt and vice versa. It has some weaknesses though, because graphic characters with the C= key are quoted as hex-codes only. Alternatively (again using VICE) the file is loade...

KingTrode wrote:[...] it does need some sound FX [...] Probably "Dice Throw" / "Invalid Selection" / "Succesful Score " or something along those lines.

Oh, I thought you'd add some speech synthesis if you were going to use expanded memory.

I already sent it to Nigel as e-mail, together with an explanation how the exploit works.

Here's my ultimate-rule-bending entry: 'bird.prg'.

Kweepa's program could go into a single line, BTW.

I'm sorry, but I wouldn't want an automated script to change my posts. Furthermore, I suppose you couldn't guarantee that any *.prg file runs without hassles on your emulator. If you add the link manually in an own follow-up post, that's fine and indicates you checked it at least. But if such an aut...

Okay then, the +3K RAM expansion just moves the BASIC start from $1001 down to $0401, but leaves screen memory and colour RAM at the same place as in the unexpanded configuration. Most BASIC programs written for the unexpanded VIC-20, even those that use redefined characters, run without any issues ...

Indeed, the form: IF <condition_1> THEN IF <condition_2> THEN ... instead of: IF <condition_1> AND <condition_2> THEN ... is quite often found in BASIC programs, and is easily generalised for more conditions. Note however these are only equivalent, when all conditionals are Boolean expressions. If y...

Mayhem wrote:+3K RAM provides its own problems, [...]

What kind of problems?

Are the "and" and "or" operators short-circuited in basic v2? No, they aren't. Expressions are always evaluated in full. Furthermore, AND, OR and NOT operate on signed 16-bit quantities. The result of a relational operator ('=', '<', '>' or any combination thereof) is -1 if the ...

So any input on this front is most welcome. If you want to keep it somewhat restrained, you should consider a +16K RAM expansion as 'soft' limit. At the time, this was the biggest single RAM expansion cart sold by Commodore (the VIC-1111). Anything bigger than that would have required either a cart...

The screen editor of the VIC-20 accepts up to four physical lines as a single logical line, i.e. 88 characters. With abbreviations (for example, ? for PRINT, F SHIFT-O for FOR, N SHIFT-E for NEXT, etc., see the VIC User's manual), you can enter some more code into these four lines. When this line is...

[...] a little (perl?) script that creates basic lines from the coordinates. My problem is how to write the petscii chars and rvson/rvsoff, so that they paste correctly into vice or basedit. As I wrote elsewhere , the copy&paste facility of VICE is just unusable beyond simple text I/O. Again, w...

Why this intermediate step with a list of pixel co-ordinates?

You can convert the B/W image directly to a BASIC program which consists solely of PRINT statements (and two POKEs into screen and colour RAM for the bottom-right character), which is much more efficient speed- and memory-wise.

Hmm? I was under the impression, that NTSC had a different pixel aspect ratio more like 1.5:1 (which would correspond to 0.750 in VICE). :? I got my value a long time ago by measuring the width and height of the text window of the VIC-20 on a TV set, which had been confirmed before to draw perfect c...