Denial

For example, if I want to include #include <myfunction.h> I need to write the myfunction file, with the functions signatures, and teh myfunction.c with the code implementation. The compiler return me an error, because don't find the files myfunction.h and myfunction.c... I'm sorry to write this, bu...

You should be able to cut the JMP $C474 I just tried it out. Sadly, it doesn't quite work. Here's the remainder of SYS, when the return-address of the SYS call is preserved with JMP $C659: .E141 6C 14 00 JMP ($0014) ; call user routine with $E144 - 1 on stack .E144 08 PHP ; <- re-entry point .E145 ...

You should be able to cut the jmp $c474 [...] [t]his was previously discussed here: [...] Indeed, that one would save 3 bytes. Wow, this thread is from 2005! Perhaps the print line could be made shorter and/or easier to type by op[t]imizations specifically targetting the number of escape codes and/...

[...]it looks like an UNNEW. Spot on! :D Here's an assembly listing, without instruction addresses as the code is fully relocatable (which is also the reason SYS256*PEEK(648) works at all): LDA #$01 TAY STA ($2B),Y ; write a non-0 value to the first link-pointer JSR $C533 ; re-chain lines (which ma...

I did notice that there was a 0 when I LISTed the program. Indeed you get that or a similar (and admittedly useless) result when you run this line on a VIC-20 which has just be powered on. You might want to use this code under other circumstances though ... citing examples would give it away alread...

Why did no one think of this back in the day? That looks like a general scheme you like to put questions. People in the past were likely smarter than you might think they have been. DATA loaders with numeric values were an easy method in those days to transcribe a (small) machine code program from ...

Just stumbled across this in another forum:

http://www.youtube.com/watch?v=JNQWIXCgxLw

Has anyone ever tried to produce executable machine code by putting characters on the screen? From the CPU's view, there's no difference between RAM committed for screen display and other RAM. I've seen quite a few uses, for example decompressors which execute in the screen buffer to unpack data in...

Hi, Nibby99, this thread should shed some more light on this. ;) In short, exponentiation is a much more complex operation than multiplication. For this reason, it is also prone to rounding errors, that's why you get a non-integer result with 7^2. VIC BASIC doesn't do any clever optimization tricks....

Updating some links to files so thought I'd add this one. Some time ago I posted a *.d64 with some other mixed-mode pictures in the thread about the MG batch suite ( link ). Does GIMP allow for a display with non-square pixel aspect ratio? After all, the real resolution of MG pictures is 160x192, n...

What do you guys make of PETSCII? In text mode, PETSCII is quite nice to draw boxes/frames. With other characters you can easily draw progress bars in 2D. Big captions for title screens ( Sokoban , TRON ) ... I also have seen quite impressive pictures drawn from PETSCII characters, on the C64, thou...

For example if my program was from 6566 to 7168 I would POKE43,0:POKE44,26:POKE55,0:POKE56,28 [...] The last two should read POKE45,0:POKE46,28. POKEs to the addresses 55 and 56 set the top of available memory for BASIC, which in themselves come in quite handy to protect user defined graphics from ...

Welcome back!

Nothing beats the real iron.

There's a nice sticky thread here in the Programming Section about ROM calls and other tricks . Within that thread, SYS57809 to set up file name and device address to load and save blocks of memory was pointed out in this post dating from 2006. From assembly the KERNAL routines SETLFS ($FFBA) and SE...

Aleksi and Viznut are both registered here, but you can count their posts by the fingers of two hands (and maybe the feet's toes, too).