Denial

Problem. The keyboard buffer is pretty small (631-640 in memory). My proposal would only be good for deleting 9 lines. 63998 INPUT"DELETE LINE";S:INPUT"UP TO";E 63999 IFS<=ET{SHIFT-H}?"{CLR}"S:?"S="S+1"{LEFT}:E="E"{LEFT}:G{SHIFT-O}63999":P...

You might take a look how my implementation of Moon Patrol handles the animation of the UFO and the bullets in front of the background with stars and scrolling mountains - see especially the lines 15 to 23 in the file 'MOON PATROL 2' of the disk image. That should give you some ideas which can also ...

What is the easiest way to transfer the program to my vic? I have just the vic and a Mac and a PC. No disk drive yet. If you don't have a disk drive (yet), a SD2IEC is most probably the best bet. With this device, you can use SD cards to transfer programs and disk images between PC and VIC-20. [......

Even though the sample image is missing in the other thread, that's pretty much the same thing jibberjabber encountered on his VIC-20. See the thread ' Gaps between characters on video output ', and the answer by me. In short: Yes, it's quite normal. It's aggravated on most modern displays. The S-Vi...

How about [...] The 'canonical' solution for this kind of memory management is a two-filer: The first part POKEs user-defined characters, machine code, and other data into memory, perhaps displays a title screen and instructions, and then the main program is being loaded and run. Freeing memory by ...

The program would be a collection of BASIC line[s] I commonly use (joystick routines and such). That's an interesting application for itself. I'm assuming that this is also supposed to run on the real iron. :) Of course you could keep the different code snippets as single files on a disk (or disk i...

i don't know that "40 columns manager" - but i'd assume that it creates a 40 columns display in software, which is quite a bit slower than normal text screen (and the test also takes PRINT speed into account, even including scrolling the screen - which will have a huge impact on speed) MG...

This says PAL only?? [...] Glen already stated the reasons for this in this thread: An identical NTSC version isn't really possible - *every* [cycle] is used in a raster line, with no branching. To write this for NTSC would mean dropping the dynamic colouring for the main character. and Perhaps the...

Jeff, for what reason would you want to delete, add, or possibly also modify lines from within a program, besides the odd 'insert expression for a function plotter', 'create a data loader', or 'tokenize a PETSCII SEQ file'? We had a similar discussion about this some time ago, see 'Reflection in BAS...

For those concerned, here's an updated data loader for the streamlined version at 673, *including* the CLD, but leaving out save/restore for the ZP bytes. I could strip off another few bytes: bit 8 of $9003 does not contain bit 9 of the screen start address in the VIC bank, but bit 0 of the raster c...

I took another look at the garbled display. It is possible, that the VIC registers are wrongly initialised, so the screen display start address now points to uninitialised memory. For a short explanation, '@' and the checkerboard character are 0 and 255, respectively. You find this two-byte pattern ...

Good job with all the lastest adjustments!

I found the link of the picture 'until 5 posts, possible spammer' displays as broken (at least on my web browser). Unless it is planned to revive that picture, it should now possibly replaced by a suitable non-vanity Rank.

Just like the Zp $03-$06 and $FB-FE are never used in CBM Basic or the Kernal, there is no instance of a SED. So a CLD would not be needed.... :D I know that. Don't you think that doesn't preclude that user programs might use decimal mode? That consideration is especially important, as the free mem...

The code below takes 92 bytes and fits in the 673-767 area. Start with SYS673. Now, that's quite a feat. And you even kept the niceties I put in to adapt to the different RAM configurations, especially regarding the screen and colour RAM base addresses. 8) I'd still keep the CLD in front of the int...

why didn't they make the most generic parts of the BASIC language (write to the screen, read from the keyboard, add numbers, concatenate strings, etc.) compatible across different machines You're talking bullshit here. Of course these operations you cited worked source-code compatible across most p...