Sinclair ZX80 / ZX81 Forums

When looking at a disassembled listing forward jumps are always off by one, they don't match the opcodes. For example, 20;01 is listed as JR +2 instead of JR +1, this can be confusing if you don't remember that. On the other hand backward jumps are listed correctly. Bitwise manipulations involving I...

When loading back a saved SCR file it will ovewrite the beginning of the VARS area. This is because the saved XXXX.scr file is 793 bytes when it should be 792 bytes. This is not a new bug it's been around for awhile, I just thought I'd mention it. It can cause problems at times.

Regards;

Greg

This is more of an annoyance than a bug. It occurs when loading the program and a folder is not found. It prints the message then crashes out. Then reloading it works, must update the ini file before crashing.

Regards;

Greg

This is a weird bug, see the attached picture. Almost seems like it's corrupting the ROM image somehow.

Regards;

Greg

This is a problem with ZXPand not the program. When generating standard ZX81 type characters SHREB expects to find the character patterns at $1E00, which are are no longer there because of the ZXPand overlay ROM. Pseudo-hi-res programs also have a similar problem. Try loading the program with the /x...

Here it is with SHREB version 3. I haven't actually tried to figure out how the use the program, but the screen shot shows that SHREB version 3 is working.

Regards;

Greg

Horizontal coords are based on byte positions while vertical coords are based on pixel rows. The max horizontal pixel coord is 255.

More info about SHREB can be found here...

viewtopic.php?f=10&t=1441&p=15136&hilit=shreb#p15136

Regards;

Greg

An error code of "V" indicates a vertical plot parameter is out of range, greater than 191.

Likewise an error code "H" indicates a horizontal plot parameter is out of range.

Regards;

Greg

Some info about the QS HRG board can be found here... http://zx81.ordi5.free.fr/qshrg/ The ROM image is available from there. XavSnap's emulator emulates this board very nicely. http://zx81.vb81.free.fr/ Here's some demos and programs for the Quicksilva HRG. Also includes the "Kweeky" application to...

Thanks, that worked.

FYI, anyone using the ZXMore version, you have to change to UDG mode in the tools options before loading it.

Regards;

Greg