Blue lines when redefining character set on Vic 20

[Frozone212]

ok so since I can't properly put this into words, I'll just leave the video here. It explains better than I can anyway.

 

Need help here

if anyone is wondering it's from the book Compute's Creating Arcade Games on the VIC

Creating arcade games on the VIC : Camp, Robert : Free Download, Borrow, and Streaming : Internet Archive

[carlsson]

Simple. You have an inverted heart on line 20 (clear screen) without PRINT so what happens is that the program exits with a syntax error.

 

Some ideas: Always do the memory adjust POKE first (only 56 is required, followed by CLR). Change the VIC register first after the loop is finished. Optionally clear screen before the loop as you already are doing.

 

Edit: Perhaps you are confusing the command CLR with the graphic symbol for CLR/HOME. Then it makes sense.

Edited August 11, 2022 by carlsson

[Frozone212]

speaking of which, I'm looking for a CRT image of the Super expander cartridge. The two from Zimmers won't load correctly