Dave Curran writes about getting some problematic ZX80 BASIC games running on the Minstrel 4D computer.

But when I tested ZX80 Kong, that unfortunately did not work, just giving an odd single line listing. ZX80 Pacman was the same.

The game is written entirely in machine code, and uses the technique developed by Martin Knorth to auto-run upon loading. It first performs an integrity test to ensure that it has loaded from cassette correctly and should an error be detected then a return to BASIC is made and an error message displayed.

I contacted Paul and asked if he could tell me more, to see if that was indeed the problem, and he kindly replied with the information and link to the appropriate page.

I added a quick bodge to test the theory, and it worked first time.

Check out the full analysis (and the beautiful emulation) in the post here.