Control Port tester for Commodore C64 (6502 assembler)
Only for digital pins - you can check the ports or joystick :)
Sources in dasm format, compile command: dasm cptester.asm -ocptester.prg
Sprites created in Spritemate (www.spritemate.com) cptester.spm
Starting the program in the VICE emulator: x64 -autoload cptester.prg