; enter the machine language monitor CALL -151 ; toggle the speaker and load the accumulator with the "floating bus" value--the byte last read by the video

; enter the machine language monitor CALL -151 ; toggle the speaker and load the accumulator with the "floating bus" value--the byte last read by the video refresh controlled by the video scanner. 0300- AD 30 C0 LDA $C030 ; print the accumulator as a character 0303- 20 ED FD JSR $FDED ; repeat (loop by going to 0x300) 0306- 4C 00 03 JMP $0300 ; run it! (0x300 Go; just like G in your debugger) 300G Running this will display random characters and make noise.