Thanks Kai... Looking to your code I feel more relieved, my code wasnt SO wrong.

in fabrication of mark
MOV TEMP,#4

shouldnt be MOV TEMP,#8 ?


Also:

                MOV SBUF,#0             ;send START-byte

                ;Wouldnt be nicer to make the MIDI verification here?

                JNB TI,$                ;byte sent?
                CLR TI                  ;prepare UART for next sending
                MOV TEMP,#4
                DJNZ TEMP,$             ;2 stop bits >= 8µsec

 

I having a hard time looking for a place to test the project, after testing I place a reply with results here.