Dear All – just another “vintage LEGO” post … Summary Letting the CodePilot directly look into the light of one of the output LEDs of LEGO Interface A (#9750) makes it happy: A QBasic program for uploading even more complex VLL scripts to this PBrick using only original LEGO hardware (from the 1980’s ) 2 resistors, 2 diodes, 1 red LED, and ½ CD4013 ;) for a total of less than $5: A “serial interface” for directly uploading programs to the CodePilot or the MicroScout PBricks