Electric Potato
Well-known member
Hey guys,
I've been struggling to get Teensy 3.1 to register MIDI IN using a Sharp PC900V optocoupler despite trying a number of different configurations.
I've tried, among other things :
the MIDI schematic on pjrc, https://www.pjrc.com/teensy/td_libs_MIDI.html
the official schematic at MIDI.org (http://www.midi.org/techspecs/electrispec.php),
I pulled the PC900v out of an old keyboard and put an IC socket where it used to be, so I'm able to pop it back in and confirm that it works fine.
I also know that the serial port rx1 is all set to receive because if I plug/unplug it from pin 6 on the optocoupler I get jibber jabber in the com monitor like sometimes -1's but usually a string of random larger numbers. When I play notes on any MIDI device however, I just get silence
in the serial port.
I'm stumped because I've copied the official diagram, swapping out the 5V connection for 3.3V connection and lowering the resistor,
which is basically what was done here, just with a different IC: https://forum.pjrc.com/threads/27672-Teensy-3-1-Serial-Midi-Input-Woes
just with a different optoisolator, which worked.
would it matter that I'm using a 1N4001 diode instead of a 1N914 on the DIN jack circuit? In the pjrc schematic it's unlabeled so I figured it's not super important.
Thanks so much for any help, it's been frustrating trying to solve what seems like a really simple problem
I've been struggling to get Teensy 3.1 to register MIDI IN using a Sharp PC900V optocoupler despite trying a number of different configurations.
I've tried, among other things :
the MIDI schematic on pjrc, https://www.pjrc.com/teensy/td_libs_MIDI.html
the official schematic at MIDI.org (http://www.midi.org/techspecs/electrispec.php),
I pulled the PC900v out of an old keyboard and put an IC socket where it used to be, so I'm able to pop it back in and confirm that it works fine.
I also know that the serial port rx1 is all set to receive because if I plug/unplug it from pin 6 on the optocoupler I get jibber jabber in the com monitor like sometimes -1's but usually a string of random larger numbers. When I play notes on any MIDI device however, I just get silence
in the serial port.
I'm stumped because I've copied the official diagram, swapping out the 5V connection for 3.3V connection and lowering the resistor,
which is basically what was done here, just with a different IC: https://forum.pjrc.com/threads/27672-Teensy-3-1-Serial-Midi-Input-Woes
just with a different optoisolator, which worked.
would it matter that I'm using a 1N4001 diode instead of a 1N914 on the DIN jack circuit? In the pjrc schematic it's unlabeled so I figured it's not super important.
Thanks so much for any help, it's been frustrating trying to solve what seems like a really simple problem