MIDI IN Not Functioning & Flashing LCD

Testing/Troubleshooting
1

This is my first and so far unsuccessful attempt at a MIDI-BOX… :frowning:

My MIDI output is working, I was able to receive every 2 seconds:

0001D2AB   1 XXX    F0 Buffer:     8 Bytes System Exclusive

SYSX: F0 00 00 7E 40 00 01 F7

After receiving the first message within 2 seconds I uploaded MIOS_v1_4b.syx, but I did not receive any return from the CORE during upload.  I checked and replace the optocoupler.  This time, just after the upload, the core locks up and the LCD backlight flashes (about every 4 seconds.)  I had to restart MIDI-OX and my MIDIbox, which I then receive the message:

00002904  1  –    F0 Buffer:    8 Bytes  System Exclusive

SYSX: F0 00 00 7E 40 00 01 F7

and it repeats every 4 seconds (with a flash from the LCD.) ???

I checked my PC’s MIDI using a coupler looping in to out and MIDI-OX INPUT matches OUTPUT

Thanks

2

Follow this instructions:

http://www.ucapps.de/howto_debug_midi.html

thanks!

3

Thanks for responding so promptly :slight_smile:

I have run all the tests in MIDI Troubleshooting and these are my results:

  • I purchased the PIC programmed from CoinOptech.com, should I download IC-Prog to verify the burn?

  • A 10 MHz Parallel Cut crystal has been used

  • All 5 Jumpers are in place

  • Solder joints have been checked and are acceptable

  • Vdd at all testpoint checks ok at 5.02

  • Gound supply checks ok at all points

  • MIDI plug polarity is correct

  • Polarity of the protection diode is correct

  • When connected to MIDI Outport the Diode flashed once every 4 - 7 seconds

  • PC crosslink is correct

At the PC site:  Inputs are not attached to Outputs

 I tested the MIDI Interface of the computer with a loop back coupler and it checks out ok.

I ran the MIDIIN Debug:

 The LED did light.  When I send SysEx data, the LED did flicker.

I believe the PIC is now receiving SysEx but not responding during the transfer.

4

I happend to get it to work!!!  ;D

I set Low Level Output Buffers to 640 Bytes and Delay after FF: to 1500 MiliSeconds

I was able to upload both mios_v1_4b.syx and midibox64_v2_1 main.syx

I hope this might help anyone else with the same prob.

Thanks

5

Hi Jost,

thanks for the input! Other interfaces are not working with a buffer size < 2048, so it’s difficult to specify values which fits with all requirements. :-/

Maybe with the upcoming Java environment this will work better without modifying any value.

Best Regards, Thorsten.