[SOLVED] MBHP_CORE sends only 0xFF MIDI messages

[alchemist]

Hello,

 

At my first run, the MBHP_CORE module sends only 0xFF messages in the Midi Out, and MIOS Studio cannot communicate with it.

I tested it in Windows and Linux, with 2 different MIDI interfaces : an edirol UM-880 and a "bad" ESI MidiMate II.

 

And I don't see anything on a 40x2 LCD display...

 

What can I check to find out how to find the problem?

 

Thanks in advance!

Edited December 21, 2013 by alchemist

[alchemist]

The loopback test on the module works.

I will check the rest of the check-list, maybe there is a short-circuit of bad solder.

[TK.]

Did you flash the bootloader into the PIC with your own programmer?

Probably it hasn't written all-zero into the ID field.

 

This can be fixed with TEST_SW2 http://www.ucapps.de/howto_debug_midi.html

 

Best Regards, Thorsten.

[alchemist]

It was flashed by Mike.

 

I don't see +5V on TX and RX : http://www.ucapps.de/howtodebug/mbhp_core_extract_measuring_vdd.gif

[TK.]

Ok, then it's clearly a soldering issue. Check the whole +5V supply track and all solder joints related to this.

 

We had a very similar case in the german section of this forum just 4 days ago: 

And again... it was just a cold joint.

 

Best Regards, Thorsten.

[alchemist]

Thank you very much, I will check that later (now time to go to bed).

 

Even if it doesn't work at the first time, I am happy some parts work.

That board was quite more difficult than the Elex PCBs 25 years ago :shifty:

[alchemist]

Hello,

 

[EDIT: changed pin 26->25, this is a TX problem]

 

I checked the soldering and Vdd, ground. Everything seems OK now  except on pin 25 (Tx).

I have 5 V on the PCB at the soldering of pin 25, but 0.8V on the pin 25 itself. I checked that the soldering is OK and I got continuity between the PCB and the pin.

 

And the MIDI out messages are still garbage (FF, control change, or note off).

 

The main.hex of mios_bootstrap_picstart_workaround_v1.zip cannot be uploaded (checksum error).

Edited December 19, 2013 by alchemist

[TK.]

The main.hex file is only intended for PIC programmers, not for MIOS Studio!

But since you got the PIC from Mike, the IDs should already be programmed correctly.

 

 

And the MIDI out messages are still garbage (FF, control change, or note off).

 

Aha, now it also sends other events... was this also the case before the soldering fixes?

 

When do you get this output: once after power-on, or continuously?

 

And do you always get the same events after power-on, or are they changing?

 

Best Regards, Thorsten.

[alchemist]

Hello,

 

I fixed 2 short-circuits (I had a too big soldering tip at that time) and probably 2 cold solder.

Before the fixes, it was only 0xFF, and now, it changed, but when I reply (and checked again some soldering), it's again 0xFF

 

I don't see always messages in the MIDI monitor, but my MIDI interfaces LEDs are always on.

 

With MIDIOX, I see at the moment some 0xFF's when I power off the core module.

 

I will recheck the components and soldering saturday. I will find it !!!

 

 

When I replug the MIDI cable, the MIDI messages change : CC's, Note On, Note Off...

 

Example from MIOS Studio Linux

Scanning for MIDI Inputs...
[1] Midi Through
[2] MIDIMATE II (1)
[3] MIDIMATE II (2)
MIDI Monitor ready.
[10202.628] c0 78   Chn# 1  Program Change 120
[10202.632] ff
[10203.555] e1 00 00   Chn# 2  Pitchbend -8192
[10207.340] e1 00 00   Chn# 2  Pitchbend -8192
[10211.125] e1 00 00   Chn# 2  Pitchbend -8192
[10214.910] e0 00 00   Chn# 1  Pitchbend -8192
[10218.695] e0 00 00   Chn# 1  Pitchbend -8192
[10221.845] ff
[10221.845] ff
[10221.846] ff
[10221.847] ff
[10221.849] ff
[10221.850] ff
[10221.851] ff
[10221.854] ff
[10221.854] ff
[10221.855] ff
[10222.791] e0 00 00   Chn# 1  Pitchbend -8192
[10226.576] e0 00 00   Chn# 1  Pitchbend -8192
[10230.361] e0 00 00   Chn# 1  Pitchbend -8192
[10234.146] e0 00 00   Chn# 1  Pitchbend -8192
[10237.931] e0 00 00   Chn# 1  Pitchbend -8192
[10241.716] e0 00 00   Chn# 1  Pitchbend -8192
[10245.501] e0 00 00   Chn# 1  Pitchbend -8192
[10249.286] e0 00 00   Chn# 1  Pitchbend -8192
[10253.071] e0 00 00   Chn# 1  Pitchbend -8192
[10256.856] e0 00 00   Chn# 1  Pitchbend -8192
[10260.641] e0 00 00   Chn# 1  Pitchbend -8192
[10264.426] e0 00 00   Chn# 1  Pitchbend -8192
[10268.211] e0 00 00   Chn# 1  Pitchbend -8192
[10271.996] e0 00 00   Chn# 1  Pitchbend -8192
[10275.781] e0 00 00   Chn# 1  Pitchbend -8192
[10279.566] e0 00 00   Chn# 1  Pitchbend -8192
[10283.351] e0 00 00   Chn# 1  Pitchbend -8192
[10287.136] e0 00 00   Chn# 1  Pitchbend -8192
[10290.921] e0 00 00   Chn# 1  Pitchbend -8192
[10294.706] e0 00 00   Chn# 1  Pitchbend -8192
[10298.491] e0 00 00   Chn# 1  Pitchbend -8192
[10302.276] e0 00 00   Chn# 1  Pitchbend -8192
[10306.061] e0 00 00   Chn# 1  Pitchbend -8192
[10309.849] e0 00 00   Chn# 1  Pitchbend -8192
[10313.632] e0 00 00   Chn# 1  Pitchbend -8192
[10317.417] e0 00 00   Chn# 1  Pitchbend -8192
[10321.202] e0 00 00   Chn# 1  Pitchbend -8192

Edited December 19, 2013 by alchemist

[alchemist]

Aha ! I see some other short-circuits in the MIDI out path, when it crosses a connector...

But still the same noise after the clean-up.

Edited December 19, 2013 by alchemist

[alchemist]

SOLVED !

There were small short-circuits. I fixed them with a screwdriver (test CORE10).

 

Operating System: MIOS8
Board: MBHP_CORE or similar
Core Family: PIC18F
Bootloader is up & running!

Edited December 21, 2013 by alchemist

[TK.]

:thumbsup:

[alchemist]

Yeah !

 

Next step : finish the MBHP_SID board #1 and connect it to the CORE :)