MIDIBOX SID - DIN problem(solved)

Testing/Troubleshooting
1

Hello to all!

I’m currently building a midibox sid using aviswhowtech’s parts.

My current setup is:

-mbhp_8xsid_c64_psu_optimized;

-pic core with pic18f4685 and 4x20 LCD;

-2x sid modules (for stereo sid);

I’ve uploaded the sid test_tone app and everything turned out alright, i got a triangle waveshape output on each of the sid modules.

When i connected the SRIO chain to the core module for the minimal configuration setup(9x buttons + 1 encoder) and using the standard pin setup, i realised that only the button connected to SR1 D7 would react on the midibox.

My first reaction was to test the SRIO chain with an arduino and check if the buttons were responding properly. The test was 100% successfull so i guess the problem wasn’t about the shiftRegisters or short circuits on the SRIO chain modules.

After some toubleshooting and investigation I realised that I was getting the problem described here in the section “Testing Shift Registers Connections” (almost at the end of the page).

I think this is my problem cause I’ve uploaded midio128 app and once the SR1 D7 button is pressed it will make the midibox output a bunch of midi notes and cc messages.

So I’ve uploaded the srio_interconnection_test app in order to check the SC and RC pins in my core.

The result was unsuccessfull!

I got the following voltage values:

_____KEY C____________________KEY C#______________KEY D____________

GND__–>__SO = 5V________GND__–>__SO = 0V________GND__–>__SO = 0V

GND__–>__SI = 5V________GND__–>__SI = 5V________GND__–>__SI = 5V

GND__–>__SC = 0V________GND__–>__SC = 0V________GND__–>__SC = 0V

GND__–>__RC = 0V________GND__–>__RC = 0V________GND__–>__RC = 0V

GND__–>__VD = 5V________GND__–>__VD = 5V________GND__–>__VD = 5V

Then I went searching on the forum and found <___base_url___>/index.php?/topic/13672-din-module-is-not-working/page__p__122960__hl__din__fromsearch__1&do=embed&embedComment=122960&embedDo=findComment post so I decided to use an osciloscope to check the signal on pins 21 and 22 of the pic(RC and SC).

PIC PIN 21 (RC)

PIC PIN 22 (SC)

As you can see the signal on pin 22(SC) has much more amplitude than the signal on pin 21(RC). Is this normal??

I apreciate if anyone out there can take some time to help me cause I’m really out of ideas of how i should proceed next.

Thanks in advance…

analogue_mo

2

Well, I just found out what the problem was…Apparently I’ve got a messed up PIC.

First I took it from the midibox_sid and tested it in a separate core module I had laying around. I uploaded the midio128 app and got the same response from the SRIO chain(the button connected to D7 outputs a bunch of midi messages and none of the other buttons works).

Now I know that the problem is not on the core module.

Lucky for me I allways tend to order this kinds of things in pairs, so I had another fresh PIC 18F4685. I stuffed it into the midibox sid core module, uploaded the midibox sid app and everything started functioning.

3

Glad you got it working! Did you try reuploading MIOS to the pic? A corrupt upload can basically do pretty much anything :slight_smile:

4

Hi nILS,

Yeap, I started by uploading MIOS_v1_9g…yet, I did it only once…I never got to re-upload it but Ill try and do it later on.

Right now I’m all about testing this new wonderfull toy =)

I’m going for the full step C surface so there is still some work to be done.

Going back to the lab…keep midiboxin!Cheers.

analogue_mo