SEQV4 with integrated 16x8 BLM

"…4x16 BLM which was provided by MBSEQ V3…"

Does this mean, that V4 doesn’t support the 4x16 BLM?

Actually it is supported, but the design is outdated.

With the 4x16 BLM which is directly connected to the DIN/DOUTs of the core it won’t be possible to provide the features of a BLM16x16+X (which is running on a separate core and communicates via MIDI with the MBSEQ V4), therefore this expired solution isn’t “promoted” from my side anymore to avoid that somebody things that he gets something which is equivalent.

The configuration of the directly connected 4x16 BLM has to be done in the MBSEQ_HW.V4 file, search for the keyword “BLM”

Best Regards, Thorsten.

Thank you a lot for this explanation!

Things are now more clear to me.

I finally got life sign from my BLM.

But then:::…

While testing the underside of the DIN module which were connected to anodes of the “button-diodes” got contact with conductive material…BIG MISTAKE, I know…

Happily, everything else still works, but I guess the DIN and DOUT-modules which were connected to the BLM are broken..

I hope the BLM is still ok…I will see…

:whistle:

With a bit of luck only the 74HC595 and/or 74HC165 have to be replaced… :-/

Best Regards, Thorsten.

With a bit of luck only the 74HC595 and/or 74HC165 have to be replaced… :-/

! Thank you TK. !

I replaced them, but no luck this time…

…I hope my BLM isn’t damage. I will see when I will test with new DIN/DOUT…

Ok - my BLM is still not working

I found out, that my new DOUT and DIN modules which connects the BLM are working correct.

So there are two possibilities left:

  1. There is something wrong with the way I connect the BLM to these DOUT/DIN
  2. My BLM isn’t soldered correctly

Because I think the second one is more likely, I now want to find out, how I can messure if my BLM is soldered correctly:

I have already messured the following things:

  1. the diodes - in one way current is running, the other way not.
  2. the LED’s - are working (tested with a LED tester)
  3. each rows are connected (“zero” resistance)
  4. each coloumns are connected (“zero” resistance)
  5. http://discourse.midibox.org/t/topic/15461

How is the matrix driver working?

Is it sending 3 volt of direct current in the LED anodes(coloumns) and setting the rows which are not wanted to light on high current(so that the other LED’s will get high current on both cathodes and anodes)?

Can I somehow “simulate” the matrix driver with my multimeter?

I have a really simple one, but if I would send 2.5V direct current in for example couloumn 1 (anodes) and setting COM/ground to a row 4, the 4 led’s in the coloumn light && I will not damage anything?

(I’m sorry I have pretty much no knowledge to electricity stuff..)

Yippiiee I found the button_duoled_matrix_v1_2c.zip & sm_c_example1_v1c.zip at the mios32 download section

So I have new possibilities to test tomorrow -

thanks TK for all this material…

Yippiiee I found the button_duoled_matrix_v1_2c.zip & sm_c_example1_v1c.zip at the mios32 download section

I only own a STM32, this apps are for MBHP_CORE.

I’m pretty lost. I guess the matrix was too big a project for me (all the other elements of the SEQV4 works).

The worst is, that I don’t have any clue how to start troubleshooting this problem.

I think i will try to build a little test program building upon the blm.c/h files in the modules library…

(I hope I can’t damage anything…

There’s already a MIOS32 app here: http://www.svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fcontrollers%2Fblm_scalar%2F

There’s already a MIOS32 app here: http://www.svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fcontrollers%2Fblm_scalar%2F

Thank you for the advice. But I think this isn’t compatible with the schematic(4x16BLM) that I’m using…?

Sorry, you are correct.

I think this is the one you should use as a base, but there are some others in the example folder too: http://www.svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fexamples%2Fblm%2F

I think this is the one you should use as a base, but there are some others in the example folder too: http://www.svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fexamples%2Fblm%2F

Great. This is exactly what I was looking for!

Thank you.

The program is running, but no life sign from the BLM.

…but I get a lot of debugging messages on the terminal: “DIN_BLM_NotifyToggle(n,1)”, with n constantly changing from 0 to 31.

This function should only print this message with a changing value at the input n. What could this “random” variation mean?

…but I get a lot of debugging messages on the terminal: “DIN_BLM_NotifyToggle(n,1)”, with n constantly changing from 0 to 31.

This function should only print this message with a changing value at the input n. What could this “random” variation mean?

There is probably a problem with the RC signal between core module and the DIN shift registers.

This signal latches the values before shifting, and if it isn’t connected you will get random values.

Beside of this: are you able to control the LEDs by sending MIDI notes to the core?

e.g. with the virtual keyboard of MIOS Studio… ensure that channel 1 is connected. The core will output debug messages whenever a matching event has been received, and the LED state should change.

Best Regards, Thorsten.

Thank you so much for your help!

There is probably a problem with the RC signal between core module and the DIN shift registers.

This signal latches the values before shifting, and if it isn’t connected you will get random values.

Ok. When I connect normal button’s (to the same DIN module) according to this schematic and the 010_din tutorial app, everything is working fine. Is this in conflict with your idea, or could there still be the problem with the RC signal?

Beside of this: are you able to control the LEDs by sending MIDI notes to the core?

e.g. with the virtual keyboard of MIOS Studio… ensure that channel 1 is connected. The core will output debug messages whenever a matching event has been received, and the LED state should change.

I’m sorry that I didn’t mention:

I can’t control any LED. The terminal is printing that the core receives midi notes/events (on channel #1), but no LED reacting neither glowing.

(But the same here : with the same DOUT module and standard LED connection, no problems….)

Very strange!

DIN and DOUT module is working, but you will get a lot of MIDI events once your BLM is connected.

How to check that the BLM application is scanning the keys: disconnect the BLM hardware, and short a DOUT pin with a DIN pin which is normally connected “between” a button.

-> only a single MIDI event should be triggered.

E.g. take this schematic as a reference: http://www.ucapps.de/mbhp/button_duoled_matrix.pdf

Take a cable and connect it with D0 of DEFAULT_SRM_DIN_L and D7 of DEFAULT_SRM_DOUT_CATHODES1 -> do you get a single MIDI event, or multiple events?

Try also other pin combinations.

If this test is working, then it could make sense to think about unusual things:

  • maybe the cable between core and BLM is too long?

-> What is the cable length?

  • powering problem once multiple LEDs are turned on?

-> do you power the MBHP_CORE_STM32 module from an external PSU, or via USB?

-> are you using an externally powered USB hub, or is the module directly connected to your PC?

Best Regards, Thorsten.

Thank you very very much!

!! I will test as soon as possible !!

:: )

It took a bit longer than expected, but finally I tested what you (Thorsten) proposed:

How to check that the BLM application is scanning the keys: disconnect the BLM hardware, and short a DOUT pin with a DIN pin which is normally connected “between” a button.

-> only a single MIDI event should be triggered.

E.g. take this schematic as a reference: http://www.ucapps.de/mbhp/button_duoled_matrix.pdf

Take a cable and connect it with D0 of DEFAULT_SRM_DIN_L and D7 of DEFAULT_SRM_DOUT_CATHODES1 -> do you get a single MIDI event, or multiple events?

Try also other pin combinations.

Best Regards, Thorsten.

It didnt worked, as you described. …

By luck two friends from India came by (one hardware - && one software specialist) and we looked together at the circuit.

Their opinion was that the DOUT module couldn’t work without the serial resistors connected, which I didnt solder on the board - because of the following description from this schematics

“NOTE: the 220 Ohm Resistors on the two DEFAULT_SRM_DOUT_CATHODES* Registers should be removed.”

I dont know if I completely misunderstood these words, but when we tested with exactly the same configuration with a DOUT module with all four 220Ohm resistor networks connected everything worked fine…

So, finally “everything” is working - I will just finish and then post a little picture..

!!! THANKS EVERYBODY FOR YOUR TIME AND HELP !!!

you are great. ucapps is great. midibox is great. TK. is great!

Oh my god! Thanks for the eye opener! :-/

Of course, instead of “220 Ohm resistors can be removed” actually I meant “220 Ohm resistors can be replaced by cables” - I corrected this in the schematic.

I’m sorry for the trouble!

Best Regards, Thorsten.