MIDIBOX LC & Led Meters

[Guest STephenTi]

Hi all !

Another test for me, with the led meters this time.

I've connect the 12x8 led like shown in the documentation.

My host is Cubase SX and the Midibox LC works in Mackie control emulation.

When I start Cubase with a track (for exemple track 1), all the leds are working very strangely (don't know if this word exists !).

With volume set to 0, no led. Ok

But if I increase the volume, the leds working change (track 8 is low level, then track 8 + 7, then track 7, and so on..., then track 1 and if upper, track 8 again !).

It's look as if the led meter number (WREG in LC_METERS_PatternSet ?) depends on the volume of the track and/or the level of the corresponding fader...

This is very beautiful, but not very usefull as led meter ! :)

Does somebody have the led meters working with his Midibox LC  or maybe this function is still beta (I'm ready for all your tests !)

Thanks !

[TK.]

Hi Stephan,

this function isn't beta, it works fine with Logic Audio.

Could it be that you've enabled the common LED Meters function of Cubase which doesn't match with the LC Protocol? If there is no alternative option, possibly a new LC_METERS pattern has to be programmed especially for Cubase

Best Regards, Thorsten.

[Guest STephenTi]

Thanks...

I'm very interrested in trying to help you for the program ! But it's really hard to understand how works the LC_METERS pattern. It's in the files lc_meter_icons_h.inc and lc_meter_icons_v.inc ?

[Steven_C]

yes, strangely is an english word! ;)

[TK.]

> It's in the files lc_meter_icons_h.inc and lc_meter_icons_v.inc

no, these are the icons for the graphical display.

Just one question before: are the meters displayed correctly when you switch to display page 1 (or 2, don't remember which page...). You can switch to this page with the appr. Special Function button, or you can set it as default page in main.asm (INITIAL_DISPLAY_PAGE)

Best Regards, Thorsten.

[Guest STephenTi]

Hi Thorsten

I'll try this today and I tell you...

I've make some test last night. I modify the lc_mproc.inc to display on the first LDC the 8 bits or MIOS_PARAMETER2 in LC_MPROC_Received_D0 function. I want to check if the midi message send by Cubase looks like "0hhhllll" (your description in the lc_mproc.inc).

I don't know if this test is good but the 8 bits seems to be used only for the meter level (I don't see any information about the channel). It's look like a master level...

Do you have any description of the Mackie midi protocole with Cubase ?

::) I was very happy when the 8 bits of MIOS_PARAMETER2 appears in the LCD ! It was my first personal code for a PIC  :)

[Guest STephenTi]

I've make the test.

With INITIAL_DISPLAY_PAGE set to 1, the LCD show the meters for each channel. But, sorry, the display is exactly the same as my led meters...

Example :

- I have just one audio track in my host.

- With level set in my host to 0 : nothing displayed

- With low level : channel 1 display some leds, following the sound level

- If I increase the level, channel 2, and then 3, and so on, are displaying leds....

?!?

[TK.]

Hi,

from my point of view the results are perfect, because they demonstrate that Cubase doesn't send the metering data in the same format like documented in the Logic Control manual.

The manual can be found somewhere at the Emagic page. But since Cubase uses another format, this won't really help you.

So, I could possibly tell you which function has to be changed exatly if I would know how the format used by Cubase. Are you able to log the MIDI messages sent to your MBLC w/ MIDI-Ox?

Best Regards, Thorsten.

[Guest STephenTi]

I'll try this night to find a way to log midi activity from Cubase to Midibox... It's seems not so easy to do...

And I try to find the Midi implementation protocole for Mackie somewhere ...

May be somebody in this forum know somebody at Steinberg ? ...

[Guest STephenTi]

Hi all.

Some news about led meters for Mackie emulation/Cubase

- First, I have a response from a Logic Developer (Control Surface integration) and he tells me that the Mackie midi implementation for meters is the same as Logic Control.

- I've made a lots of test this week-end !

I've connect my computer midi out to midi IN, start MIDI-OX first and Cubase. Then, I can log Cubase's Midi Out activity.

I've note that for eatch meter info send, Cubase send 2 midi info (D0). The first looks like the Logic implementation.

The second seems to be a counter that decrease.

I've modify the lc_mproc.inc to ignore the second midi message. It's better !

I continue to search the reason of this second midi message ...

A extract from a log : (channel 1 & 5 are playing)

00139E6F   1  --     D0    08    --    1  ---  Channel Aft          

00139E70   1  --     D0    04    --    1  ---  Channel Aft          

00139E70   1  --     D0    48    --    1  ---  Channel Aft          

00139E71   1  --     D0    04    --    1  ---  Channel Aft          

00139E8C   1  --     D0    08    --    1  ---  Channel Aft          

00139E8C   1  --     D0    02    --    1  ---  Channel Aft          

00139E8D   1  --     D0    48    --    1  ---  Channel Aft          

00139E8F   1  --     D0    02    --    1  ---  Channel Aft          

00139EAC   1  --     D0    07    --    1  ---  Channel Aft          

00139EAF   1  --     D0    7F    --    1  ---  Channel Aft          

00139EB0   1  --     D0    47    --    1  ---  Channel Aft          

00139EB1   1  --     D0    7F    --    1  ---  Channel Aft          

00139ED0   1  --     D0    07    --    1  ---  Channel Aft          

00139ED1   1  --     D0    7D    --    1  ---  Channel Aft          

00139ED1   1  --     D0    47    --    1  ---  Channel Aft          

00139ED2   1  --     D0    7D    --    1  ---  Channel Aft          

00139EEC   1  --     D0    07    --    1  ---  Channel Aft          

00139EED   1  --     D0    7B    --    1  ---  Channel Aft          

00139EEF   1  --     D0    47    --    1  ---  Channel Aft          

00139EF0   1  --     D0    7B    --    1  ---  Channel Aft      

[TK.]

Very strange, this could be a bug in Cubase, no?

From the Emagic LC Manual:

Best Regards, Thorsten.

[Guest STephenTi]

Hi all.

I've make more trace to understand the object of the second midi message send for meters to Mackie control.

I think that the first midi message is similar to Logic protocol and the second upgrade meter precision to 12 bits.

Can somebody give me some help to modify the lc_mproc.asm to test :

- First to ignore the second message

- second, to use the 12 bits for meter level

Thanks.

[TK.]

Just to clarify if this is really true (sounds like a poor implementation from Steinberg if they violate the protocol and if they really use the same events for two different informations) - could you post a logfile with the metering information of a single channel? Sweep the volume from low to high to make the coding clear to me.

Dan, if you read this: did you notice the same effect with your MIDIbox LC?

Best Regards, Thorsten.

[Guest STephenTi]

Hello !

Here are 2 sample log :

- http://www.dotsoft.fr/stephenTi/midi.log Sample with track 1 playing, volume move from 0 to max and then to 0.

- http://www.dotsoft.fr/stephenTi/midi1.log Channels 1 and 5 playing and then stop button pressed.

I don't think my problem come from a Steinberg bug (I've update my version with the last patch). I'm very interrested with Cubase SX user's opinion !

Thanks.

[TK.]

Hi,

I didn't wrote that this is a Steinberg bug, I wrote that they violated the protocol. Or in other words: either they haven't read the specification and implemented the meters in the wrong way, or they thought that they could "enhance" the protocol, but did this in a very unusual and incompatible way.

The biggest problem with the Steinberg implementation: it's not fail-save. Means: there is no flag or something else which indicates the first and the second byte. This means that the protocol handler could get out of sync (e.g. during the startup phase or if the MIDI cables are temporary not connected). Something like a time-out mechanism could help here as a dirty workaround.

Second problem: they don't use the meter events in the same way like Logic. The emagic guys were clever, Logic sends only the peaks, and Logic Control decreases the meter level automatically:

MIDIbox LC decreases the meter levels also automatically (of course).

But from your logfiles it can be assumed that Cubase sends every single LED event. This costs a lot of bandwidth (means: motorfaders won't be moved in realtime, very slow LCD messages, etc...).

Third problem: I don't know why it would make sense to send LED meters with 7+4 = 11 bit resolution. Who really wants to have 2048 LEDs for a single meter? ;-)

Result: the implementation is very different from the original LC. Either you've misconfigured Cubase (a user wrote some time ago that Cubase provides some kind of generic metering via MIDI - hope that you haven't enabled it, because it wouldn't be compatible with MC/LC), or a special function for Cubase has to be programmed (without the automatic decrease and with a parser for this broken protocol). Of course, not a big problem with MIOS, but who wants to spent the effort?

Best Regards, Thorsten.

[Guest STephenTi]

Hi Thorsen.

Thanks for your response.

"Of course, not a big problem with MIOS, but who wants to spent the effort? "

Do you think it's difficult for a "newbie" like me ? It's the first time for me with PIC assembly but I work in IT (15 years) with other languages...

[TK.]

Hi,

since you are asking this, I would say: yes, it will be difficult.

However, once you've learned the most important assembly instructions and the programm execution flow of MIDIbox LC, you should be able to do this change.

A good starting point is the PIC18F452 datasheet, which can be downloaded from the Microchip Homepage. http://www.piclist.com provides some tips for common programming problems, the MIOS examples are always a good starting point to learn more about the interactions with the OS, and finally you can try to modify the MIDIbox LC code (step by step...)

Best Regards, Thorsten.