d8b as MCU Controller 24 channels

[munkustrap]

Hi

I just want to let you know that I'm working on a new d8B MCU converter (24 Tracks) with a new approach.
I want to use a microcontroller STM32 as translator, which also keeps the firmware of the d8b console.
Target is, to connect that via USB to cubase and set upt cubase to the new Mackie MCU USB controller plus 2 extensions.
Benefit should be that the translation is done not on the PC but externally on the MC wit about 167MHz.
The virtual USB Midi port supports 4 connections. 3 are used for the MCUs + extensions. The 4. is planned to use for an additional display for each channel. I will post more information in the next weeks.

Till now I have build in the power supplys (fanless) as I have only the console and not the CPU. And I've cleaned the fader as I had a lot of sticky faders. $ faders I have changed to new ones (yamaha 01V96 spare part faders).
I can upload the firmware to the d8b console and can control Leds, scan switches, meters and so on. All commands for leds and switches vpots and faders are now engineered. Does anybody knows the command to clear the display and set the cursor to the first character?

best regards

[bitSync]

...Does anybody knows the command to clear the display and set the cursor to the first character?

Based on the MCU MIDI SysEx alone, the two lines of the VFD are "cleared" by writing ASCII spaces (0x20) to each of the character cells and there is no cursor positioning, per se. In the MIDI SysEx VFD messages there are 2 arguments, the first is an offset from the top line first character of the 2-line display, the second is the ASCII string itself. I don't have any information on the equivalent serial command from the d8b software. You'd have to sniff the serial command on the data interface between the CPU and the control surface. I don't know if you mean you really don't have the CPU or you're just not using it in your implementation.

A specification very similar (not identical) to the Mackie Control Protocol (MCP) can be found here -
http://stash.reaper.fm/v/2063/LogicControl_EN.pdf
The LCD (VFD for the d8b) syntax can be found on page 114.

There's a little bit of info on sniffing the serial interface between the CPU and the control surface here on the D8Bridge board -
http://www.d8bforum.com/phpBB3/viewtopic.php?f=6&t=634&start=70#p6878

A few posts further down there's some video of the streaming serial data to the d8b control surface captured with HyperTerminal.

[munkustrap]

Hi bitsync

thanks for the information and the links. This was also my first thought. I was just asking if somebody knows something more comfotable to handle, but it seems so mackie has not implemented something like that.

Yes I have NO CPU/PSU, only the console. Thats why I build in an own supply (5V/20A, 12V/10A, +/-16V, 2A) without fans .
the supply is build into the console. The microcontroller will also be build into the console but can also be used outside.

As I wrote I am able to transmit the console firmware and communicate with the console. Sending a "z" clears the display but then it doesn't react any more.

I will let you all updated about my process (in future with pictures and videos). I think it will be a good solution to have the time critical translation code on a microcontroller (hardware:STM32F4 discovery board) as no OS will disturb the realtime operations.

By the way: maybe interesting for all that have problems with the d8b.
Power supply design:
5V supply for digital and Leds
12V for faders AND additional regulators down to 5V for reference voltages for ADCs.
+/-16V for OPAMPs mainly Audio, but also Fader moving circuits OPAMPs.

Attention: the Motors of the Faders have an own Grounding that is tied to digital GND via the case of the console.

best regards
Ralph

[munkustrap]

Thats the uC board I will use:
costs less than 20 $

http://www.st.com/web/catalog/tools/FM116/SC959/SS1532/PF252419

It will make the translation and the control of the additional LCDs (96x48 pixels) for each channel.
Today I found a good methode to attach the additional channel displays without sawing the front plate

[bitSync]

...By the way: maybe interesting for all that have problems with the d8b.
Power supply design:
5V supply for digital and Leds
12V for faders AND additional regulators down to 5V for reference voltages for ADCs.
+/-16V for OPAMPs mainly Audio, but also Fader moving circuits OPAMPs.

Ralph,

Do you have any idea about the DC current requirements for those voltages? Thanks.

[munkustrap]

Yes,
5V needs 20Ampere
12V I measured 4,5A when All faders moving.
Take a 7Ampere to be on the save side.
+-16V I'm Not sure. The Lm315 can Do 3ampere but its
Getting Very hot with about 2ampere With heat sink. But this is also used in the original Psu. I will measure that again.
Best regards.

[bitSync]

Yes,
5V needs 20Ampere
12V I measured 4,5A when All faders moving.
Take a 7Ampere to be on the save side.
+-16V I'm Not sure. The Lm315 can Do 3ampere but its
Getting Very hot with about 2ampere With heat sink. But this is also used in the original Psu. I will measure that again.
Best regards.

Was the 20A 5VDC from a measurement? Thank you very much!

[munkustrap]

No, its in the Service Manual. But only the 5v 20A.

[system32]

Are you 100% sure 5v needs 20A ?

[anyhorizon]

You sure there isn't a period between the 2 and the 0?

Peter