MIDIbox 808 Firmware

[TK.]

I wrote down my thoughts on the MB808 firmware. Since it's mainly directed to people who already own a MB808 PCB, the discussion is started in the eight-oh-eight forum: http://eight-oh-eight.org/phpbb2/viewtopic.php?p=2047

Note that this application will be useful as low-cost and easy-to-built MIDI drum machine as well!

But primary focus is to get the max out of the beautiful MB808 :)

(I locked this "link article" to avoid multiple threads about the same topic)

Unlocked article, since v1.0 has been reached

Best Regards, Thorsten.

[TK.]

I wrote down a draft spec here:

http://www.ucapps.de/midibox_808.html

Please let me know, if anything is missing, or if you see additional requirements, before I'm starting with the implementation (it will be started soon :))

Best Regards, Thorsten.

[TK.]

The first beta version can be downloaded from the bottom of this page (press refresh button of your browser if you don't see the .zip package): http://www.ucapps.de/midibox808.html

It's already working quite stable, and I had some fun with it.

You *must* try out this:

- press&hold EDIT button

- select LC/MC/HC tracks

- change to random page with ALT+GP button 12

- press one of the GP buttons to generate random patterns until it sounds nice

- change to progression page with ALT+GP button 7

- press GP button 5 (Fwd: 5) and 11 (JBack: 3)

- enjoy the sequence, and don't forget to switch between A and B section 

MIDIbox SEQ V3 users who want to evaluate the firmware can upload the setup_808_mbseqv3_hardware.hex firmware. The default pattern setup outputs MIDI events at Channel #10 (General MIDI drum map is used)

Please read the warning about Mixer BankSticks if your one isn't connected to CS2!

Best Regards, Thorsten.

[TK.]

MB808 v1.0 has been released "by accident" last sunday (during the re-release of all MIOS applications).

However, it works very stable since weeks, all planned features are implemented - have fun! :)

Best Regards, Thorsten.

[Sasha]

I am making standalone sequencer for external drum machine and have one question... does Accent track works only with MB808 or it affects Velocity of notes sent at MIDI out.

[TK.]

Both (it also affects MIDI notes)

Best Regards, Thorsten.

[Sasha]

Cool. Thank you Thorsten.

[Sasha]

I`ve been playing with this nice sequencer triggering Reason`s ReDrum and thought it would be very useful if instrument encoder can be used for sending program change when using with software drum machines. BPM LED display is sufficient to display the PC number with additional LED that signals it showing BPM or PC. One button can be used for switching the display view. Somebody in the mood to do the code modification?  :)

I`m having good progress with PCBs for integrated standalone drum sequencer and I`m pretty satisfied with the results by far. I think that feature would make it much useful when using with software based drum machines as you don`t need to look at the screen.

[Alain6870]

Hello Torsten and the other MB gurus,

Thank you for your piece of Software. It is so cool...

I've finished my MB808 last night and could play with it for some hours. Except a small Hardware problem with my leds everything is ok and it was only pleasure: tchak tchak boom!

I noticed when playing in song mode with a 32' scale and a 12 steps length (for all the pattern) that this pattern was then repeated untill 1 measure was reach before it jumped to the next pattern. Is this intend or did I miss something? Maybe the steps are always given in 16' scale (quarter note), I don't know! What I explained is a little bit embarrassing when you want to play a fill in for a song and it doesnt exactly match one measure or for special rhythmic scale ie (7/8 beat etc...).

Sorry for being not so clear. Let me know if what I wrote is really not understandable, and thank you for your patience.

[TK.]

In song mode the reference measure for synching pattern changes is always 16 * 16th notes, so it works like intended.

In newer MBSEQ V3 releases, the number of "reference steps" can be selected between 1..256, but this won't cover your usecase, as this is a global setting, which will be used for all pattern changes.

To be honest: I don't know how to solve your request! There are different step lengths possible for all 16 tracks, how should the firmware determine the intended pattern length without limiting existing possibilities? (e.g. playing 8 step tracks 2 times before changing to the next pattern?)

Best Regards, Thorsten.

[Alain6870]

Hello Torsten,

Yes your suggestion would fullfill my expectations in most cases. For instance when I have a song written in 3/4 I can programm the patterns or the tracks in every timebase I want and finally indicate the sequencer that for this song chaning has to occur every 12 of 16th steps.

Even further ,it would be cool to have a dedicated timebase for the pattern chaning in song mode, it could be then more accurate.  IE: Song Timebase 8 and chaning_steps 7 for instance.

For my other problem with the fill_in pattern I could let some rest to adapt the pattern to the overall duration.

kind regards,

[TK.]

MB808 V1.1 now supports a configurable number of steps per measure:

http://www.ucapps.de/midibox_808_changelog.html

Best Regards, Thorsten.

[nebula]

I`ve been playing with this nice sequencer triggering Reason`s ReDrum and thought it would be very useful if instrument encoder can be used for sending program change when using with software drum machines. BPM LED display is sufficient to display the PC number with additional LED that signals it showing BPM or PC. One button can be used for switching the display view. Somebody in the mood to do the code modification?  :)

I`m having good progress with PCBs for integrated standalone drum sequencer and I`m pretty satisfied with the results by far. I think that feature would make it much useful when using with software based drum machines as you don`t need to look at the screen.

My apologies if this has been implemented already, since I have not built an MB808,  but I just had a thought:

A good way to implement this would be to hold down a "program change" button, which toggles the display and turn the encoder. While turning the encoder the program change appears on the LED display, but it is not sent until you release the button.  Maybe then the display could quickly blink to indicate it was sent, then switch back to BPM.  Reason: some drum machines and grooveboxes load big banks of samples on every program change, so you don't want a program change sent every time the encoder "clicks".  Also: an additional LED would not be required, because you already know you're in "program change" view, since you're holding down a button.

[Alain6870]

Hello Thorsten,

First of all I want to apologize for the misspelling of your name, in my last mail I forgot the h after the t. This simple ommission is due to the fact that I know some Torsten too, as you know in Germany both are usual with and without the h. But let's go to the subject...

I tested the new version of the soft and it rocks. V1.1 is ok with the added menu for step length in song mode. it's exactly what i wanted.

Thank you for your very quick update.

I noticed a minor "bug" in the display of the timebase menu. Whe you display the string "Sync to bar:" and then go back to an other menu that displays the string "Selection: " you have as a result the message "Selection:r". So I changed the length of the string "Selection" in the source Cs_m_trkdiv.inc and now everything is ok. I presume you could change this with the next update.

Grüsse,

Best Regards,

[TK.]

Thank you! :)

The change is now in the code repository, so that it doesn't get lost.

Best Regards, Thorsten.

[Antix]

Hi,

i'm looking trough the site to understand how can i trig drum generator circuits with a 808 firmware programmed core and DOUT.

i can't find schematics.

On 808 forum core schematics seems incomplete.

Maybe schematics are under my nose but i can see them?

If it is possible please help me.

regards

[strophlex]

Hi,

i'm looking trough the site to understand how can i trig drum generator circuits with a 808 firmware programmed core and DOUT.

i can't find schematics.

On 808 forum core schematics seems incomplete.

Maybe schematics are under my nose but i can see them?

If it is possible please help me.

regards

Here, under download, you can find the schematic for the core module

http://ucapps.de/mbhp_core.html

and here, under download, is several variations of the schematic for the dout module

http://ucapps.de/mbhp_dout.html

Hope that helps!

[Antix]

Thank You Strophlex,

but that is already clear.

i mean for example:

bassdrum trigger input in what DOUT output pin have to be connected ?

Is it the same of trigger led?

I can't understand with 808 forum schematics because it seems incomplete.

That is my problem.

I dont know where phisically i have to connect trigger inputs because

i dont read on the schematics ( or simply dont find it ).

Regards

[strophlex]

Take a look at this thread:

I think it is what you are looking for. Also, I don't think this is the proper thread for this discussion. We should use the above mentioned thread instead.

Good luck!

[electronicpresskit]

First off, thanks to TK! Sequencing the MB-808 is great!

I have two feature requests with the second being most fun:

Feature #1: Tempo Fine Control

hold down shift while adjusting the tempo encoder to get sub 1 bpm adjustments. I'm not sure what the right resolution would be, maybe .05 bpm per encoder click?

Feature #2: Momentary Tempo Adjust

hold down alt while adjusting the tempo encoder to make temporary tempo adjustments that snap back to the predefined tempo on release of alt. I think maybe .33 or .5 bpm per encoder click would be a good resolution? This provides a way to beat match similar to how DJ's push and pull the platter on a turntable.

I added these features to the software sequencer I make and it's really a lot of fun! It makes it easy to forget about midi beat clock and just go drop in on a friends DJ set or whatever. I'd love to have this on my MB-808! :)

[grizz]

I have a few questions about my MB808...

1. My instrument selection encoder is incredibly jumpy, and is really hard to select the correct instrument. I'm using the encoder that came with the Version 2 PCB's. Is there something that I can change in the ASM file?

2. I would like to use my 9090 with the MB808 sequencer. I can't find any info about the default channel for the output. Is it channel 10 like the MIDI in? I'm sure the information is documented somewhere obvious, but I simply can't find it.

3. I've noticed there has been a lot of talk about people wanting to use their 9090 with the MB808, and I'm wondering if anyone has changed the 808 firmware to accommodate some of the differences between the 909 and the 808?

As a feature request I'd like to suggest a separate page for sequencing the 9090... That would be pretty cool. Would it even be possible?

Cheers,

grizz

[nuke]

1. there are 4 encoder modes for detended encoders.

you could try to change "MIOS_ENC_MODE_DETENTED2" to "...DETENDED1 or 3 or 4...just look in the asm, it´s line 416 and 417.

there´s also a note about these modes.

2. it´s ch. 10 as default...but can easily be changed to any channel and note u like.

just enter the midi-page (alt+GP15), there u can select the notenumber and with holding shift it changes the channel of the corresponding instrument.

3. it´s not really necessary to change the firmware for the 909. unless you need the correct names for the selected instrument.

from the hardwareside you can use the trigger (not midi) to trigger the 909 but the accent circuit is different compared to the 808. The accent won´t work with the 909, therefore the circuit should be modified. but to trigger from midi is no problem so far.

As a feature request I'd like to suggest a separate page for sequencing the 9090... That would be pretty cool. Would it even be possible?

i guess not, since the pic is very limited in codespace...and allready nearly fullpacked...i guess no space for xtra tracks...

greets, nik

[sneakthief]

I have a few questions about my MB808...

1. My instrument selection encoder is incredibly jumpy, and is really hard to select the correct instrument. I'm using the encoder that came with the Version 2 PCB's. Is there something that I can change in the ASM file?

I have a batch 2 kit and no encoder came with it ...I thought those were ordered separately. Which one do you have?

I agree with Nuke's assessment that you should recompile the firmware with different encoder settings.

[sneakthief]

During playback, how do you configure the MB-808 so it switches A/B/C/D sections or patterns (when selected by hand) at the *end* of a bar and not immediately?

I tried various SPM settings with no luck.

[TK.]

You are right, the selected sections are copied into SEQ_SELECTED_ABCD and played immediately.

A synchronization mechanism isn't implemented, but it should be so difficult to add this.

It's now in the Wishlist: http://svnmios.midibox.org/filedetails.php?repname=svn.mios&path=%2Ftrunk%2Fapps%2Fsequencers%2Fmidibox_808%2FCHANGELOG.txt

Any other (simple to implement) feature request?

Best Regards, Thorsten.