The Dub Master MIDIbox 64 -work in progress-

MIDIbox HUIs
1

UPDATE: 08-05-08

Title has been updated from “Want t make a Midibox 64, need guidance.”,

to "The Dub Master MIDIbox 64 -work in progress-

New post showing some pics of my progress.

Hello again people!

As im waiting for my MIDIbox SID parts,

im looking at the ucapps site.

Iv’e decided that the MIDIbox 64 is the right midi controller for me.

Im reading:

“It is extremely expandable, you can use it as low-cost controller without display or buttons with just 8 or 16 pots (see here), or you can build a full-featured controller with LCD, 64 pots/faders, 64 buttons, 64 LEDs, a lot of BankSticks for using external banks”

Are these the only options?

All i need and want is 64 control elements (faders) together with full bankstick configuration,

LTC for midi activity and midi thru option, and a LCD display.

In this case i would only need a LCD, a Core with a PIC18F452, two AIN’s and a LTC.

Would this configuration work?

Also, for the banksticks.

24LC256 or 24LC512?

2

Ok so i went for the full setup anyway..

Though i noticed something…

When ordering the parts for the MB64 i looked at this schematic:

I just realized i forgott to order a third DIN kit..

It’s not included in the schematic, but you still need one for the LCD right?

I didn’t even think of because of this picture. cr*p… :stuck_out_tongue:

mbhp_midibox64.gif
mbhp_midibox64.gif621×627 11 KB

3

you don’t need a din for the lcd - there is a dedicated socket for the lcd.

4

DIN = D igital IN put. An LC display displays stuff, which means it’s OUTput, so I don’t really know what gave you the idea you needed a DIN board for it :wink: As matrigs already correctly pointed out, you don’t need anything else to connect an LCD.

5

…well..when i ordered the parts for the MB SID v2 i read everything on this page:

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

I added a DIN module for that order..

“It consists of a 2x20 LCD, 9 buttons and one rotary encoder, accordingly 11 digital inputs of a MBHP_DIN module are required. You can either etch a DINX2 module by yourself (2 shift registers provide 16 inputs), you can build the circuit on a veroboard (e.g. the same one on which the parts are mounted), or you can buy a premade DINX4 board, where you only need to stuff the two first shift registers.”

Bur reading your posts…and reading the quote i inserted here…

i now understand that these DIN modules are for the buttons..

I feel like such an ass…geez..  :-[  :-[  :-[

and the really sad thing is…i had just enough time to order a another DIN

module from SmashTV before i saw your posts… :cry:

aw maaan…just looking at the picture I linked to above…

How could i miss all of this information?!?!

6

*knowledge is power*

now you are doomed to do something with it, buy another core, forget something else, buy it again and over and over again

welcome aboard

simone

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now you are doomed to do something with it, buy another core, forget something else, buy it again and over and over again

welcome aboard

simone

Thanx Cimo! :smiley:

Well i had time to stop it and i got a refund.

Thank you SmashTV for your incredible fast reply!

regarding my “tag”…

Thats why it’s so embarrassing  :-[

EDIT-ADD-

Regarding the buttons.

Would these do the job?

Here are the specs

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..they will do a nice job for you!

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They appear to be what a lot of people (including myself) use, since they’re fairly reliable, very cheap and widely available.

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Those where the answers i was hoping for.

Thanx guys!

EDIT>

Do you guys use linear or logarithmic pots?

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lin.

log only for audio signals.

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Of course it is…

Cr*p..

I gotta do something about my very short memory :-\

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I gotta do something about my very short memory :-\

… take it easy. When you’re new to this stuff, there is so much information to stuff into your head. - At the moment you think you got it all, and then you suddenly miss pieces again. - Good luck with your box.

Greets, Roger

14

I have a shocking memory. I’m sure Twin-X will have logs that show that I run more searches and refer to more documentation than anyone - it’s because I can’t remember squat!  :wink:

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hehe, thanx guys :slight_smile:

16

Damn..

Looks like i got a another gig, and it will happen in like less than 2 weeks!!

So there’s a bit of panic over here. I gotta finish my MB64 in time for it.

Problem is, wallet is thin so i can’t buy those highly needed 10K pots.

I do however have a buch of other values at home.

Anyone here ever used other values for their MB64 controllers?

Im wondering, whats the highest value i could use?

47K, 100K?

<edit>

I searched the wiki and discovered that some manufacturers mark potentiometers like this:

A=logarithmic and B=linear

And that other manufacturers mark their potentiometers like this:

A=linear and B=logarithmic

I also read that measuring the pots is the best way to find out, wether it’s a linear or a logarithmic pot.

At the half way point’ date=’ a 10K [b’]linear pot will measure 5K ohms.

At the half way point, a logarithmic pot will either measure 6.5K ohms,

(approx) or 3.5K ohms (depending on which side of the pot you are testing).

When you put one probe on the center pin, and the other on one of the outer pins.

This may be obvious for some people, but it had me confused for ages!â€

Turns out that my pots have been marked like this:

A=linear and B=logarithmic

So i doo have the pots for my projects.

But im still wondering if any other values might work?

I do however have a question regardning the PSU.

I have aregular 9V 500mA wallwart here.

But it’s only 15VA. Would this suffice?

17

I never got an answer to this, and i havent found the answer in the wiki.

I might be blind on the other hand.

I still want to know..

Is there any other value on the pots (instead of 10K) that could be used in the MB projects?

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Is there any other value on the pots (instead of 10K) that could be used in the MB projects?

10k is very highly recomended.

Others can work, but too high a value is a bad thing, as it creates jitter (noise) on the AIN pin, which the core is duty-bound to process and spit out as a string of MIDI values.

Too low a value can put extra strain on your PSU, leading to the inevitable posts of "my core keeps resetting, I have 64 100 ohm pots and a 25uA power supply. What is wrong? ;D

19

i seeeeeeeeeeeeeee  :o

well, lets talk specualtive.

If one…decided to use pots with a high value…then this would cause jitter..

I know it’s not recomended…but bare with me.

How would one compensate for the jitter?

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depending on what value of pots you use… you can compensate for the jitter with a filter capacitor for every pot…  there’s a formula for figuring out what value of capacitor you should use but i’m going to have to search a little while to find it.  hopefully that will get you started! ;D