Multiplexing 8 analog inputs using a CD4051B

[sidetrakd]

It wasn't that difficult at all but it really helped having someone who knows what he's at do the firmware.He says it was pretty simple and you have everything well documented!
Having him there though to help with bugs and make changes as i thought of them really made a huge difference!!
I would definitely say have a go at it! It really seemed harder than it was and now i have a custom controller with amazing capabilities!!
I will be doing a build log when i get some spare time,hopefully that will help others!

[MiL0]

that's amazing - really shows the potential for the midifighter to be used as a midi 'brain' for more complex projects... nice one

looking forward to a parts list, some code and/or a blog/instructions guide!

[notshy]

sneak peek

4 multiplexers for 32 analog inputs, 12 for knobs/faders (4 not connected) and 20 for buttons assigned as follows:

• 4 bank buttons (rigged up to the midifighter external bank code)
• 4 buttons (the black ones on the left) are used as "global" banks and change the midi channel for all other buttons
• 1 input used for a foot pedal
• The rest are used as general buttons (only 5 are connected)

For the analog buttons, I check the ADC value against a threshold to see if it is pushed or not (with some crude transition detection code).

LEDs are driven by a PIC, connected to the digital pins over something almost SPI (3 pins are shared with the multiplexers, the spare is used as slave select). This gives me num_pic_io - 4 LED's (17 for my 21 I/O pin PIC): green LEDs on the bank and global bank buttons, blue on the other five buttons.

The global banks are used to select the midi channel, so the buttons always have the same notes, just on a different channel.

More details & pics when I get time to write up a build log.

Wooh - sick mod ! I'd be keen to get stuck into something like this !

Good work .

[sidetrakd]

that's amazing - really shows the potential for the midifighter to be used as a midi 'brain' for more complex projects... nice one

looking forward to a parts list, some code and/or a blog/instructions guide!

The project took up most of my spare time but i will do a write up with pics and maybe a demo video as soon as i get a few final bugs fixed(and find some time)

[bderewic]

I cant wait to see this, i have been drafting up MF custom designs (lots), and researching how i can mod out the MF to make all my controls work.

Came across this thread ..... awesome, ill be working one of these soon enough, im looking to do 24 buttons, 2 faders 2 scroll/push pots and a jog wheel type device using an optical encoder.... i

[sidetrakd]

might have a little hold up on this
went to flash the midifighter and all the led's lit up like a christmas tree
seems like a pcb fail will not flash no matter what i try
And it was just about ready..Was gonna road test it at a gig on the 23rd!

[Fatlimey]

Assuming you are using a PC, did you follow all the instructions on the DFU reflash page? When you knock the Midifighter into bootloader mode using the Boot/Reset keys on the PCB it enumerates over USB as a different kind of device, one that requires a driver to be loaded on the main computer to be recognized.

Did you install the Midifigher DFU Bootloader driver? Do that, then try the Boot/Reset key technique to drop into Bootloader mode (there will be no indication from the Midifighter that this has been successful) then try a reflash using Atmel Flip.

We have recently worked out what this recurring fault is and have a solution for all new Midifighters, but it's a little technical...

[sidetrakd]

Assuming you are using a PC, did you follow all the instructions on the DFU reflash page? When you knock the Midifighter into bootloader mode using the Boot/Reset keys on the PCB it enumerates over USB as a different kind of device, one that requires a driver to be loaded on the main computer to be recognized.

Did you install the Midifigher DFU Bootloader driver? Do that, then try the Boot/Reset key technique to drop into Bootloader mode (there will be no indication from the Midifighter that this has been successful) then try a reflash using Atmel Flip.
.

The DFU driver installed previously,since the problem I just get "Unrecognised USB Device"
Atmel Filp just goes to "Could not open USB Device"

We have recently worked out what this recurring fault is and have a solution for all new Midifighters, but it's a little technical...

"A little technical..." sounds great compared to switching the atmel chip for a new one which was gonna be my weekend project if you had no other solution
:eek: :eek:

Thanks for your help!!
Have I mentoned yet that I've never done anything like this before?Luckily Im a fast learner and the internet is a good teacher!!

[sidetrakd]

Anyone following my project check this out

http://www.djtechtools.com/forum/showthread.php?t=28014

Had an hour last night to put up a few pics in a new thread (midifighter not working is giving me a little time!!)

[sidetrakd]

We have recently worked out what this recurring fault is and have a solution for all new Midifighters, but it's a little technical...

Fatlimey could you shine a light on this for me?Is the problem with the atmel chip or is it somewhere else?Nothing i do is bringing it back to life.I have a spare atmel chip here just incase.