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I'm proud to announce the MidiBox-TIA !



Hi everyone I'm proud to present the MidiBox TIA Cartridge!


This is the first FULL midi synthetizer based on the TIA chip and cartridge cased.

This is a DIY project, the firmware is opensource.


It was not easy. Not because of the technical issues, just bad karma.

In 2011/2012 I made a working firmware and a manager under Max/MSP.

Because of personal reasons, I put the project on hold.


End of 2012, I received a message from Eptheca who asked me the status of the project.

With his help we decided to print 3 PCB’s. Unfortunately during this period, the hard drive of my computer suddenly decided to leave me, and I lost all my work: ((

I sent the drive to Shanghai to try to recover my data, but of course my disc was one of the non-recoverable 10% (always this bad karma).


So now we had the box and the electronics but nothing to put in it.

In February I decided to rewrite everything but it took me some time.




We've now got a new firmware and the application to manage the box.


I am inspired by the version 1 MB-SID.

I kept all the features of this engine.


I improved the management of banks, I dedicated two envelopes to the voice of the TIA which is free, and a few small details that might please you.


Here is the features of it:

  • 1 dedicated envelope for each voices(so 2) with optional non-linear curve and Sync which can be assigned to Amplitude and pitch. 3 specifics Mode to mix Modulation matrix and this env
    Env+Mods, Env*Mods, Env+(Env*Mods).
  • 2 additional envelopes with optional non-linear curve and Sync which can be assigned to Amplitude and pitch.
  • 4 additional LFOs with different waveforms and Sync which can be assigned to Amplitude and pitch.
  • Pitch Bender
  • Portamento/Glide function with Optional "Constant Time Slide".
  • Delays
  • 1 Arpeggiator for each voice(so 2) with optional Sync.
  • Poly, Mono and Legato Mode
  • Separate keyboard zones for each voice (key splitting) allows to play voices separately
  • Extended Mode for keys(all note reponse) or non extended with offset and length.
  • 1 velocity response for each voices (so 2) with optional CC assignment
  • Free controller assignments to Modulation Wheel and Aftertouch
  • LFOs, Envelopes, Arpeggios optionally syncable via external MIDI clock (one for each;)
  • Bankstick support (4 banks of 128 sound patches per stick, up to 8 can be connected) so 32 banks.
  • And much more.

Coming soon:

  • wave and CC sequences which allow more percussive sounds (Wavetables) with dedicated banks.
  • Drum or Fx Kit Presets with dedicated banks.
  • 8 Analog I/O
  • 4bit sampling ;)
  • Atari 2600 Joystick and Video touch pad support.

IMG 0215 2


There's no CS on the cartridge version, but there's enough room in FW to add it. If someone wants to create it, you are welcome. This firmware is only for 18f4685.


You can add MB-Link too if you need it, PORTA.0-7 and PORTB.0-3 share 8 I/O on the AUX connector.


No CS; but I designed a Max/MSP Application (windows and Mac compatible):

MidiBox-TIA Standalone Manager



And it has iDevice support(sorry for those who boycott Apple products):

MidiBox-TIA iOS surface control



I'm trying to finish a Max4Live version, with a common file between both applications that will retrieve the names of banks, patches and all parameters without having to open the input of the midi track and make a CC request (there's no SysEx in Ableton Live).


Now i suppose you want to hear it:



Voilà!!! smile.png


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I'm trying to understand what you have done. The TIA's musical abilities are less than spectacular - mostly due to the limited frequencies provided by the 5 bit frequency divisor. So what would be the point in controlling it via MIDI (unless you want to use it as a part of a "chip tune" piece)?

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You question my reasons to make midi control of the TIA, since it's not a perfect "synthesizer" sound source.

You refer to the limited frequencies etc.

I guess what you means is that it doesn't have a perfect pitched scale across all the frequencies, so you don't understand why i control it by midi


You says :So what would be the point......


The point is it's fun, i can do it, it sounds great, it has a unique sound, i can use and control those sounds with a DAW like Live for making music

You think it could only be useful for making chip-tunes/8-bit music, that's a limited horizon


I love the sounds of sound chips and game controllers from the 70/80/90's but I don't make (or particularly like) video game music

I make techno (minimal) and find the sounds from these sound sources are perfect for that

And I love all the electronics and soldering and building and engineering etc.


So... I'm not a game programmer, I'm just a passionate musician electronics, traumatized by the sound of the game console of his childhood.

Sorry but this is a bit like if I asked you why continue to create games on a console with graphics capability which are totally old fashioned. But I do not do it because I understand and respect that ;)


Best regards

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Completely reasonable answer. You want to make music which sounds like it was made by a 2600, so you've made a MIDI controlled TIA.


My disconnect was if you made this expecting to get anything sounding like standard pitches. Or if you weren't prepared to work within the limited boundaries of the TIA.


Does your software allow for more complex sounds than simply playing the different AUDC/AUDF combinations? i.e. "envelopes" which change the TIA registers automatically.


Note: for people who just want to play AUDC/AUDF on a synth, I did a set of WAV file samples: http://atariage.com/...0/#entry2127668

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Good question! Now we can speak seriously hihi.


'My' software(Firmware) is a MIOS8 (Midibox Operating System 8bit) based program written in ASM, the uC which replace the old MOS is a PIC18F4685 (Microchip 8bits family). http://www.ucapps.de/ http://midibox.org.

You're right, it's more than pushing values in AUDV/AUDF on each Midi Note. There's a software engine between midi and TIA, which allow more complex sounds, due to it we've got a lot of modulation and effect capabilities on each voices (Aud0/Aud1;).

I have now dedicated portamento (pitch slide between 2 notes), an internal 4 notes arpeggiator with Midi Clock Sync Option to respect an external song tempo, delay, transpose and many more options.

Envelopes adds dynamic to amplitude or pitch .It's real envs with Attack, Decay, Sustain, Release, and assignable curve bender.

There's 4 Low Frequency Oscillators and 2 additional envelopes (Midi clock sync too) which are assignable to amplitude or pitch via a Matrix.

Of course... Each voice responds to keyboard velocity or aftertouch

Here is the list of controllers (CC#):


You can store every parameters on an external or internal eeprom (32 banks of 128 presets) named bankStick and it's hot-swappable... Can communicate with it via System Exclusive, to send/request banks/presets, and archive and share with other people.


And it's not finished...

This is the second time i write it cause i lost the first one, the latter was more advanced (+wavetable, sampling)...


Do you know Wavetables? This consist in a list of rapid changes(in ms) on CC# like pitch slide or/and different waveform in the same sound, to obtain structured sound like Drums. Very good for percussion.

In a slow rate it can be a sequencer like the old music trackers.

I recorded a drum kit example, it's still on soundcloud(http://snd.sc/19GDPDH), and i had not really dig it deeply.


Sampling in 4 or 5 bits... it is an idea of a member in the midibox forum, I did not know that this technique was used on the 2600, and it's here that I learned to apply it. This resulted in a really interesting LoFi sound . Elsewhere! the first thing it was able to sing was : "Have you play Atari today";) I used this sample throughout my test...

I will also rewrite this part in the next firmware version.



And i will continue to explore this chip, in life i'm an audiovisual technician and i haven't forget that there's a video and interactive part inside it. I've thought about and tested another project based on the TIA, always for real-time creating. I am also owner of a C240 ;)


...Ohhhh! want to remind, it's open-source and I share all my work!

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Bumping this cause I didn't find it till now, GREAT WORK!!

Fantastic demos, the TIA never sounded so good!!


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