Minimal MIDI decoder

Designing hardware that uses VLSI Solution's devices as slave codecs such as an external MP3 decoder chip for a host microcontroller.
Davidelvig
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Minimal MIDI decoder

Post by Davidelvig » Wed 2015-11-11 8:28

I'm building a device using the Teensy board from pjrc.com, and have used both the Sparkfun and AdaFruit vs1053 breakout boards to play MIDI sent from that board.

I need a smaller form factor that the two breakout boards have. I only need:
- MIDI in
- WAV mixed in would be a bonus
- audio out... Headphone level would be best
- 3v3 power and logic level
- I want to talk to the MIDI player using a digital pin

I need:
1) a recommendation for the lowest cost VLSI chip that would do this
2) minimalist wiring diagram. How few pins can I use, including ground and power

Thanks.
Dave

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pasi
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Re: Minimal MIDI decoder

Post by pasi » Wed 2015-11-11 14:58

Is it MIDI from a file or realtime MIDI commands?
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Davidelvig
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Re: Minimal MIDI decoder

Post by Davidelvig » Wed 2015-11-11 16:31

MIDI commands. Not from files

Davidelvig
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Re: Minimal MIDI decoder

Post by Davidelvig » Fri 2015-11-13 18:34

I'm seeing several VLSI chips that have the word MIDI in their description.
Would the 1033 meet my needs
I only need:
- MIDI in
- WAV mixed in would be a bonus
- audio out... Headphone level would be best
- 3v3 power and logic level
- I want to talk to the MIDI player using a digital pin from a 3v3 Teensy board.

Is this a better question for Sales?

Davidelvig
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Re: Minimal MIDI decoder

Post by Davidelvig » Fri 2015-11-13 18:35

... and I plan to use Eagle for board layout.
Would there be sample Eagle files for the 1033 (or other chosen chip)?

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pasi
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Re: Minimal MIDI decoder

Post by pasi » Wed 2015-11-18 17:08

All out chips provide headphone output and can use upto 3v6 IO and analog voltages. You may need regulators for core voltage (CVDD).

Would the MIDI be real-time MIDI stream or from a file? From where would the WAV to be mixed come from?

What would the communication with the controller contain? Commands to play, status information ?

The alternatives for new designed would be vs1103b and vs1053b / vs8053b. Both support real-time midi mode from UART (31250bps). They can also decode MIDI file data when it is sent as a stream to the serial data interface. VS1103b can also decode two streams at the same time (MIDI and WAV files) if the controller handles the sending of data. vs1053/vs8053 can run with higher clock and may thus have higher-quality MIDI generation (more notes, can have reverb, and EarSpeaker processing on at the same time).
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Davidelvig
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Re: Minimal MIDI decoder

Post by Davidelvig » Wed 2015-12-23 7:33

Sorry for my delay
MIDI in would be a realtime stream from a wind controller.
WAV would be from a disk file.
I could have an analog audio stream as well, or as an option.
MIDI data would be mostly notes, and expression, with instrument change, vibrato, pitch bend or tune, glissando and other expressive effects.

The MIDI would be monophonic mostly, perhaps with the option to play a duet or trio with yourself.

Does that help focus the search?

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Re: Minimal MIDI decoder

Post by Davidelvig » Sun 2017-03-05 22:00

I'm restarting this thread...
I've started working with Eagle, and I'd like to build a board that takes MIDI input and delivers analog audio to headphones.
A really simple use of the VS1053, I hope.

I have downloaded and schedule out a 1053 board using eagle with the lbr files from VLSI.
I'm connecting to a 3V3 Teensy micro controller.

My questions:
1) Do I need to put a crystal, on the board, or does the 1053 have an on-board crystal?
2) Which power input(s) need connecting to 3V3?
3) Other than GPIO 0 (HIGH) and GPIO 1 (LOW) and RX and the 3 earbud connections and all grounds, what need I connect?
4) Is there a minimalist set of Eagle files to start with that I could download?

Thanks
Dave

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pasi
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Re: Minimal MIDI decoder

Post by pasi » Mon 2017-03-06 12:15

1) Yes, you need the crystal. (Or a logic-level clock of close to 12.288MHz.)
2) IOVDD and AVDD can use 3.3V, CVDD requires 1.8V .
3) It would be good if you have enough GPIO to connect the Serial Control Interface (SCI) pins (xCS, SCLK, SI, SO, pull-up on xDCS).

Connect xTEST to IOVDD. Have capacitor to gnd and pull-up on xRESET (or control from the controller).

You need the regular analog output components and capacitor on RCAP.

Also make sure that data is not sent to RX before the vs1053b is ready in the real-time MIDI mode.

For design files, try the packages in http://www.vlsi.fi/en/support/evaluatio ... board.html
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Davidelvig
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Re: Minimal MIDI decoder

Post by Davidelvig » Tue 2017-03-07 1:28

Thanks.
Should the 1.4 schematic be fine for me, or need I look at the 2.x schematic for my simpler purposes?
(1.4 has fewer components and connections)

And, should I have been able to construct your list of to-do's from the spec sheet, or is there another recipe-style document I could download and study?

My near-term goal is an Eagle design that I can send to get manufactured.

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