Arduino MIDI Clock

[ixtern]

This is my first prototype Eurorack module - MIDI Clock. Heart of it's construction is the Arduino Nano module. Code was mainly based on Dieter Van de Walle "arduino-midi-clock".
Specification:
- BPM range: 40-300,
- BPM blinking LED indication,
- 2 MIDI Clock Outputs,
- BPM Sync short pulse output,
- BPM Sync long pulse output,
- Internal MIDI Clock and BPM Sync connector,
- Start/Stop button,
- Continue/Stop button,
- 0.96" OLED display,
- Encoder for BPM setting,
- Encoder's switch for encoder step toggle (x1 or x10).

Components were soldered on the common prototype PCB using teflon-coated 28-30AWG wires for connections.
Notice: Hardware debouncer (MC14490) was used just for fun and to test it, in your construction you can
connect buttons directly to the Aduino Nano inputes and use software debouncer.
If you wonder why there are free MC14490 inputs left instead to be used for encoder pins then the reason
is different debounce time needed for button and for encoders.
C101 (47nF) connected to the pins 7 and 9 of the MC14490 sets debounce time appropriate for buttons.
Recommended capacity for encoders is 1.5nF (5 ms delay). Nevermind, it's just a curiosity, you don't need it.

Module is supplied by standard Eurorack 16-pin (2x8) connector, so it is possible to have not only +5V outputs
but also +12V (or +15V, depends on your power supply). An additional transistor and resistor is needed for such output
(like the blinking LED circuit).

For testing purposes module may be supplied from standard microUSB +5V through Arduino Nano USB connector.

Front panel file in Front Panel Designer is included.

Kicad files with project/schematic are also included (no PCB project as I didn't needed it).
sym-lib-table file should be edited in text editor to point correct path to the MC14490 library.
MC14490 library files should be placed in the Kicad lib folder (or where you want if all paths in Kicad are correctly set).
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MidiClock_sch.jpg
Description:	Arduino MIDI Clock schematic file
Filesize:	368.85 KB
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MidiClockPulses.png
Description:	MIDI Clock output signals
Filesize:	13.94 KB
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MIDI_CLOCK_sch.pdf
Description:	Arduino MIDI Clock schematic PDF file	Download (listen)
Filename:	MIDI_CLOCK_sch.pdf
Filesize:	107.28 KB
Downloaded:	507 Time(s)

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ArduinoMIDIClock.ino
Description:	Arduino sketch for MIDI Clock	Download (listen)
Filename:	ArduinoMIDIClock.ino
Filesize:	14.37 KB
Downloaded:	585 Time(s)

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IXT-MIDI_CLOCK.fpd
Description:	MIDI Clock panel (Front Panel Designer file)	Download (listen)
Filename:	IXT-MIDI_CLOCK.fpd
Filesize:	1.41 KB
Downloaded:	418 Time(s)

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[ixtern]

Additional files for Arduino MIDI Clock.

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20181027_120541.jpg
Description:	Clock "main board"
Filesize:	1.71 MB
Viewed:	391 Time(s)
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20181027_121358.jpg
Description:	Crude panel
Filesize:	1.93 MB
Viewed:	462 Time(s)
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20181027_120721.jpg
Description:	Wiring of panel
Filesize:	2.38 MB
Viewed:	380 Time(s)
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20181027_121100.jpg
Description:	OLED display mounting
Filesize:	1.31 MB
Viewed:	369 Time(s)
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IXT-MIDI_CLOCK_with_refs.pdf
Description:	MIDI Clock panel with reference points	Download (listen)
Filename:	IXT-MIDI_CLOCK_with_refs.pdf
Filesize:	6.58 KB
Downloaded:	395 Time(s)

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[ixtern]

Kicad files for Arduino MIDI Clock.

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Kicad_MidiClock.zip
Description:	Kicad files for Arduino MIDI Clock	Download (listen)
Filename:	Kicad_MidiClock.zip
Filesize:	15.43 KB
Downloaded:	435 Time(s)

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[ixtern]

As you can see on the photos, IC used in MIDI Clock is a 74HC4050, not 4050 as can be seen on a Kicad schematic. Simply Kicad haven't proper name in library and later I have forgotten to rename IC from 4050 to 74HC4050.