Incoming Clock to BPM

[ghost]

how do i read an incoming midi clock and turn it to a BPM I can display?

[mink99]

Midi clock is basically 1/96 th notes.
So you need to measure one minute as exactly as possible, count the ticks, and do the maths.
one bpm is a quarter note per minute.
Do not expect this to be exact, even tools like the beat step pro fail on this exercise…..

[franky47]

To catch the MIDI Clock messages, the simplest way is to use its associated callback:

void onClock()
{
  // Time maths goes here
}

void setup()
{
  MIDI.begin();
  MIDI.setHandleClock(onClock);
}

void loop()
{
  MIDI.read();
}

[ghost]

this prints bpm to serial monitor
thanks for the suggestions, solved.
`#include <MIDI.h>

byte midi_clock = 0xf8;
unsigned long int startTime;
int beatCount;
bool counting = false;
long int bpm;
long int noteTime;

MIDI_CREATE_INSTANCE(HardwareSerial, Serial1, MIDI);

void setup() {
MIDI.begin(MIDI_CHANNEL_OMNI);
Serial.begin(57600);
Serial.println("MIDI Input Test");
}

void loop() {

if (MIDI.read()) { // Is there a MIDI message incoming ?
byte type = MIDI.getType();
if (type == midi_clock) {
if ( not counting) { // first time you have seen a clock message in this batch
startTime = millis();
counting = true;
beatCount = 1;
}
else {
beatCount += 1;
if (beatCount >= 96) {
noteTime = millis() - startTime;
counting = false;
// you now have the time for one note so calculate the BPM
bpm = 240000/noteTime;
// now display the BPM
Serial.println(bpm);
}
}
}
}
}`

[franky47]

Note: I found the repo where I copy-pasted the running average from, it's my project to sync a Line6 DL4 to a MIDI clock. If you want to learn more about C++ and templates, you can have a peek:

https://github.com/franky47/dl4-midi-sync

[m-r-m-s]

Oh this is a great project! I have a DL4 so I may give this a try at some point! And very helpful as a learning guide too.

[franky47]

There's a bit of soldering to do to connect things together, I'll try and dig out a blog post draft I started writing about it.

[franky47]

Here's the blog post, which explains how the whole thing came together:
https://github.com/franky47/dl4-midi-sync/blob/main/blog-post.md

[m-r-m-s]

Here's the blog post, which explains how the whole thing came together: https://github.com/franky47/dl4-midi-sync/blob/main/blog-post.md

Fantastic - thanks again 🙌!

[mink99]

Please keep in mind that Serial.println is incredibly slow. Even if you are on a mega and use Serial1 for midi , if you are measuring permanently, the println will tamper the measuring. We are not on a multiprocessor machine here.

[mink99]

Additionally there is always jitter on any device distributing midi clock. If there is a PC using a cheap usb midi interface, it is rather unreliable to put out any measuring. (And just forget about blutooth midi)