added clock decimal precision(128.5bpm). added a buffer for average interval tick reading on getTempo() to smooth slave tempo retrive. Revised Teensy USB midi clock monitor

pull/7/head 0.9.4
midilab 4 years ago
parent 2f70ed8b82
commit c71e55615c
  1. 41
      examples/TeensyUsbSlaveMidiClockMonitor/TeensyUsbSlaveMidiClockMonitor.ino
  2. 2
      library.properties
  3. 38
      src/uClock.cpp
  4. 19
      src/uClock.h

@ -4,12 +4,18 @@
* MIDI hid compilant slave clock box with * MIDI hid compilant slave clock box with
* monitor support using oled displays * monitor support using oled displays
* *
* Making use of a 250 usceconds timer to * Making use of a 16 usceconds timer to
* handle MIDI input to avoid jitter on clock * handle MIDI input to avoid jitter on clock
* *
* You need the following libraries to make it work * You need the following libraries to make it work
* - u8g2 * - u8g2
* - uClock * - uClock
*
* This example make use of drift values (1, 4)
* respectively for internal and external drift reference.
* This example was tested on a macbook
* running ableton live 9 as master clock
*
* This example code is in the public domain. * This example code is in the public domain.
*/ */
@ -28,8 +34,8 @@ IntervalTimer teensyTimer;
#define MIDI_START 0xFA #define MIDI_START 0xFA
#define MIDI_STOP 0xFC #define MIDI_STOP 0xFC
char bpm_str[3]; char bpm_str[4];
uint16_t bpm = 126; float bpm = 126;
uint8_t bpm_blink_timer = 1; uint8_t bpm_blink_timer = 1;
uint8_t clock_state = 1; uint8_t clock_state = 1;
@ -60,6 +66,7 @@ void onClockStart() {
void onClockStop() { void onClockStop() {
usbMIDI.sendRealTime(MIDI_STOP); usbMIDI.sendRealTime(MIDI_STOP);
digitalWrite(LED_BUILTIN, LOW);
} }
// External clock handlers // External clock handlers
@ -105,15 +112,16 @@ void setup() {
// //
// Setup our clock system // Setup our clock system
// drift for USB Teensy // drift for USB Teensy
uClock.setDrift(1); uClock.setDrift(1, 4);
uClock.init(); uClock.init();
uClock.setClock96PPQNOutput(ClockOut96PPQN); uClock.setClock96PPQNOutput(ClockOut96PPQN);
// For MIDI Sync Start and Stop // For MIDI Sync Start and Stop
uClock.setOnClockStartOutput(onClockStart); uClock.setOnClockStartOutput(onClockStart);
uClock.setOnClockStopOutput(onClockStop); uClock.setOnClockStopOutput(onClockStop);
uClock.setMode(uClock.EXTERNAL_CLOCK); uClock.setMode(uClock.EXTERNAL_CLOCK);
// make use of 250us timer to handle midi input sync // make use of 16us timer to handle midi input sync
teensyTimer.begin(handleMidiInput, 250); teensyTimer.begin(handleMidiInput, 16);
teensyTimer.priority(80);
} }
void handleMidiInput() { void handleMidiInput() {
@ -121,12 +129,27 @@ void handleMidiInput() {
} }
} }
void printBpm(float _bpm, uint8_t col, uint8_t line) {
int b = (int)_bpm;
int c = (int)((_bpm-b)*10);
itoa(b, bpm_str, 10);
if (b > 99) {
u8x8->drawUTF8(col, line, bpm_str);
} else {
bpm_str[2] = "\0";
u8x8->drawUTF8(col, line, " ");
u8x8->drawUTF8(col+1, line, bpm_str);
}
u8x8->drawUTF8(col+3, line, ".");
itoa(c, bpm_str, 10);
u8x8->drawUTF8(col+4, line, bpm_str);
u8x8->drawUTF8(col+5, line, "bpm");
}
void loop() { void loop() {
if (bpm != uClock.getTempo()) { if (bpm != uClock.getTempo()) {
bpm = uClock.getTempo(); bpm = uClock.getTempo();
itoa(bpm, bpm_str, 10); printBpm(bpm, 8, 7);
u8x8->drawUTF8(10, 7, bpm_str);
u8x8->drawUTF8(13, 7, "bpm");
} }
if (clock_state != uClock.state) { if (clock_state != uClock.state) {
clock_state = uClock.state; clock_state = uClock.state;

@ -1,5 +1,5 @@
name=uClock name=uClock
version=0.9.2 version=0.9.4
author=Romulo Silva <contact@midilab.co>, Manuel Odendahl <wesen@ruinwesen.com> author=Romulo Silva <contact@midilab.co>, Manuel Odendahl <wesen@ruinwesen.com>
maintainer=Romulo Silva <contact@midilab.co> maintainer=Romulo Silva <contact@midilab.co>
sentence=BPM clock generator for Arduino and Teensy boards sentence=BPM clock generator for Arduino and Teensy boards

@ -3,7 +3,7 @@
* Project BPM clock generator for Arduino * Project BPM clock generator for Arduino
* @brief A Library to implement BPM clock tick calls using hardware timer1 interruption. Tested on ATmega168/328, ATmega16u4/32u4 and ATmega2560. * @brief A Library to implement BPM clock tick calls using hardware timer1 interruption. Tested on ATmega168/328, ATmega16u4/32u4 and ATmega2560.
* Derived work from mididuino MidiClock class. (c) 2008 - 2011 - Manuel Odendahl - wesen@ruinwesen.com * Derived work from mididuino MidiClock class. (c) 2008 - 2011 - Manuel Odendahl - wesen@ruinwesen.com
* @version 0.9.3 * @version 0.9.4
* @author Romulo Silva * @author Romulo Silva
* @date 08/21/2020 * @date 08/21/2020
* @license MIT - (c) 2020 - Romulo Silva - contact@midilab.co * @license MIT - (c) 2020 - Romulo Silva - contact@midilab.co
@ -39,13 +39,14 @@ IntervalTimer _teensyTimer;
void teensyInterrupt(); void teensyInterrupt();
void initTeensyTimer() void initTeensyTimer()
{ {
// 62500Hz
_teensyTimer.begin(teensyInterrupt, 16); _teensyTimer.begin(teensyInterrupt, 16);
// Set the interrupt priority level, controlling which other interrupts // Set the interrupt priority level, controlling which other interrupts
// this timer is allowed to interrupt. Lower numbers are higher priority, // this timer is allowed to interrupt. Lower numbers are higher priority,
// with 0 the highest and 255 the lowest. Most other interrupts default to 128. // with 0 the highest and 255 the lowest. Most other interrupts default to 128.
// As a general guideline, interrupt routines that run longer should be given // As a general guideline, interrupt routines that run longer should be given
// lower priority (higher numerical values). // lower priority (higher numerical values).
//_teensyTimer.priority(128); _teensyTimer.priority(0);
} }
#else #else
void initArduinoTimer() void initArduinoTimer()
@ -103,6 +104,7 @@ uClockClass::uClockClass()
// 1 is good on teensy lc usb midi // 1 is good on teensy lc usb midi
internal_drift = 11; internal_drift = 11;
external_drift = 11; external_drift = 11;
tempo = 120;
pll_x = 220; pll_x = 220;
start_timer = 0; start_timer = 0;
last_interval = 0; last_interval = 0;
@ -116,11 +118,13 @@ uClockClass::uClockClass()
onClock16PPQNCallback = NULL; onClock16PPQNCallback = NULL;
onClockStartCallback = NULL; onClockStartCallback = NULL;
onClockStopCallback = NULL; onClockStopCallback = NULL;
// first interval calculus
setTempo(tempo);
} }
void uClockClass::init() void uClockClass::init()
{ {
setTempo(120);
initWorkTimer(); initWorkTimer();
} }
@ -161,7 +165,7 @@ void uClockClass::pause()
} }
} }
void uClockClass::setTempo(uint16_t bpm) void uClockClass::setTempo(float bpm)
{ {
if (mode == EXTERNAL_CLOCK) { if (mode == EXTERNAL_CLOCK) {
return; return;
@ -178,19 +182,26 @@ void uClockClass::setTempo(uint16_t bpm)
tempo = bpm; tempo = bpm;
ATOMIC( ATOMIC(
interval = (uint16_t)((156250.0 / tempo) - internal_drift);
//interval = 62500 / (tempo * 24 / 60) - internal_drift; //interval = 62500 / (tempo * 24 / 60) - internal_drift;
interval = (uint16_t)(156250 / tempo) - internal_drift;
) )
} }
uint16_t uClockClass::getTempo() float uClockClass::getTempo()
{ {
if (mode == EXTERNAL_CLOCK) { if (mode == EXTERNAL_CLOCK) {
uint16_t external_interval; uint32_t acc = 0;
ATOMIC( uint8_t acc_counter = 0;
external_interval = interval; for (uint8_t i=0; i < EXT_INTERVAL_BUFFER_SIZE; i++) {
) if ( ext_interval_buffer[i] != 0) {
tempo = (156250 / (external_interval + external_drift)); acc += ext_interval_buffer[i];
++acc_counter;
}
}
if (acc != 0) {
// get average interval, because MIDI sync world is a wild place...
tempo = (float)(156250.0 / ((acc / acc_counter) + external_drift));
}
} }
return tempo; return tempo;
} }
@ -232,6 +243,8 @@ void uClockClass::resetCounters()
mod6_counter = 0; mod6_counter = 0;
indiv96th_counter = 0; indiv96th_counter = 0;
inmod6_counter = 0; inmod6_counter = 0;
ext_interval_buffer[EXT_INTERVAL_BUFFER_SIZE] = {0};
ext_interval_idx = 0;
} }
// TODO: Tap stuff // TODO: Tap stuff
@ -273,6 +286,9 @@ void uClockClass::handleExternalClock()
} else { } else {
interval = (((uint32_t)interval * (uint32_t)pll_x) + (uint32_t)(256 - pll_x) * (uint32_t)last_interval) >> 8; interval = (((uint32_t)interval * (uint32_t)pll_x) + (uint32_t)(256 - pll_x) * (uint32_t)last_interval) >> 8;
} }
// accumulate interval incomming ticks data(for a better getTempo stability over bad clocks)
ext_interval_buffer[ext_interval_idx] = interval;
ext_interval_idx = ++ext_interval_idx % EXT_INTERVAL_BUFFER_SIZE;
break; break;
} }
} }

@ -3,7 +3,7 @@
* Project BPM clock generator for Arduino * Project BPM clock generator for Arduino
* @brief A Library to implement BPM clock tick calls using hardware timer1 interruption. Tested on ATmega168/328, ATmega16u4/32u4 and ATmega2560. * @brief A Library to implement BPM clock tick calls using hardware timer1 interruption. Tested on ATmega168/328, ATmega16u4/32u4 and ATmega2560.
* Derived work from mididuino MidiClock class. (c) 2008 - 2011 - Manuel Odendahl - wesen@ruinwesen.com * Derived work from mididuino MidiClock class. (c) 2008 - 2011 - Manuel Odendahl - wesen@ruinwesen.com
* @version 0.9.3 * @version 0.9.4
* @author Romulo Silva * @author Romulo Silva
* @date 08/21/2020 * @date 08/21/2020
* @license MIT - (c) 2020 - Romulo Silva - contact@midilab.co * @license MIT - (c) 2020 - Romulo Silva - contact@midilab.co
@ -35,6 +35,8 @@
#define PHASE_FACTOR 16 #define PHASE_FACTOR 16
#define EXT_INTERVAL_BUFFER_SIZE 40
#define SECS_PER_MIN (60UL) #define SECS_PER_MIN (60UL)
#define SECS_PER_HOUR (3600UL) #define SECS_PER_HOUR (3600UL)
#define SECS_PER_DAY (SECS_PER_HOUR * 24L) #define SECS_PER_DAY (SECS_PER_HOUR * 24L)
@ -47,11 +49,6 @@ enum {
STARTED STARTED
} state; } state;
enum {
INTERNAL_CLOCK = 0,
EXTERNAL_CLOCK
} mode;
class uClockClass { class uClockClass {
private: private:
@ -67,7 +64,6 @@ class uClockClass {
volatile uint16_t interval; volatile uint16_t interval;
volatile uint16_t last_clock; volatile uint16_t last_clock;
uint8_t ppqn;
uint32_t div96th_counter; uint32_t div96th_counter;
uint32_t div32th_counter; uint32_t div32th_counter;
uint32_t div16th_counter; uint32_t div16th_counter;
@ -77,13 +73,16 @@ class uClockClass {
uint16_t pll_x; uint16_t pll_x;
uint8_t internal_drift; uint8_t internal_drift;
uint8_t external_drift; uint8_t external_drift;
uint16_t tempo; float tempo;
uint32_t start_timer; uint32_t start_timer;
uint8_t mode; uint8_t mode;
uint16_t last_interval; uint16_t last_interval;
uint16_t sync_interval; uint16_t sync_interval;
uint16_t ext_interval_buffer[EXT_INTERVAL_BUFFER_SIZE];
uint16_t ext_interval_idx;
public: public:
uint8_t INTERNAL_CLOCK = 0; uint8_t INTERNAL_CLOCK = 0;
@ -122,8 +121,8 @@ class uClockClass {
void start(); void start();
void stop(); void stop();
void pause(); void pause();
void setTempo(uint16_t bpm); void setTempo(float bpm);
uint16_t getTempo(); float getTempo();
void setDrift(uint8_t internal, uint8_t external = 255); void setDrift(uint8_t internal, uint8_t external = 255);
// external timming control // external timming control

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