Merge pull request #19 from midilab/esp32-support

Experimental Esp32 support

examples/ESP32UartMasterMidiClock/ESP32UartMasterMidiClock.ino

@@ -0,0 +1,84 @@
+/* Uart MIDI Sync Box
+ *  
+ * This example demonstrates how to change the Uart MIDI 
+ * device name on ESP32 family. 
+ * 
+ * This example code is in the public domain.
+ * 
+ * ...
+ * 
+ */
+#include <uClock.h>
+
+// MIDI clock, start and stop byte definitions - based on MIDI 1.0 Standards.
+#define MIDI_CLOCK 0xF8
+#define MIDI_START 0xFA
+#define MIDI_STOP  0xFC
+
+// the blue led
+#define LED_BUILTIN    2
+
+volatile bool _midi_clk_income = false;
+
+uint8_t bpm_blink_timer = 1;
+void handle_bpm_led(uint32_t tick)
+{
+  // BPM led indicator
+  if ( !(tick % (96)) || (tick == 1) ) {  // first compass step will flash longer
+    bpm_blink_timer = 8;
+    digitalWrite(LED_BUILTIN, HIGH);
+  } else if ( !(tick % (24)) ) {   // each quarter led on
+    bpm_blink_timer = 1;
+    digitalWrite(LED_BUILTIN, HIGH);
+  } else if ( !(tick % bpm_blink_timer) ) { // get led off
+    digitalWrite(LED_BUILTIN, LOW);
+  }
+}
+
+// Internal clock handlers
+void ClockOut96PPQN(uint32_t tick) {
+  // Send MIDI_CLOCK to external gears
+  //Serial.write(MIDI_CLOCK);
+  _midi_clk_income = true;
+  handle_bpm_led(tick);
+}
+
+void onClockStart() {
+  Serial.write(MIDI_START);
+}
+
+void onClockStop() {
+  Serial.write(MIDI_STOP);
+}
+
+void setup() {
+  // Initialize serial communication at 31250 bits per second, the default MIDI serial speed communication:
+  Serial.begin(31250);
+
+  // A led to count bpms
+  pinMode(LED_BUILTIN, OUTPUT);
+  
+  // Setup our clock system
+  // Inits the clock
+  uClock.init();
+  // Set the callback function for the clock output to send MIDI Sync message.
+  uClock.setClock96PPQNOutput(ClockOut96PPQN);
+  // Set the callback function for MIDI Start and Stop messages.
+  uClock.setOnClockStartOutput(onClockStart);  
+  uClock.setOnClockStopOutput(onClockStop);
+  // Set the clock BPM to 126 BPM
+  uClock.setTempo(126);
+  // Starts the clock, tick-tac-tick-tac...
+  uClock.start();
+}
+
+// Do it whatever to interface with Clock.stop(), Clock.start(), Clock.setTempo() and integrate your environment...
+void loop() {
+  // watch for income signal from uClock to fire the clock over midi
+  if (_midi_clk_income) {
+    Serial.write(MIDI_CLOCK);
+    noInterrupts();
+    _midi_clk_income = false;
+    interrupts();
+  }
+}

library.properties

@@ -1,10 +1,10 @@
 name=uClock
-version=1.1.4
+version=1.2.0
 author=Romulo Silva <contact@midilab.co>
 maintainer=Romulo Silva <contact@midilab.co>
 sentence=BPM clock generator for Arduino platform.
-paragraph=A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(Teensy and Seedstudio XIAO M0)
+paragraph=A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(Teensy, Seedstudio XIAO M0 and ESP32)
 category=Timing
 url=https://github.com/midilab/uClock
-architectures=avr,arm,samd
+architectures=avr,arm,samd,esp32
 includes=uClock.h

src/uClock.cpp

@@ -1,8 +1,8 @@
 /*!
  *  @file       uClock.cpp
  *  Project     BPM clock generator for Arduino
- *  @brief      A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(Teensy and Seedstudio XIAO M0)
- *  @version    1.1.4
+ *  @brief      A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(Teensy, Seedstudio XIAO M0 and ESP32)
+ *  @version    1.2.0
  *  @author     Romulo Silva
  *  @date       10/06/2017
  *  @license    MIT - (c) 2022 - Romulo Silva - contact@midilab.co
@@ -27,15 +27,16 @@
  */
 #include "uClock.h"
 
-// 
 // Timer setup for work clock
 //
-// all non-avr timmers setup
 // Teensyduino port
+//
 #if defined(TEENSYDUINO)
 	IntervalTimer _uclockTimer;
 #endif
+//
 // Seedstudio XIAO M0 port
+//
 #if defined(SEEED_XIAO_M0)
 	// 24 bits timer
 	#include <TimerTCC0.h>
@@ -44,6 +45,13 @@ IntervalTimer _uclockTimer;
 	//#include <TimerTC3.h>
 	// uses TimerTc3
 #endif
+//
+// ESP32 family
+//
+#if defined(ARDUINO_ARCH_ESP32) || defined(ESP32)
+	hw_timer_t * _uclockTimer = NULL;
+	#define TIMER_ID	0
+#endif
 
 #if defined(ARDUINO_ARCH_AVR)
 void uclockInitTimer()
@@ -87,6 +95,19 @@ void uclockInitTimer()
 		// attach to generic uclock ISR
 		TimerTcc0.attachInterrupt(uclockISR);
 	#endif
+
+	#if defined(ARDUINO_ARCH_ESP32) || defined(ESP32)
+		_uclockTimer = timerBegin(TIMER_ID, 80, true);
+
+		// attach to generic uclock ISR
+		timerAttachInterrupt(_uclockTimer, &uclockISR, true);
+
+		// init clock tick time
+		timerAlarmWrite(_uclockTimer, init_clock, true); 
+
+		// activate it!
+		timerAlarmEnable(_uclockTimer);
+	#endif
 }
 #endif
 
@@ -213,6 +234,10 @@ void uClockClass::setTimerTempo(float bpm)
 	#if defined(SEEED_XIAO_M0)
 		TimerTcc0.setPeriod(tick_us_interval);
 	#endif
+
+	#if defined(ARDUINO_ARCH_ESP32) || defined(ESP32)
+		timerAlarmWrite(_uclockTimer, tick_us_interval, true); 
+	#endif
 #endif
 }
 

src/uClock.h

@@ -1,8 +1,8 @@
 /*!
  *  @file       uClock.h
  *  Project     BPM clock generator for Arduino
- *  @brief      A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(Teensy and Seedstudio XIAO M0)
- *  @version    1.1.4
+ *  @brief      A Library to implement BPM clock tick calls using hardware interruption. Supported and tested on AVR boards(ATmega168/328, ATmega16u4/32u4 and ATmega2560) and ARM boards(Teensy, Seedstudio XIAO M0 and ESP32)
+ *  @version    1.2.0
  *  @author     Romulo Silva
  *  @date       10/06/2017
  *  @license    MIT - (c) 2022 - Romulo Silva - contact@midilab.co
@@ -44,6 +44,7 @@ namespace umodular { namespace clock {
 #define MAX_BPM	300
 
 // want a different avr clock support?
+// TODO: we should do this using macro guards for avrs different clocks
 #define AVR_CLOCK_FREQ	16000000
 
 #define PHASE_FACTOR 16