glasslathe: fix frequency for zero

2 files changed, 99 insertions, 92 deletions

diff --git a/linz/glasslathe/platformio.ini b/linz/glasslathe/platformio.ini
index f2cb76e..ed9ba0a 100644
--- a/linz/glasslathe/platformio.ini
+++ b/linz/glasslathe/platformio.ini
@@ -8,8 +8,7 @@
 ; Please visit documentation for the other options and examples
 ; https://docs.platformio.org/page/projectconf.html
 
-[env:nanoatmega328new]
-platform = atmelavr
-board = nanoatmega328new
+[env:mkrzero]
+platform = atmelsam
 framework = arduino
-lib_deps = paulstoffregen/TimerOne @ ^1.1
\ No newline at end of file
+board = mkrzero
diff --git a/linz/glasslathe/src/main.cpp b/linz/glasslathe/src/main.cpp
index 85b49dd..cd39208 100644
--- a/linz/glasslathe/src/main.cpp
+++ b/linz/glasslathe/src/main.cpp
@@ -1,104 +1,112 @@
 #include <Arduino.h>
-#include <TimerOne.h>
 
-void analogWriteSAH_Init(void)
+#define LED_PIN 4
+#define POT_PIN 2
+
+#define POT_JITTER_THRESHOLD 10
+
+int potValue = 0;
+
+void SetupTimer()
 {
-  // Stop the timer while we muck with it
-  TCCR1B = (0 << ICNC1) | (0 << ICES1) | (0 << WGM13) | (0 << WGM12) | (0 << CS12) | (0 << CS11) | (0 << CS10);
-
-  // Set the timer to mode 14...
-  //
-  // Mode  WGM13  WGM12  WGM11  WGM10  Timer/Counter Mode of Operation  TOP   Update of OCR1x at TOV1  Flag Set on
-  //              CTC1   PWM11  PWM10
-  // ----  -----  -----  -----  -----  -------------------------------  ----  -----------------------  -----------
-  // 14    1      1      1      0      Fast PWM                         ICR1  BOTTOM                   TOP
-
-  // Set output on Channel A to...
-  //
-  // COM1A1  COM1A0  Description
-  // ------  ------  -----------------------------------------------------------
-  // 1       0       Clear OC1A/OC1B on Compare Match (Set output to low level).
-  TCCR1A =
-      (1 << COM1A1) | (0 << COM1A0) |   // COM1A1, COM1A0 = 1, 0
-      (0 << COM1B1) | (0 << COM1B0) |
-      (1 << WGM11)  | (0 << WGM10);     // WGM11, WGM10 = 1, 0
-
-  // Set TOP to...
-  //
-  // fclk_I/O = 16000000
-  // N        = 1
-  // TOP      = 799
-  //
-  // fOCnxPWM = fclk_I/O / (N * (1 + TOP))
-  // fOCnxPWM = 16000000 / (1 * (1 + 799))
-  // fOCnxPWM = 16000000 / 800
-  // fOCnxPWM = 20000
-  ICR1 = 799;
-
-  // Ensure the first slope is complete
-  TCNT1 = 0;
-
-  // Ensure Channel B is irrelevant
-  OCR1B = 0;
-
-  // Ensure Channel A starts at zero / off
-  OCR1A = 0;
-
-  // We don't need no stinkin interrupts
-  TIMSK1 = (0 << ICIE1) | (0 << OCIE1B) | (0 << OCIE1A) | (0 << TOIE1);
-
-  // Ensure the Channel A pin is configured for output
-  DDRB |= (1 << DDB1);
-
-  // Start the timer...
-  //
-  // CS12  CS11  CS10  Description
-  // ----  ----  ----  ------------------------
-  // 0     0     1     clkI/O/1 (No prescaling)
-  TCCR1B =
-      (0 << ICNC1) | (0 << ICES1) |
-      (1 << WGM13) | (1 << WGM12) |              // WGM13, WGM12 = 1, 1
-      (0 << CS12) | (0 << CS11) | (1 << CS10);
+  GCLK->GENDIV.reg = GCLK_GENDIV_DIV(1) |          // Divide the 48MHz clock source by divisor 1: 48MHz/1=48MHz
+                     GCLK_GENDIV_ID(4);            // Select Generic Clock (GCLK) 4
+  while (GCLK->STATUS.bit.SYNCBUSY);               // Wait for synchronization
+
+  GCLK->GENCTRL.reg = GCLK_GENCTRL_IDC |           // Set the duty cycle to 50/50 HIGH/LOW
+                      GCLK_GENCTRL_GENEN |         // Enable GCLK4
+                      GCLK_GENCTRL_SRC_DFLL48M |   // Set the 48MHz clock source
+                      GCLK_GENCTRL_ID(4);          // Select GCLK4
+  while (GCLK->STATUS.bit.SYNCBUSY);               // Wait for synchronization
+
+  // Enable the port multiplexer for port D5
+  PORT->Group[g_APinDescription[5].ulPort].PINCFG[g_APinDescription[5].ulPin].bit.PMUXEN = 1;
+
+  // Connect the TCC timers to the port outputs - port pins are paired odd PMUO and even PMUXE
+  // F & E specify the timers: TCC0, TCC1 and TCC2
+  PORT->Group[g_APinDescription[5].ulPort].PMUX[g_APinDescription[5].ulPin >> 1].reg = PORT_PMUX_PMUXO_F;
+ 
+  // Feed GCLK4 to TCC0 and TCC1
+  GCLK->CLKCTRL.reg = GCLK_CLKCTRL_CLKEN |         // Enable GCLK4 to TCC0 and TCC1
+                      GCLK_CLKCTRL_GEN_GCLK4 |     // Select GCLK4
+                      GCLK_CLKCTRL_ID_TCC0_TCC1;   // Feed GCLK4 to TCC0 and TCC1
+  while (GCLK->STATUS.bit.SYNCBUSY);                // Wait for synchronization 
+
+  TCC0->WAVE.reg = TCC_WAVE_WAVEGEN_NPWM;          // Single slope PWM operation         
+  while (TCC0->SYNCBUSY.bit.WAVE);                 // Wait for synchronization
+ 
+  TCC0->PER.reg = 4799;                            // Set the frequency of the PWM on TCC0 to 10kHz
+  while (TCC0->SYNCBUSY.bit.PER);                  // Wait for synchronization
+
+  TCC0->CC[2].reg = 2399;                          // TCC0 CC2 - 50% duty-cycle on D10
+  while (TCC0->SYNCBUSY.bit.CC2);                  // Wait for synchronization
+  TCC0->CC[3].reg = 2399;                          // TCC0 CC3 - 50% duty-cycle on D12
+  while (TCC0->SYNCBUSY.bit.CC3);                  // Wait for synchronization
+ 
+  // Divide the 48MHz signal by 1 giving 48MHz (20.83ns) TCC0 timer tick and enable the timer
+  TCC0->CTRLA.reg |= TCC_CTRLA_PRESCALER_DIV1 |    // Divide GCLK4 by 1
+                     TCC_CTRLA_ENABLE;             // Enable the TCC0 output
+  while (TCC0->SYNCBUSY.bit.ENABLE);               // Wait for synchronization
+
+  //Stop TCC0 counter on MCU initialization (stepper initially stopped)
+  //TCC0->CTRLBSET.reg = TCC_CTRLBSET_CMD_STOP;    // Force the TCC0 timer to STOP
+  //while (TCC0->SYNCBUSY.bit.CTRLB);              // Wait for synchronization
 }
 
-void analogWriteD9(uint16_t value)
+void StopTimer()
 {
-  if ((value >= 0) && (value < 800))
-  {
-    OCR1A = value;
-  }
+  //Stop TCC0 counter on MCU initialization (stepper initially stopped)
+  TCC0->CTRLBSET.reg = TCC_CTRLBSET_CMD_STOP;           // Force the TCC0 timer to STOP
+  while (TCC0->SYNCBUSY.bit.CTRLB);                     // Wait for synchronization
+}
+
+void RestartTimer()
+{
+  // put your main code here, to run repeatedly:
+  TCC0->CTRLBSET.reg = TCC_CTRLBSET_CMD_RETRIGGER;      // Force the TCC0 timer to START
+  while (TCC0->SYNCBUSY.bit.CTRLB);                     // Wait for synchronization
+}
+
+uint32_t stepperFrequencyDivisor = 4799;             //Sets the starting frequency equal to 1hz
+
+void SetFrequencyOutput(uint16_t frequency)
+{
+  stepperFrequencyDivisor = round(48000000 / frequency);
+  
+  TCC0->PERB.reg = stepperFrequencyDivisor - 1;         // Set the starting frequency of the PWM on TCC0 to 1Hz
+  while (TCC0->SYNCBUSY.bit.PERB);                      // Wait for synchronization
+  
+  TCC0->CCB[1].reg = (stepperFrequencyDivisor / 2) - 1; // TCC0 CC2 - 50% duty-cycle
+  while (TCC0->SYNCBUSY.bit.CCB2);                      // Wait for synchronization
+}
+
+void SetMotorOutput(uint16_t rpm)
+{
+  const float stepperHzToRPM = 1;                      //6.67hz runs the stepper at 1 RPM
+  SetFrequencyOutput(rpm * stepperHzToRPM);
 }
 
 void setup()
 {
-  //analogWriteSAH_Init();
-  Timer1.initialize(50);
-  Timer1.pwm(9, 1024/2);
-  Serial.begin(9600);
+  SetupTimer();
 }
 
 void loop()
 {
-  static int old_poti = 0;
-  int poti = analogRead(A7) / 10;
-  if (poti != old_poti) {
-    // period_us = 1 / khz * 1000
-    int period_us = (poti == 0) ? 0 : map(poti, 1, 102, 600, 50);
-    Timer1.initialize(period_us);
-    Timer1.pwm(9, 1024/2);
-    Serial.println(poti);
-    Serial.println(period_us);
-    old_poti = poti;
+  /*int newPotValue = analogRead(POT_PIN);
+  if (abs(newPotValue - potValue) > POT_JITTER_THRESHOLD)
+  {
+    potValue = newPotValue;
+    SetFrequencyOutput(map(potValue, 0, 1023, 0, 20000));
+  }*/
+  for(uint8_t i = 0; i <= 20; i++)
+  {
+    SetFrequencyOutput(i * 1000);
+    delay(10000);
   }
-  //Timer1.setPeriod();
-  //Timer1.setPeriod(50);
-  //Timer1.restart();
-
-#if 0
-  for (float frequency = 500; frequency < 3000; frequency = frequency + 1) {
-    float T = 1 / frequency * 1000000;
-    //Timer1.setPeriod(T);
-    delay(5);
+  for(uint8_t i = 20; i >= 0; i--)
+  {
+    SetFrequencyOutput(i * 1000);
+    delay(10000);
   }
-#endif
-}
\ No newline at end of file
+}