Added funtions to class RTC_PCF8563 for controlling the timer and int…

RTClib.cpp

@@ -1451,6 +1451,90 @@ DateTime RTC_PCF8563::now() {
   return DateTime(y, m, d, hh, mm, ss);
 }
 
+/**************************************************************************/
+/*!
+    @brief  Enable the Countdown Timer Interrupt on the PCF8563.
+*/
+/**************************************************************************/
+void RTC_PCF8563::enableCountdownTimer(PCF8563TimerClockFreq clkFreq, uint8_t numPeriods) {
+  // Set the countdown value (TIMER[7:0]) in the timer register
+  write_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER, numPeriods);
+
+  uint8_t timer_ctlreg = read_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL);
+  //write_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL, timer_ctlreg & ~0x03 | clkFreq);
+
+  // Sets the enable bit TE and the clock source bits TD[1:0] in the timer control register 
+  write_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL, (timer_ctlreg & ~PCF8563_TimerControl_TD) | clkFreq | PCF8563_TimerControl_TE);
+
+  // uint8_t timer_ctlreg = read_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL);
+  // //if (timer_ctlreg & (1 << 5)) {
+  //   write_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL, timer_ctlreg | (1 << 7));
+  // //}
+}
+
+/**************************************************************************/
+/*!
+    @brief  Disable the Countdown Timer on the PCF8563.
+    @details 
+*/
+/**************************************************************************/
+void RTC_PCF8563::disableCountdownTimer() {
+  // Leave compatible settings intact
+  uint8_t timer_ctlreg = read_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL);
+
+  // Reset the enable bit TE in the timer control register leaving the clock source bits TD[1:0] unchanged
+  write_i2c_register(PCF8563_ADDRESS, PCF8563_TIMER_CONTROL, timer_ctlreg & ~PCF8563_TimerControl_TE);
+}
+
+/**************************************************************************/
+/*!
+    @brief  Enable the interrupt for the countdown timer on the PCF8563.
+    @details 
+*/
+/**************************************************************************/
+void RTC_PCF8563::enableCountdownTimerInt(bool pulse) {
+  // Leave compatible settings intact
+  uint8_t ctlreg = read_i2c_register(PCF8563_ADDRESS, PCF8563_CONTROL_2);
+
+  // Set the counter interrupt enable bit TIE in the control status 2. Additionally clear any interrupt flags.
+  // Because the alarm and timer interrupt are tied to the interrupt signal both flags have to be cleared.
+  if(pulse) {
+    // sets the TI_TP bit in control status 2 register so that the generated interrupt is a pulse
+    ctlreg = (ctlreg | (PCF8563_CONTROL2_TI_TP | PCF8563_CONTROL2_TIE)) & ~(PCF8563_CONTROL2_AF | PCF8563_CONTROL2_TF);
+  } else {
+    // clear the TI_TP bit in control status 2 register. The value of INT is equal to the value 
+    // of the timer interrupt flag TF
+    ctlreg = (ctlreg | PCF8563_CONTROL2_TIE) & ~(PCF8563_CONTROL2_TI_TP | PCF8563_CONTROL2_AF | PCF8563_CONTROL2_TF);
+  }
+
+  write_i2c_register(PCF8563_ADDRESS, PCF8563_CONTROL_2, ctlreg);
+}
+
+/**************************************************************************/
+/*!
+    @brief  Disable the interrupt for the countdown timer on the PCF8563.
+    @details 
+*/
+/**************************************************************************/
+void RTC_PCF8563::disableCountdownTimerInt(void) {
+  // Leave compatible settings intact
+  uint8_t ctlreg = read_i2c_register(PCF8563_ADDRESS, PCF8563_CONTROL_2);
+
+  // Reset the enable bit TIE in the control status 2 register leaving other bits unchanged
+  write_i2c_register(PCF8563_ADDRESS, PCF8563_CONTROL_2, ctlreg & ~PCF8563_CONTROL2_TIE);
+}
+
+uint8_t RTC_PCF8563::getAndClearIntFlags(void) {
+  // Read control status register 2 which contains the interrupt flags
+  uint8_t ctlreg = read_i2c_register(PCF8563_ADDRESS, PCF8563_CONTROL_2);
+
+  // Clear the AF and TF interrupt flags in control status register 2
+  write_i2c_register(PCF8563_ADDRESS, PCF8563_CONTROL_2, ctlreg & ~12);
+
+  // Return the value of the control status 2 register masking out all bits except the TF and AF interrupt flags
+  return(ctlreg & (PCF8563_CONTROL2_AF | PCF8563_CONTROL2_TF));
+}
+
 /**************************************************************************/
 /*!
     @brief  Resets the STOP bit in register Control_1

RTClib.h

@@ -38,6 +38,8 @@ class TimeSpan;
 
 #define PCF8563_ADDRESS 0x51       ///< I2C address for PCF8563
 #define PCF8563_CLKOUTCONTROL 0x0D ///< CLKOUT control register
+#define PCF8563_TIMER_CONTROL 0x0E ///< Timer control register
+#define PCF8563_TIMER 0x0F         ///< Timer register
 #define PCF8563_CONTROL_1 0x00     ///< Control and status register 1
 #define PCF8563_CONTROL_2 0x01     ///< Control and status register 2
 #define PCF8563_VL_SECONDS 0x02    ///< register address for VL_SECONDS
@@ -410,6 +412,29 @@ class RTC_PCF8523 {
   void calibrate(Pcf8523OffsetMode mode, int8_t offset);
 };
 
+/** PCF8563 timer control register settings */
+enum PCF8563TimerControl {
+  PCF8563_TimerControl_TE = 128,
+  PCF8563_TimerControl_TD = 3
+};
+
+/** PCF8563 Timer clock source settings */
+enum PCF8563TimerClockFreq {
+  PCF8563_TimerClk4096kHz = 0x00, /**< 4096 kHz */
+  PCF8563_TimerClk64Hz = 0x01,    /**< 64 Hz */
+  PCF8563_TimerClk1Hz = 0x02,     /**< 1 Hz */
+  PCF8563_TimerClk1_60Hz = 0x03   /**< 1/60 Hz */
+};
+
+/** PCF8563 control status 2 register settings */
+enum PCF8563Control2 {
+  PCF8563_CONTROL2_TI_TP = 16,
+  PCF8563_CONTROL2_AF = 8,
+  PCF8563_CONTROL2_TF = 4,
+  PCF8563_CONTROL2_AIE = 2,
+  PCF8563_CONTROL2_TIE = 1
+};
+
 /** PCF8563 CLKOUT pin mode settings */
 enum Pcf8563SqwPinMode {
   PCF8563_SquareWaveOFF = 0x00,  /**< Off */
@@ -431,6 +456,11 @@ class RTC_PCF8563 {
   boolean lostPower(void);
   void adjust(const DateTime &dt);
   static DateTime now();
+  void enableCountdownTimer(PCF8563TimerClockFreq clkFreq, uint8_t numPeriods);
+  void disableCountdownTimer(void);
+  void enableCountdownTimerInt(bool pulse);
+  void disableCountdownTimerInt(void);
+  uint8_t getAndClearIntFlags(void);
   void start(void);
   void stop(void);
   uint8_t isrunning();