T4 timer

.gitignore

@@ -236,3 +236,4 @@ pip-log.txt
 *.cbp
 *.layout
 *.save-failed
+*.cmd

ADC.cpp

@@ -187,6 +187,12 @@ const uint8_t ADC::sc1a2channelADC0[]= { // new version, gives directly the pin
     0, 66, 0, 0, 70, 0, 0, 0, // 22-29
     0 // 31 means disabled, but just in case
 };
+#elif defined(ADC_TEENSY_4)
+const uint8_t ADC::sc1a2channelADC0[]= { // new version, gives directly the pin number
+    21, 24, 25, 0, 0, 19, 18, 14, 15, 0, 0, 17, 16, 22,
+    23, 20, 0, 0, 0, 0, 0, 0, //14-21
+    0, 0, 0, 0, 0, 0    //22-27
+};
 #endif // defined
 
 ///////// ADC1
@@ -204,6 +210,12 @@ const uint8_t ADC::sc1a2channelADC1[]= { // new version, gives directly the pin
     0, 67, 0, 0, 0, 0, 0, 0, // 22-29.
     0
 };
+#elif defined(ADC_TEENSY_4)
+const uint8_t ADC::sc1a2channelADC1[]= { // new version, gives directly the pin number
+    21, 0, 0, 26, 27, 19, 18, 14, 15, 0, 0, 17, 16, 22, // 0-13
+    23, 20, 0, 0, 0, 0, 0, 0, //14-21
+    0, 0, 0, 0, 0, 0    //22-27
+};
 #endif
 
 

ADC_Module.cpp

@@ -58,7 +58,11 @@ ADC_Module::ADC_Module(uint8_t ADC_number,
         , PDB0_CHnC1(ADC_num? PDB0_CH1C1 : PDB0_CH0C1)
         #endif
         #if defined(ADC_TEENSY_4)
-        , IRQ_ADC(ADC_num? IRQ_NUMBER_t::IRQ_ADC2 : IRQ_NUMBER_t::IRQ_ADC1)
+        , XBAR_IN(ADC_num? XBARA1_IN_QTIMER4_TIMER3 : XBARA1_IN_QTIMER4_TIMER0)
+        , XBAR_OUT(ADC_num? XBARA1_OUT_ADC_ETC_TRIG10 : XBARA1_OUT_ADC_ETC_TRIG00)
+        , QTIMER4_INDEX(ADC_num? 3 : 0)
+        , ADC_ETC_TRIGGER_INDEX(ADC_num? 4 : 0) 
+        , IRQ_ADC(ADC_num? IRQ_NUMBER_t::IRQ_ADC2 : IRQ_NUMBER_t::IRQ_ADC1)        
         #elif ADC_NUM_ADCS==2
         // IRQ_ADC0 and IRQ_ADC1 aren't consecutive in Teensy 3.6
         // fix by SB, https://github.com/pedvide/ADC/issues/19
@@ -1473,3 +1477,104 @@ uint32_t ADC_Module::getPDBFrequency() {
 }
 
 #endif
+
+#if ADC_USE_TIMER && !ADC_USE_PDB
+#if defined(ADC_TEENSY_4) // only supported by Teensy 4...
+// try to use some teensy core functions...
+// mainly out of pwm.c
+extern "C" {
+    extern void xbar_connect(unsigned int input, unsigned int output);
+    extern void quadtimer_init(IMXRT_TMR_t *p);
+    extern void quadtimerWrite(IMXRT_TMR_t *p, unsigned int submodule, uint16_t val);
+    extern void quadtimerFrequency(IMXRT_TMR_t *p, unsigned int submodule, float frequency);
+}
+
+void ADC_Module::startTimer(uint32_t freq) {
+    // First lets setup the XBAR
+    CCM_CCGR2 |= CCM_CCGR2_XBAR1(CCM_CCGR_ON);   //turn clock on for xbara1
+    xbar_connect(XBAR_IN, XBAR_OUT);
+
+    // Update the ADC
+    uint8_t adc_pin_channel = adc_regs.HC0 & 0x1f; // remember the trigger that was set
+    setHardwareTrigger();   // set the hardware trigger
+    adc_regs.HC0 = (adc_regs.HC0 & ~0x1f) | 16;      // ADC_ETC channel remember other states...
+    singleMode();           // make sure continuous is turned off as you want the trigger to di it. 
+
+    // setup adc_etc - BUGBUG have not used the preset values yet. 
+    if ( IMXRT_ADC_ETC.CTRL & ADC_ETC_CTRL_SOFTRST) {// SOFTRST
+        // Soft reset 
+        atomic::clearBitFlag(IMXRT_ADC_ETC.CTRL, ADC_ETC_CTRL_SOFTRST);
+        delay(5); // give some time to be sure it is init
+    }
+    if (ADC_num == 0) { // BUGBUG - in real code, should probably know we init ADC or not..
+        IMXRT_ADC_ETC.CTRL |= 
+            (ADC_ETC_CTRL_TSC_BYPASS | ADC_ETC_CTRL_DMA_MODE_SEL | ADC_ETC_CTRL_TRIG_ENABLE(1 << ADC_ETC_TRIGGER_INDEX)); // 0x40000001;  // start with trigger 0
+        IMXRT_ADC_ETC.TRIG[ADC_ETC_TRIGGER_INDEX].CTRL = ADC_ETC_TRIG_CTRL_TRIG_CHAIN(0);   // chainlength -1 only us
+        IMXRT_ADC_ETC.TRIG[ADC_ETC_TRIGGER_INDEX].CHAIN_1_0 =
+            ADC_ETC_TRIG_CHAIN_IE0(1) /*| ADC_ETC_TRIG_CHAIN_B2B0 */
+            | ADC_ETC_TRIG_CHAIN_HWTS0(1) | ADC_ETC_TRIG_CHAIN_CSEL0(adc_pin_channel) ;
+
+        if (interrupts_enabled) {
+            // Not sure yet? 
+        }
+        if (adc_regs.GC && ADC_GC_DMAEN) {
+            IMXRT_ADC_ETC.DMA_CTRL |= ADC_ETC_DMA_CTRL_TRIQ_ENABLE(ADC_ETC_TRIGGER_INDEX);
+        }
+    } else {
+        // This is our second one... Try second trigger? 
+        // Remove the BYPASS?
+        IMXRT_ADC_ETC.CTRL &= ~(ADC_ETC_CTRL_TSC_BYPASS); // 0x40000001;  // start with trigger 0
+        IMXRT_ADC_ETC.CTRL |= ADC_ETC_CTRL_DMA_MODE_SEL | ADC_ETC_CTRL_TRIG_ENABLE(1 << ADC_ETC_TRIGGER_INDEX);     // Add trigger 
+        IMXRT_ADC_ETC.TRIG[ADC_ETC_TRIGGER_INDEX].CTRL = ADC_ETC_TRIG_CTRL_TRIG_CHAIN(0);   // chainlength -1 only us
+        IMXRT_ADC_ETC.TRIG[ADC_ETC_TRIGGER_INDEX].CHAIN_1_0 =
+          ADC_ETC_TRIG_CHAIN_IE0(1) /*| ADC_ETC_TRIG_CHAIN_B2B0 */
+          | ADC_ETC_TRIG_CHAIN_HWTS0(1) | ADC_ETC_TRIG_CHAIN_CSEL0(adc_pin_channel) ;
+
+        if (adc_regs.GC && ADC_GC_DMAEN) {
+            IMXRT_ADC_ETC.DMA_CTRL |= ADC_ETC_DMA_CTRL_TRIQ_ENABLE(ADC_ETC_TRIGGER_INDEX);
+        }
+    }
+
+    // Now init the QTimer.
+    // Extracted from quadtimer_init in pwm.c but only the one channel...
+    // Maybe see if we have to do this every time we call this.  But how often is that? 
+    IMXRT_TMR4.CH[QTIMER4_INDEX].CTRL = 0; // stop timer
+    IMXRT_TMR4.CH[QTIMER4_INDEX].CNTR = 0;
+    IMXRT_TMR4.CH[QTIMER4_INDEX].SCTRL = TMR_SCTRL_OEN | TMR_SCTRL_OPS | TMR_SCTRL_VAL | TMR_SCTRL_FORCE;
+    IMXRT_TMR4.CH[QTIMER4_INDEX].CSCTRL = TMR_CSCTRL_CL1(1) | TMR_CSCTRL_ALT_LOAD;
+    // COMP must be less than LOAD - otherwise output is always low
+    IMXRT_TMR4.CH[QTIMER4_INDEX].LOAD = 24000;   // low time  (65537 - x) - 
+    IMXRT_TMR4.CH[QTIMER4_INDEX].COMP1 = 0;  // high time (0 = always low, max = LOAD-1)
+    IMXRT_TMR4.CH[QTIMER4_INDEX].CMPLD1 = 0;
+    IMXRT_TMR4.CH[QTIMER4_INDEX].CTRL = TMR_CTRL_CM(1) | TMR_CTRL_PCS(8) |
+        TMR_CTRL_LENGTH | TMR_CTRL_OUTMODE(6);
+
+    quadtimerFrequency(&IMXRT_TMR4, QTIMER4_INDEX, freq);
+    quadtimerWrite(&IMXRT_TMR4, QTIMER4_INDEX, 5);
+
+}
+
+//! Stop the PDB
+void ADC_Module::stopTimer() {
+    quadtimerWrite(&IMXRT_TMR4, QTIMER4_INDEX, 0);  
+    setSoftwareTrigger();
+
+
+}
+
+//! Return the PDB's frequency
+uint32_t ADC_Module::getTimerFrequency() {
+    // Can I reverse the calculations of quad timer set frequency?
+    uint32_t high = IMXRT_TMR4.CH[QTIMER4_INDEX].CMPLD1; 
+    uint32_t low = 65537 - IMXRT_TMR4.CH[QTIMER4_INDEX].LOAD;
+    uint32_t highPlusLow = high + low;   // 
+    if (highPlusLow == 0) return 0; // 
+
+    uint8_t pcs = (IMXRT_TMR4.CH[QTIMER4_INDEX].CTRL >> 9) & 0x7;
+    uint32_t freq = (F_BUS_ACTUAL >> pcs)/highPlusLow;
+    //Serial.printf("ADC_Module::getTimerFrequency H:%u L:%u H+L=%u pcs:%u freq:%u\n", high, low, highPlusLow, pcs, freq);
+    return freq;
+}
+
+#endif // Teensy 4
+#endif // ADC_USE_TIMER

ADC_Module.h

@@ -501,7 +501,7 @@ class ADC_Module {
 
 
     //////////// PDB ////////////////
-    //// Only works for Teensy 3.0 and 3.1, not LC (it doesn't have PDB)
+    //// Only works for Teensy 3.x not LC nor tensy 4.0 (they don't have PDB)
     #if ADC_USE_PDB
 
     //! Start PDB triggering the ADC at the frequency
@@ -518,6 +518,37 @@ class ADC_Module {
     uint32_t getPDBFrequency();
     #endif
 
+    //////////// TIMER ////////////////
+    //// Only works for Teensy T3.x and T4 (not LC) on T3.x (If USE_PDB is defined just calls back to PDB)
+    #if ADC_USE_TIMER
+        #if ADC_USE_PDB
+        void startTimer(uint32_t freq) __attribute__((always_inline)) { startPDB(freq); }
+
+        //! Stop the PDB
+        void stopTimer() __attribute__((always_inline)) { stopPDB(); }
+
+        //! Return the PDB's frequency
+        uint32_t getTimerFrequency() __attribute__((always_inline)) { return getPDBFrequency(); }
+
+
+        #else
+        //! Start a timer to trigger the ADC at the frequency
+        /** Call startSingleRead or startSingleDifferential on the pin that you want to measure before calling this function.
+        *   See the example adc_pdb.ino.
+        *   \param freq is the frequency of the ADC conversion, it can't be lower that 1 Hz
+        */
+        void startTimer(uint32_t freq);
+
+        //! Stop the timer
+        void stopTimer();
+
+        //! Return the timer's frequency
+        uint32_t getTimerFrequency();
+        #endif
+
+    #endif
+
+
 
     //////// OTHER STUFF ///////////
 
@@ -670,7 +701,12 @@ class ADC_Module {
     #if ADC_USE_PDB
     reg PDB0_CHnC1; // PDB channel 0 or 1
     #endif
-
+    #ifdef ADC_TEENSY_4
+    uint8_t XBAR_IN;
+    uint8_t XBAR_OUT;
+    uint8_t QTIMER4_INDEX;
+    uint8_t ADC_ETC_TRIGGER_INDEX;    
+    #endif
     const IRQ_NUMBER_t IRQ_ADC; // IRQ number
 
 protected: