/* Example for triggering the ADC with PDB
* Valid for Teensy 3.0 and 3.1, not LC
*
* In Teensyduino version 1.41 and above there are new forms of the following calls.
* (conversionspeed can be VERY_LOW_SPEED, LOW_SPEED, MED_SPEED, HIGH_SPEED_16BITS, HIGH_SPEED or VERY_HIGH_SPEED)
* (samplingspeed can be VERY_LOW_SPEED, LOW_SPEED, MED_SPEED, HIGH_SPEED or VERY_HIGH_SPEED)
* (adcnumber can be ADC_0 or ADC_1)
* Obsolete forms:
* adc->setConversionSpeed(conversionspeed, adcnumber);
* adc->setSamplingSpeed(samplingspeed, adcnumber);
* Current forms:
* adc->setConversionSpeed(ADC_CONVERSION_SPEED::conversionspeed, adcnumber);
* adc->setSamplingSpeed(ADC_SAMPLING_SPEED::samplingspeed, adcnumber);
*
* Serial monitor commands
* v [Enter] print values
* s Hz [Enter] start pdb, frequency in Hz
* p [Enter] pdb stats
*/
#include <ADC.h>
const int readPin = A9; // ADC0
const int readPin2 = A2; // ADC1
ADC *adc = new ADC(); // adc object;
void setup() {
pinMode(LED_BUILTIN, OUTPUT);
pinMode(readPin, INPUT);
pinMode(readPin2, INPUT);
Serial.begin(9600);
Serial.println("Begin setup");
///// ADC0 ////
// reference can be ADC_REFERENCE::REF_3V3, ADC_REFERENCE::REF_1V2 (not for Teensy LC) or ADC_REF_EXT.
//adc->setReference(ADC_REFERENCE::REF_1V2, ADC_0); // change all 3.3 to 1.2 if you change the reference to 1V2
adc->setAveraging(1); // set number of averages
adc->setResolution(8); // set bits of resolution
// it can be VERY_LOW_SPEED, LOW_SPEED, MED_SPEED, HIGH_SPEED_16BITS, HIGH_SPEED or VERY_HIGH_SPEED
// see the documentation for more information
adc->setConversionSpeed(ADC_CONVERSION_SPEED::VERY_HIGH_SPEED, ADC_0); // change the conversion speed
// it can be VERY_LOW_SPEED, LOW_SPEED, MED_SPEED, HIGH_SPEED or VERY_HIGH_SPEED
adc->setSamplingSpeed(ADC_SAMPLING_SPEED::VERY_HIGH_SPEED, ADC_0); // change the sampling speed
adc->enableInterrupts(ADC_0); // it's necessary to enable interrupts for PDB to work (why?)
adc->analogRead(readPin, ADC_0); // call this to setup everything before the pdb starts
////// ADC1 /////
#if ADC_NUM_ADCS>1
adc->setAveraging(32, ADC_1); // set number of averages
adc->setResolution(16, ADC_1); // set bits of resolution
adc->setConversionSpeed(ADC_CONVERSION_SPEED::VERY_LOW_SPEED, ADC_1); // change the conversion speed
adc->setSamplingSpeed(ADC_SAMPLING_SPEED::VERY_LOW_SPEED, ADC_1); // change the sampling speed
adc->enableInterrupts(ADC_1);
adc->analogRead(readPin2, ADC_1); // call this to setup everything before the pdb starts
#endif
Serial.println("End setup");
}
char c=0;
int value;
int value2;
void loop() {
if (Serial.available()) {
c = Serial.read();
if(c=='v') { // value
Serial.print("Value ADC0: ");
value = (uint16_t)adc->analogReadContinuous(ADC_0); // the unsigned is necessary for 16 bits, otherwise values larger than 3.3/2 V are negative!
Serial.println(value*3.3/adc->getMaxValue(ADC_0), DEC);
#if ADC_NUM_ADCS>1
Serial.print("Value ADC1: ");
value2 = (uint16_t)adc->analogReadContinuous(ADC_1); // the unsigned is necessary for 16 bits, otherwise values larger than 3.3/2 V are negative!
Serial.println(value2*3.3/adc->getMaxValue(ADC_1), DEC);
#endif
} else if(c=='s') { // start pdb, before pressing enter write the frequency in Hz
uint32_t freq = Serial.parseInt();
Serial.print("Start pdb with frequency ");
Serial.print(freq);
Serial.println(" Hz.");
adc->adc0->stopPDB();
adc->adc0->startPDB(freq); //frequency in Hz
#if ADC_NUM_ADCS>1
adc->adc1->stopPDB();
adc->adc1->startPDB(freq); //frequency in Hz
#endif
} else if(c=='p') { // pbd stats
Serial.print("Prescaler:");
Serial.println( (PDB0_SC&0x7000)>>12 , HEX);
Serial.print("Mult:");
Serial.println( (PDB0_SC&0xC)>>2, HEX);
}
}
/* fail_flag contains all possible errors,
They are defined in ADC_Module.h as
ADC_ERROR_OTHER
ADC_ERROR_CALIB
ADC_ERROR_WRONG_PIN
ADC_ERROR_ANALOG_READ
ADC_ERROR_COMPARISON
ADC_ERROR_ANALOG_DIFF_READ
ADC_ERROR_CONT
ADC_ERROR_CONT_DIFF
ADC_ERROR_WRONG_ADC
ADC_ERROR_SYNCH
You can compare the value of the flag with those masks to know what's the error.
*/
if(adc->adc0->fail_flag) {
Serial.print("ADC0 error flags: 0x");
Serial.println(adc->adc0->fail_flag, HEX);
if(adc->adc0->fail_flag == ADC_ERROR_COMPARISON) {
adc->adc0->fail_flag &= ~ADC_ERROR_COMPARISON; // clear that error
Serial.println("Comparison error in ADC0");
}
}
#if ADC_NUM_ADCS>1
if(adc->adc1->fail_flag) {
Serial.print("ADC1 error flags: 0x");
Serial.println(adc->adc1->fail_flag, HEX);
if(adc->adc1->fail_flag == ADC_ERROR_COMPARISON) {
adc->adc1->fail_flag &= ~ADC_ERROR_COMPARISON; // clear that error
Serial.println("Comparison error in ADC1");
}
}
#endif
//digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN));
//delay(100);
}
// If you enable interrupts make sure to call readSingle() to clear the interrupt.
void adc0_isr() {
adc->adc0->readSingle();
//digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN) );
}
#if ADC_NUM_ADCS>1
void adc1_isr() {
adc->adc1->readSingle();
digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN) );
}
#endif
// pdb interrupt is enabled in case you need it.
void pdb_isr(void) {
PDB0_SC &=~PDB_SC_PDBIF; // clear interrupt
//digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN) );
}
