braille_xr/hardware/braille_xr/libs/ESP32Servo/src/ESP32PWM.cpp
2024-01-28 08:53:21 -05:00

324 lines
9.3 KiB
C++

/*
* ESP32PWM.cpp
*
* Created on: Sep 22, 2018
* Author: hephaestus
*/
#include <ESP32PWM.h>
#include "esp32-hal-ledc.h"
// initialize the class variable ServoCount
int ESP32PWM::PWMCount = -1; // the total number of attached servos
bool ESP32PWM::explicateAllocationMode=false;
ESP32PWM * ESP32PWM::ChannelUsed[NUM_PWM]; // used to track whether a channel is in service
long ESP32PWM::timerFreqSet[4] = { -1, -1, -1, -1 };
int ESP32PWM::timerCount[4] = { 0, 0, 0, 0 };
// The ChannelUsed array elements are 0 if never used, 1 if in use, and -1 if used and disposed
// (i.e., available for reuse)
/**
* allocateTimer
* @param a timer number 0-3 indicating which timer to allocate in this library
* Switch to explicate allocation mode
*
*/
void ESP32PWM::allocateTimer(int timerNumber){
if(timerNumber<0 || timerNumber>3)
return;
if(ESP32PWM::explicateAllocationMode==false){
ESP32PWM::explicateAllocationMode=true;
for(int i=0;i<4;i++)
ESP32PWM::timerCount[i]=4;// deallocate all timers to start mode
}
ESP32PWM::timerCount[timerNumber]=0;
}
ESP32PWM::ESP32PWM() {
resolutionBits = 8;
pwmChannel = -1;
pin = -1;
myFreq = -1;
if (PWMCount == -1) {
for (int i = 0; i < NUM_PWM; i++)
ChannelUsed[i] = NULL; // load invalid data into the storage array of pin mapping
PWMCount = PWM_BASE_INDEX; // 0th channel does not work with the PWM system
}
}
ESP32PWM::~ESP32PWM() {
if (attached()) {
ledcDetachPin(pin);
}
deallocate();
}
double ESP32PWM::_ledcSetupTimerFreq(uint8_t chan, double freq,
uint8_t bit_num) {
return ledcSetup(chan, freq, bit_num);
}
int ESP32PWM::timerAndIndexToChannel(int timerNum, int index) {
int localIndex = 0;
for (int j = 0; j < NUM_PWM; j++) {
if (((j / 2) % 4) == timerNum) {
if (localIndex == index) {
return j;
}
localIndex++;
}
}
return -1;
}
int ESP32PWM::allocatenext(double freq) {
long freqlocal = (long) freq;
if (pwmChannel < 0) {
for (int i = 0; i < 4; i++) {
bool freqAllocated = ((timerFreqSet[i] == freqlocal)
|| (timerFreqSet[i] == -1));
if (freqAllocated && timerCount[i] < 4) {
if (timerFreqSet[i] == -1) {
//Serial.println("Starting timer "+String(i)+" at freq "+String(freq));
timerFreqSet[i] = freqlocal;
}
//Serial.println("Free channel timer "+String(i)+" at freq "+String(freq)+" remaining "+String(4-timerCount[i]));
timerNum = i;
for (int index=0; index<4; ++index)
{
int myTimerNumber = timerAndIndexToChannel(timerNum,index);
if ((myTimerNumber >= 0) && (!ChannelUsed[myTimerNumber]))
{
pwmChannel = myTimerNumber;
// Serial.println(
// "PWM on ledc channel #" + String(pwmChannel)
// + " using 'timer " + String(timerNum)
// + "' to freq " + String(freq) + "Hz");
ChannelUsed[pwmChannel] = this;
timerCount[timerNum]++;
PWMCount++;
myFreq = freq;
return pwmChannel;
}
}
} else {
// if(timerFreqSet[i]>0)
// Serial.println("Timer freq mismatch target="+String(freq)+" on timer "+String(i)+" was "+String(timerFreqSet[i]));
// else
// Serial.println("Timer out of channels target="+String(freq)+" on timer "+String(i)+" was "+String(timerCount[i]));
}
}
} else {
return pwmChannel;
}
Serial.println(
"ERROR All PWM timers allocated! Can't accomodate " + String(freq)
+ "Hz\r\nHalting...");
while (1)
;
}
void ESP32PWM::deallocate() {
if (pwmChannel < 0)
return;
// Serial.println("PWM deallocating LEDc #" + String(pwmChannel));
timerCount[getTimer()]--;
if (timerCount[getTimer()] == 0) {
timerFreqSet[getTimer()] = -1; // last pwn closed out
}
timerNum = -1;
attachedState = false;
ChannelUsed[pwmChannel] = NULL;
pwmChannel = -1;
PWMCount--;
}
int ESP32PWM::getChannel() {
if (pwmChannel < 0) {
Serial.println("FAIL! must setup() before using get channel!");
}
return pwmChannel;
}
double ESP32PWM::setup(double freq, uint8_t resolution_bits) {
checkFrequencyForSideEffects(freq);
resolutionBits = resolution_bits;
if (attached()) {
ledcDetachPin(pin);
double val = ledcSetup(getChannel(), freq, resolution_bits);
attachPin(pin);
return val;
}
return ledcSetup(getChannel(), freq, resolution_bits);
}
double ESP32PWM::getDutyScaled() {
return mapf((double) myDuty, 0, (double) ((1 << resolutionBits) - 1), 0.0,
1.0);
}
void ESP32PWM::writeScaled(double duty) {
write(mapf(duty, 0.0, 1.0, 0, (double) ((1 << resolutionBits) - 1)));
}
void ESP32PWM::write(uint32_t duty) {
myDuty = duty;
ledcWrite(getChannel(), duty);
}
void ESP32PWM::adjustFrequencyLocal(double freq, double dutyScaled) {
timerFreqSet[getTimer()] = (long) freq;
myFreq = freq;
if (attached()) {
ledcDetachPin(pin);
// Remove the PWM during frequency adjust
_ledcSetupTimerFreq(getChannel(), freq, resolutionBits);
writeScaled(dutyScaled);
ledcAttachPin(pin, getChannel()); // re-attach the pin after frequency adjust
} else {
_ledcSetupTimerFreq(getChannel(), freq, resolutionBits);
writeScaled(dutyScaled);
}
}
void ESP32PWM::adjustFrequency(double freq, double dutyScaled) {
if(dutyScaled<0)
dutyScaled=getDutyScaled();
writeScaled(dutyScaled);
for (int i = 0; i < timerCount[getTimer()]; i++) {
int pwm = timerAndIndexToChannel(getTimer(), i);
if (ChannelUsed[pwm] != NULL) {
if (ChannelUsed[pwm]->myFreq != freq) {
ChannelUsed[pwm]->adjustFrequencyLocal(freq,
ChannelUsed[pwm]->getDutyScaled());
}
}
}
}
double ESP32PWM::writeTone(double freq) {
for (int i = 0; i < timerCount[getTimer()]; i++) {
int pwm = timerAndIndexToChannel(getTimer(), i);
if (ChannelUsed[pwm] != NULL) {
if (ChannelUsed[pwm]->myFreq != freq) {
ChannelUsed[pwm]->adjustFrequencyLocal(freq,
ChannelUsed[pwm]->getDutyScaled());
}
write(1 << (resolutionBits-1)); // writeScaled(0.5);
}
}
return 0;
}
double ESP32PWM::writeNote(note_t note, uint8_t octave) {
const uint16_t noteFrequencyBase[12] = {
// C C# D Eb E F F# G G# A Bb B
4186, 4435, 4699, 4978, 5274, 5588, 5920, 6272, 6645, 7040, 7459,
7902 };
if (octave > 8 || note >= NOTE_MAX) {
return 0;
}
double noteFreq = (double) noteFrequencyBase[note]
/ (double) (1 << (8 - octave));
return writeTone(noteFreq);
}
uint32_t ESP32PWM::read() {
return ledcRead(getChannel());
}
double ESP32PWM::readFreq() {
return myFreq;
}
void ESP32PWM::attach(int p) {
pin = p;
attachedState = true;
}
void ESP32PWM::attachPin(uint8_t pin) {
if (hasPwm(pin)) {
attach(pin);
ledcAttachPin(pin, getChannel());
} else {
Serial.println(
"ERROR PWM channel unavailable on pin requested! " + String(pin)
#if defined(CONFIG_IDF_TARGET_ESP32S2)
+ "\r\nPWM available on: 1-21,26,33-42"
#elif defined(CONFIG_IDF_TARGET_ESP32S3)
+ "\r\nPWM available on: 1-21,35-45,47-48"
#elif defined(CONFIG_IDF_TARGET_ESP32C3)
+ "\r\nPWM available on: 1-10,18-21"
#else
+ "\r\nPWM available on: 2,4,5,12-19,21-23,25-27,32-33"
#endif
// Possible PWM GPIO pins on the ESP32-S3: 0(used by on-board button),1-21,35-45,47,48(used by on-board LED)
// Possible PWM GPIO pins on the ESP32-C3: 0(used by on-board button),1-7,8(used by on-board LED),9-10,18-21
);
return;
}
//Serial.print(" on pin "+String(pin));
}
void ESP32PWM::attachPin(uint8_t pin, double freq, uint8_t resolution_bits) {
if (hasPwm(pin))
setup(freq, resolution_bits);
attachPin(pin);
}
void ESP32PWM::detachPin(int pin) {
ledcDetachPin(pin);
deallocate();
}
/* Side effects of frequency changes happen because of shared timers
*
* LEDC Chan to Group/Channel/Timer Mapping
** ledc: 0 => Group: 0, Channel: 0, Timer: 0
** ledc: 1 => Group: 0, Channel: 1, Timer: 0
** ledc: 2 => Group: 0, Channel: 2, Timer: 1
** ledc: 3 => Group: 0, Channel: 3, Timer: 1
** ledc: 4 => Group: 0, Channel: 4, Timer: 2
** ledc: 5 => Group: 0, Channel: 5, Timer: 2
** ledc: 6 => Group: 0, Channel: 6, Timer: 3
** ledc: 7 => Group: 0, Channel: 7, Timer: 3
** ledc: 8 => Group: 1, Channel: 0, Timer: 0
** ledc: 9 => Group: 1, Channel: 1, Timer: 0
** ledc: 10 => Group: 1, Channel: 2, Timer: 1
** ledc: 11 => Group: 1, Channel: 3, Timer: 1
** ledc: 12 => Group: 1, Channel: 4, Timer: 2
** ledc: 13 => Group: 1, Channel: 5, Timer: 2
** ledc: 14 => Group: 1, Channel: 6, Timer: 3
** ledc: 15 => Group: 1, Channel: 7, Timer: 3
*/
bool ESP32PWM::checkFrequencyForSideEffects(double freq) {
allocatenext(freq);
for (int i = 0; i < timerCount[getTimer()]; i++) {
int pwm = timerAndIndexToChannel(getTimer(), i);
if (pwm == pwmChannel)
continue;
if (ChannelUsed[pwm] != NULL)
if (ChannelUsed[pwm]->getTimer() == getTimer()) {
double diff = abs(ChannelUsed[pwm]->myFreq - freq);
if (abs(diff) > 0.1) {
Serial.println(
"\tWARNING PWM channel " + String(pwmChannel)
+ " shares a timer with channel "
+ String(pwm) + "\n"
"\tchanging the frequency to "
+ String(freq)
+ " Hz will ALSO change channel "
+ String(pwm)
+ " \n\tfrom its previous frequency of "
+ String(ChannelUsed[pwm]->myFreq) + " Hz\n"
" ");
ChannelUsed[pwm]->myFreq = freq;
}
}
}
return true;
}
ESP32PWM* pwmFactory(int pin) {
for (int i = 0; i < NUM_PWM; i++)
if (ESP32PWM::ChannelUsed[i] != NULL) {
if (ESP32PWM::ChannelUsed[i]->getPin() == pin)
return ESP32PWM::ChannelUsed[i];
}
return NULL;
}