I2C PWM expander added from different Project

2024-11-16 16:42:29 +01:00
parent deccb3186c
commit f6608075ff
7 changed files with 327 additions and 0 deletions
@@ -0,0 +1,117 @@
+/**
+ * @file pwmExpanderPca9685.cpp
+ * @author Gustice
+ * @brief PWM-Expander PCA9685
+ *
+ * @copyright Copyright (c) 2024
+ */
+
+#include "pwmExpanderPca9685.hpp"
+#include "esp_log.h"
+#include <cmath>
+#include <unistd.h> // for usleepCommand
+
+enum Pca9685Codes {
+    PCA9685_MODE1 = 0x00,
+    PCA9685_MODE2 = 0x01,
+    Led0_ON_L = 0x06,
+    Led0_ON_H = 0x07,
+    Led0_OFF_L = 0x08,
+    Led0_OFF_H = 0x09,
+    // Led1_...Led15
+    AllLedON_L = 0xFA,
+    AllLedON_H = 0xFB,
+    AllLedOFF_L = 0xFC,
+    AllLedOFF_H = 0xFD,
+    PCA9685_PRESCALE = 0xFE,
+};
+
+enum Pca9685_Mode1Bits {
+    Mode1_Sleep = 0x10,
+    Mode1_AutoIncrement = 0x20,
+    Mode1_Restart = 0x80,
+};
+
+enum Pca9685_Mode2Bits {
+    Mode2_Invert = 0x10,
+    Mode2_OutDriver = 0x04,
+};
+
+constexpr int LedPortRegisterWidth = 2 * 2;
+constexpr int BitResolution = 12;
+constexpr int PwmMaxValue = 4096 - 1;
+
+PmwExpanderPca9685::PmwExpanderPca9685(I2cMaster &port, bool inverted, uint8_t address)
+    : _port(port, address, I2cMaster::Slave::_400k), _address(address & 0x7F) {
+    _data.resize(PwmChannels * LedPortRegisterWidth + 1);
+    reset();
+    setPwmFreq(400, inverted);
+}
+
+void PmwExpanderPca9685::reset(void) {
+    uint8_t mode = Mode1_Restart | Mode1_AutoIncrement;
+    write(PCA9685_MODE1, mode);
+    usleep(10000); // 10 ms
+}
+
+void PmwExpanderPca9685::setPwmFreq(float frequency, bool inverted) {
+    frequency *= 0.9f; // Correct for overshoot in the frequency setting (see issue #11).
+    float prescaleLevel = 25000000;
+    prescaleLevel /= PwmMaxValue;
+    prescaleLevel /= frequency;
+    prescaleLevel -= 1;
+
+    uint8_t prescale = (uint8_t)std::floor(prescaleLevel + 0.5f);
+    uint8_t oldMode = read(PCA9685_MODE1).value_or(0);
+    uint8_t newMode = (oldMode & 0x7F) | Mode1_Sleep; // sleep + Autoincrement
+    write(PCA9685_MODE1, newMode);                    // go to sleep
+    write(PCA9685_PRESCALE, prescale);                // set the prescaler
+    write(PCA9685_MODE1, oldMode);
+    if (inverted) {
+        write(PCA9685_MODE2, Mode2_OutDriver | Mode2_Invert);
+    } else {
+        write(PCA9685_MODE2, Mode2_OutDriver);
+    }
+
+    usleep(5000); // 5 ms
+    //  This sets the MODE1 register to turn on auto increment.
+    write(PCA9685_MODE1, oldMode | Mode1_Restart | Mode1_AutoIncrement);
+}
+
+void PmwExpanderPca9685::sendImage(GrayValues &grayValues) {
+    // Try to distribute load peaks over full duty cycle
+    // OUT1 ..###______###____###______###____###__..
+    // OUT2 ..__###______###____###______###____###..
+    // OUT3 ..____###______###______###____###_____..
+    // ...
+    int idx = 0;
+    int step = UINT16_MAX / 4 / PwmChannels; // max 90 deg phase shift
+    int curStep = step;
+    _data[idx++] = Led0_ON_L;
+    for (size_t i = 0; i < _count; i++) {
+        curStep = curStep + step;
+        uint16_t dur = (grayValues[i] + curStep) >> 4;
+        uint on = curStep >> 4;
+        // On-Cnt
+        _data[idx++] = (uint8_t)on;
+        _data[idx++] = (uint8_t)(on >> 8);
+        // Off-Cnt
+        _data[idx++] = (uint8_t)dur;
+        _data[idx++] = (uint8_t)(dur >> 8);
+    }
+    _port.writeTo(_data);
+}
+
+bool PmwExpanderPca9685::write(uint8_t reg, uint8_t word) {
+    std::vector<uint8_t> data{reg, word};
+    return _port.writeTo(data);
+}
+
+std::optional<uint8_t> PmwExpanderPca9685::read(uint8_t reg) {
+    auto value = _port.readFrom({reg}, 1);
+    if (value.size() == 0) {
+        return std::nullopt;
+    }
+
+    return {value.front()};
+}