🚧 WIP, dsx - Add read and sensor id funcs

Author: brentru

src/components/ds18x20/controller.cpp

@@ -29,15 +29,23 @@ bool DS18X20Controller::Handle_Ds18x20Add(pb_istream_t *stream) {
 
   // Initialize the DS18X20Hardware object
   DS18X20Hardware new_dsx_driver(pin_name);
-  new_dsx_driver.setResolution(
-      _DS18X20_model->GetDS18x20AddMsg()->sensor_resolution);
+  // Attempt to get the sensor's ID on the OneWire bus to show it's been init'd
+  bool is_initialized = new_dsx_driver.GetSensor();
+  if (!is_initialized) {
+    WS_DEBUG_PRINTLN("Sensor found on OneWire bus and initialized");
+    // Set the sensor's resolution
+    new_dsx_driver.setResolution(
+        _DS18X20_model->GetDS18x20AddMsg()->sensor_resolution);
 
-  // Add the DS18X20Hardware object to the vector of hardware objects
-  _DS18X20_pins.push_back(new_dsx_driver);
+    // Add the DS18X20Hardware object to the vector of hardware objects
+    _DS18X20_pins.push_back(new_dsx_driver);
+  } else {
+    WS_DEBUG_PRINTLN("ERROR: Unable to get sensor ID, sensor not initialized");
+  }
 
   // Encode and publish a Ds18x20Added message back to the broker
   if (!_DS18X20_model->EncodeDS18x20Added(
-          _DS18X20_model->GetDS18x20AddMsg()->onewire_pin, true)) {
+          _DS18X20_model->GetDS18x20AddMsg()->onewire_pin, is_initialized)) {
     WS_DEBUG_PRINTLN("ERROR: Unable to encode Ds18x20Added message");
     return false;
   }
@@ -51,3 +59,19 @@ bool DS18X20Controller::Handle_Ds18x20Add(pb_istream_t *stream) {
 
   return true;
 }
+
+void DS18X20Controller::update() {
+  // Bail out if there are no OneWire pins to poll
+  if (_DS18X20_pins.size() == 0)
+    return;
+
+  // Iterate through the vector
+  for (uint8_t i = 0; i < _DS18X20_pins.size(); i++) {
+    // Create a temporary DS18X20Hardware driver
+    DS18X20Hardware *temp_dsx_driver = &_DS18X20_pins[i];
+    // Check if the driver's timer has expired
+    if (temp_dsx_driver->IsTimerExpired())
+      return;
+    // TODO: Poll the sensor
+  }
+}

src/components/ds18x20/controller.h

@@ -33,6 +33,8 @@ class DS18X20Controller {
   ~DS18X20Controller();
   // Routing
   bool Handle_Ds18x20Add(pb_istream_t *stream);
+  // Polling
+  void update();
 
 private:
   DS18X20Model *_DS18X20_model; ///< ds18x20 model

src/components/ds18x20/hardware.cpp

@@ -15,11 +15,17 @@
 #include "hardware.h"
 
 DS18X20Hardware::DS18X20Hardware(uint8_t onewire_pin) : _drv_therm(_ow) {
+  // Initialize the OneWire bus object
   new (&_ow) OneWireNg_CurrentPlatform(onewire_pin, false);
 }
 
 DS18X20Hardware::~DS18X20Hardware() { delete &_ow; }
 
+bool DS18X20Hardware::GetSensor() {
+  OneWireNg::ErrorCode ec = _ow->readSingleId(_sensorId);
+  return ec == OneWireNg::EC_SUCCESS;
+}
+
 void DS18X20Hardware::setResolution(int resolution) {
   // Set the resolution of the DS18X20 sensor driver
   switch (resolution) {
@@ -49,4 +55,34 @@ void DS18X20Hardware::setResolution(int resolution) {
   // memory and will be lost after power unplug. Therefore store the
   // configuration permanently in sensors EEPROM.
   _drv_therm.copyScratchpadAll(false);
+}
+
+bool DS18X20Hardware::IsTimerExpired() {
+  // Get the current time in milliseconds and compare it to the last time
+  // the sensor was polled
+  ulong cur_time = millis();
+  return millis() - _prv_period > _period;
+}
+
+OneWireNg::ErrorCode DS18X20Hardware::ReadTemperatureC() {
+  // Start temperature conversion for the first identified sensor on the OneWire
+  // bus
+  OneWireNg::ErrorCode ec =
+      _drv_therm.convertTemp(_sensorId, DSTherm::MAX_CONV_TIME, false);
+  if (ec != OneWireNg::EC_SUCCESS)
+    return ec;
+
+  // Scratchpad placeholder is static to allow reuse of the associated
+  // sensor id while reissuing readScratchpadSingle() calls.
+  // Note, due to its storage class the placeholder is zero initialized.
+  static Placeholder<DSTherm::Scratchpad> scrpd;
+  ec = _drv_therm.readScratchpadSingle(scrpd);
+  if (ec != OneWireNg::EC_SUCCESS)
+    return ec;
+
+  // Read the temperature from the sensor
+  long temp = scrpd->getTemp2();
+  _temp_c = temp / 16.0; // Convert from 16-bit int to float
+
+  return ec;
 }

src/components/ds18x20/hardware.h

@@ -30,15 +30,21 @@ class DS18X20Hardware {
 public:
   DS18X20Hardware(uint8_t onewire_pin);
   ~DS18X20Hardware();
+  bool GetSensor();
+  OneWireNg::ErrorCode DS18X20Hardware::ReadTemperatureC();
   void setResolution(int resolution);
+  bool IsTimerExpired();
 
 private:
   // NOTE: We are going to try definining a vector of DS18X20Hardware objects
   // iwthin the controller so instead of a struct, these are all assigned to
   // this class
   Placeholder<OneWireNg_CurrentPlatform> _ow; ///< OneWire bus object
-  DSTherm _drv_therm;                         ///< DS18X20 driver object
+  OneWireNg::Id _sensorId;
+  DSTherm _drv_therm;              ///< DS18X20 driver object
   DSTherm::Resolution _resolution; ///< Resolution of the DS18X20 sensor
+  float _temp_c;
+  float _temp_f;
   // From the PB model
   uint8_t onewire_pin; ///< Pin utilized by the OneWire bus, used for addressing
   float _period;       ///< The desired period to read the sensor, in seconds