Comment code

include/sta/MS5607.hpp

@@ -6,8 +6,10 @@
 #include<sta/stm32/delay.hpp>
 
 namespace sta {
+    // Class to represent a MS5607 pressure sensor which is used with SPI
     class MS5607 {
     public:
+        // Different OSR levels for the sensor
         enum OsrLevel {
             _256 = 0,
             _512 = 1,
@@ -18,17 +20,25 @@ namespace sta {
 
         MS5607(SpiDevice* device, OsrLevel osr=OsrLevel::_1024);
 
+        // Getter for pressure
         int32_t getPressure();
+        // Getter for temperature
         int32_t getTemperature();
 
-        void changeOsrLevel(OsrLevel newOsr) { this->osr_ = newOsr; }
+        void changeOsrLevel(OsrLevel newOsr) { 
+            // Don't I need to write this to the sensor?
+            this->osr_ = newOsr; 
+        }
 
     private:
+        // STA internal object for SPi abstraction
         SpiDevice* device_;
         OsrLevel osr_;
 
+        // 6 Different constants; Includes Offsets, references etc.
         uint16_t sens, off, tcs, tco, t_ref, tempsens;
         
+        // All possible commands to send to the sensor
         enum Operations {
             RESET = 0x1E,
             READ_PROM = 0xA2,
@@ -37,17 +47,18 @@ namespace sta {
             ADC_RESULT = 0x00
         };
 
+        // Request pure ADC converted values from the sensor
+        // Calculations with offset required
         uint32_t readPressure();
         uint32_t readTemp();
+        // Calculate pure ADC values to final pressure/temperature values
         int32_t calculatePressure(uint32_t d1, int32_t dT);
         int32_t calculateTemperature(uint32_t d2);
 
         void reset();
         void readPROM();
 
-        // Take first bytes from buffer, swap them and store those in uint16_t
-        static uint16_t uint_8BufferTouint16_t(uint8_t* buffer);
-
+        // Constants for waiting
         const char RESET_DELAY = 2800; // in uS
         const char ADC_DELAY = 8220; // in uS; not sure if thats correct since the datasheet doesn't say anything explicitly
     };

src/MS5607.cpp

@@ -5,11 +5,14 @@ namespace sta {
         this->device_ = device;
         this->osr_ = level;
 
+        // Reset device on start-up
         this->reset();
+        // Read the PROM e.g. constants
         this->readPROM();
     }
 
     int32_t MS5607::getPressure() {
+        // Get pure ADC value from the sensor
         uint32_t d1 = readPressure();
 
         // Since pressure is temp-dependant, temperature needs to be polled
@@ -22,22 +25,29 @@ namespace sta {
     }
 
     uint32_t MS5607::readPressure() {
+        // Request pressure value conversion
         this->device_->beginTransmission();
         this->device_->transfer(MS5607::Operations::D1_CONVERSION + 2*this->osr_);
         this->device_->endTransmission();
 
+        // Wait for ADC to finish
         delayUs(MS5607::ADC_DELAY);
-        uint8_t d1Arr[3];
 
+        // Request read of ADC value
+        uint8_t d1Arr[3];
         this->device_->beginTransmission();
         this->device_->receive(d1Arr, 3);
         this->device_->endTransmission();
 
+        // Convert into best possible type
         uint32_t res = 0;
         res |= d1Arr[0] | (d1Arr[1] << 8) | (d1Arr[2] << 16);
         return res;
     }
 
+    // Calculations from the Datasheet
+    // Probably problems with type conversions
+    // If we used Rust...
     int32_t MS5607::calculatePressure(uint32_t d1, int32_t dT) {
         int64_t offset = (this->off << 17) + ((this->tco * dT) >> 6);
         int64_t sensitivity = (this->sens << 16) + ((this->tcs * dT) >> 7);
@@ -46,28 +56,36 @@ namespace sta {
     }
 
     int32_t MS5607::getTemperature() {
+        // Get pure ADC value from the sensor
         uint32_t d2 = readTemp();
 
-        calculateTemperature(d2);
+        return calculateTemperature(d2);
     }
 
     uint32_t MS5607::readTemp() {
+        // Request ADC conversion of temperature
         this->device_->beginTransmission();
         this->device_->transfer(MS5607::Operations::D2_CONVERSION + 2*this->osr_);
         this->device_->endTransmission();
 
+        // Wait for ADC to finish
         delayUs(MS5607::ADC_DELAY);
-        uint8_t d2Arr[3];
 
+        // Request ADC readout
+        uint8_t d2Arr[3];
         this->device_->beginTransmission();
         this->device_->receive(d2Arr, 3);
         this->device_->endTransmission();
 
+        // Convert into best possible type
         uint32_t res = 0;
         res |= d2Arr[0] | d2Arr[1] << 8 | d2Arr[2] << 16;
         return res;
     }
 
+    // Calculations from the Datasheet
+    // Probably problems with type conversions
+    // If we used Rust...
     int32_t MS5607::calculateTemperature(uint32_t d2) {
         int32_t dT = d2 - (this->t_ref << 8);
         int32_t temp = 2000 + ((dT * this->tempsens) >> 23);
@@ -78,6 +96,7 @@ namespace sta {
         return temp;
     } 
 
+    // Reset sequence as described in datasheet
     void MS5607::reset() {
         this->device_->beginTransmission();
         this->device_->transfer(MS5607::Operations::RESET);
@@ -85,6 +104,10 @@ namespace sta {
         delayUs(MS5607::RESET_DELAY);
     }
 
+    // Read all constants from the PROM
+    // May be moved to be called in reset() function in future
+    // Request value x -> Read value x; Then request value y etc.
+    // Could be optimized; Not as important since only needed once at start-up
     void MS5607::readPROM() {
         this->device_->beginTransmission();
 
@@ -121,7 +144,10 @@ namespace sta {
         this->device_->endTransmission();
     }
 
-    uint16_t MS5607::uint_8BufferTouint16_t(uint8_t* buffer) {
+    // Helper function:
+    // Take first bytes from buffer, swap them and store those in uint16_t
+    // Swap may not be necessary
+    uint16_t uint_8BufferTouint16_t(uint8_t* buffer) {
         return (buffer[0] << 8) | buffer[1];
     }
 }