Initial commit.

include/baro_channel.h

@@ -0,0 +1,100 @@
+#pragma once
+
+#include <Arduino.h>
+#include <math.h>
+
+#include "config.h"
+#include "ms5611_crc.h"
+
+//
+//  One validated MS5611 measurement channel.
+//
+//  The class owns everything that is identical for both sensors - reset and
+//  PROM/CRC handshake, per-poll validation, error accounting and the 1 second
+//  error LED pulse. Only the five driver calls at the bottom are virtual, and
+//  they are implemented once for the I2C part and once for the SPI part.
+//
+
+enum class BaroStatus : uint8_t
+{
+  NotInitialised = 0,
+  Ok,
+  InitFailed,     //  reset/handshake did not complete
+  PromCrcError,   //  factory calibration failed its CRC-4 or is implausible
+  ReadError,      //  the driver reported a bus/ADC failure
+  OutOfRange,     //  values outside the MS5611 operating envelope
+  Stale,          //  sensor answers but has stopped producing new samples
+};
+
+//  Short, log-friendly name for a status - never returns NULL.
+const char *baroStatusName(BaroStatus status);
+
+
+class BaroChannel
+{
+public:
+  BaroChannel(const char *name, uint8_t ledPin)
+    : _name(name), _ledPin(ledPin) {}
+
+  //  Configures the LED pin and makes the first initialisation attempt.
+  void begin(uint32_t now);
+
+  //  One acquisition cycle: read, validate, update status and LED.
+  //  Blocks for roughly 2x the ADC conversion time of the configured OSR.
+  void poll(uint32_t now);
+
+  //  Releases the error LED once its hold time has elapsed. Cheap, call often.
+  void updateLed(uint32_t now);
+
+  const char *name() const        { return _name; }
+  BaroStatus  status() const      { return _status; }
+  bool        isOk() const        { return _status == BaroStatus::Ok; }
+  float       pressure() const    { return _pressure; }     //  mbar
+  float       temperature() const { return _temperature; }  //  degrees C
+  uint32_t    errorCount() const  { return _errorCount; }
+
+protected:
+  //  Not deleted through this type - keeps the vtable free of a destructor
+  //  slot and avoids dragging in operator delete.
+  ~BaroChannel() = default;
+
+  //  Reset the part and apply the configured oversampling.
+  virtual bool  driverBegin() = 0;
+  //  Fill prom[0..7] with the factory calibration words.
+  virtual void  driverReadProm(uint16_t *prom) = 0;
+  //  True when the driver reported MS5611_READ_OK.
+  virtual bool  driverRead() = 0;
+  virtual float driverPressure() = 0;
+  virtual float driverTemperature() = 0;
+
+private:
+  bool tryInit(uint32_t now);
+  void fail(BaroStatus status, uint32_t now);
+
+  const char *_name;
+  uint8_t     _ledPin;
+
+  BaroStatus  _status          = BaroStatus::NotInitialised;
+  bool        _initialised     = false;
+  uint32_t    _lastInitAttempt = 0;
+
+  float       _pressure        = NAN;
+  float       _temperature     = NAN;
+
+  uint8_t     _repeatCount     = 0;
+  uint8_t     _errorStreak     = 0;
+  uint32_t    _errorCount      = 0;
+
+  bool        _ledOn           = false;
+  uint32_t    _ledOffAt        = 0;
+};
+
+
+//
+//  The two concrete channels are built in their own translation units on
+//  purpose: MS5611.h and MS5611_SPI.h each define `enum osr_t` and their own
+//  MS5611_READ_OK, so including both in one file does not compile. These
+//  accessors hand out the instances without leaking either driver header.
+//
+BaroChannel &baroI2cChannel();
+BaroChannel &baroSpiChannel();