i2c: add bmp280 driver, then encapsulate it with bme280 and add Humidity

Signed-off-by: deadprogram <ron@hybridgroup.com>

drivers/i2c/bme280_driver.go

@@ -3,29 +3,11 @@ package i2c
 import (
 	"bytes"
 	"encoding/binary"
-
-	"gobot.io/x/gobot"
 )
 
 const bme280RegisterHumidityMSB = 0xFD
 const bme280RegisterCalibDigH1 = 0xa1
 const bme280RegisterCalibDigH2LSB = 0xe1
-const bmp280RegisterCalib00 = 0x88
-
-type bmp280CalibrationCoefficients struct {
-	t1 uint16
-	t2 int16
-	t3 int16
-	p1 uint16
-	p2 int16
-	p3 int16
-	p4 int16
-	p5 int16
-	p6 int16
-	p7 int16
-	p8 int16
-	p9 int16
-}
 
 type bmeHumidityCalibrationCoefficients struct {
 	h1 uint8
@@ -38,13 +20,8 @@ type bmeHumidityCalibrationCoefficients struct {
 
 // BME280Driver is a driver for the BME280 temperature/humidity sensor
 type BME280Driver struct {
-	name       string
+	*BMP280Driver
-	connector  Connector
+	hc *bmeHumidityCalibrationCoefficients
-	connection Connection
-	Config
-
-	tpc *bmp280CalibrationCoefficients
-	hc  *bmeHumidityCalibrationCoefficients
 }
 
 // NewBME280Driver creates a new driver with specified i2c interface.
@@ -57,11 +34,8 @@ type BME280Driver struct {
 //
 func NewBME280Driver(c Connector, options ...func(Config)) *BME280Driver {
 	b := &BME280Driver{
-		name:      gobot.DefaultName("BME280"),
+		BMP280Driver: NewBMP280Driver(c),
-		connector: c,
+		hc:           &bmeHumidityCalibrationCoefficients{},
-		Config:    NewConfig(),
-		tpc:       &bmp280CalibrationCoefficients{},
-		hc:        &bmeHumidityCalibrationCoefficients{},
 	}
 
 	for _, option := range options {
@@ -72,21 +46,6 @@ func NewBME280Driver(c Connector, options ...func(Config)) *BME280Driver {
 	return b
 }
 
-// Name returns the name of the device.
-func (d *BME280Driver) Name() string {
-	return d.name
-}
-
-// SetName sets the name of the device.
-func (d *BME280Driver) SetName(n string) {
-	d.name = n
-}
-
-// Connection returns the connection of the device.
-func (d *BME280Driver) Connection() gobot.Connection {
-	return d.connector.(gobot.Connection)
-}
-
 // Start initializes the BME280 and loads the calibration coefficients.
 func (d *BME280Driver) Start() (err error) {
 	bus := d.GetBusOrDefault(d.connector.GetDefaultBus())
@@ -96,68 +55,23 @@ func (d *BME280Driver) Start() (err error) {
 		return err
 	}
 
-	// TODO: set sleep mode here...
-
 	if err := d.initialization(); err != nil {
 		return err
 	}
+
 	if err := d.initHumidity(); err != nil {
 		return err
 	}
 
-	// TODO: set usage mode here...
-
-	// TODO: set default sea level here
-
 	return nil
 }
 
-// Halt halts the device.
-func (d *BME280Driver) Halt() (err error) {
-	return nil
-}
-
-// Temperature returns the current temperature, in celsius degrees.
-func (d *BME280Driver) Temperature() (temp float32, err error) {
-	// TODO: implement this
-	return 0, nil
-}
-
-// Pressure returns the current barometric pressure, in Pa
-func (d *BME280Driver) Pressure() (press float32, err error) {
-	// TODO: implement this
-	return 0, nil
-}
-
 // Humidity returns the current humidity in percentage of relative humidity
 func (d *BME280Driver) Humidity() (humidity float32, err error) {
 	// TODO: implement this
 	return 0, nil
 }
 
-// initialization reads the calibration coefficients.
-func (d *BME280Driver) initialization() (err error) {
-	var coefficients []byte
-	if coefficients, err = d.read(bmp280RegisterCalib00, 26); err != nil {
-		return err
-	}
-	buf := bytes.NewBuffer(coefficients)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.t1)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.t2)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.t3)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p1)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p2)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p3)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p4)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p5)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p6)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p7)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p8)
-	binary.Read(buf, binary.LittleEndian, &d.tpc.p9)
-
-	return nil
-}
-
 // read the humidity calibration coefficients.
 func (d *BME280Driver) initHumidity() (err error) {
 	var coefficients []byte
@@ -190,21 +104,6 @@ func (d *BME280Driver) initHumidity() (err error) {
 	return nil
 }
 
-// TODO: implement
-func (d *BME280Driver) rawTempPress() (temp int16, press int16, err error) {
-	return 0, 0, nil
-}
-
-// TODO: implement
-func (d *BME280Driver) calculateTemp(rawTemp int16) float32 {
-	return 0
-}
-
-// TODO: implement
-func (d *BME280Driver) calculatePress(rawPress int16) float32 {
-	return 0
-}
-
 func (d *BME280Driver) rawHumidity() (int16, error) {
 	ret, err := d.read(bme280RegisterHumidityMSB, 2)
 	if err != nil {
@@ -247,15 +146,3 @@ func (d *BME280Driver) calculateHumidity(rawH int16) float32 {
 
 	return h * y
 }
-
-func (d *BME280Driver) read(address byte, n int) ([]byte, error) {
-	if _, err := d.connection.Write([]byte{address}); err != nil {
-		return nil, err
-	}
-	buf := make([]byte, n)
-	bytesRead, err := d.connection.Read(buf)
-	if bytesRead != n || err != nil {
-		return nil, err
-	}
-	return buf, nil
-}

drivers/i2c/bmp280_driver.go

@@ -0,0 +1,168 @@
+package i2c
+
+import (
+	"bytes"
+	"encoding/binary"
+
+	"gobot.io/x/gobot"
+)
+
+const bmp280RegisterCalib00 = 0x88
+
+type bmp280CalibrationCoefficients struct {
+	t1 uint16
+	t2 int16
+	t3 int16
+	p1 uint16
+	p2 int16
+	p3 int16
+	p4 int16
+	p5 int16
+	p6 int16
+	p7 int16
+	p8 int16
+	p9 int16
+}
+
+// BMP280Driver is a driver for the BMP280 temperature/pressure sensor
+type BMP280Driver struct {
+	name       string
+	connector  Connector
+	connection Connection
+	Config
+
+	tpc *bmp280CalibrationCoefficients
+}
+
+// NewBMP280Driver creates a new driver with specified i2c interface.
+// Params:
+//		conn Connector - the Adaptor to use with this Driver
+//
+// Optional params:
+//		i2c.WithBus(int):	bus to use with this driver
+//		i2c.WithAddress(int):	address to use with this driver
+//
+func NewBMP280Driver(c Connector, options ...func(Config)) *BMP280Driver {
+	b := &BMP280Driver{
+		name:      gobot.DefaultName("BMP280"),
+		connector: c,
+		Config:    NewConfig(),
+		tpc:       &bmp280CalibrationCoefficients{},
+	}
+
+	for _, option := range options {
+		option(b)
+	}
+
+	// TODO: expose commands to API
+	return b
+}
+
+// Name returns the name of the device.
+func (d *BMP280Driver) Name() string {
+	return d.name
+}
+
+// SetName sets the name of the device.
+func (d *BMP280Driver) SetName(n string) {
+	d.name = n
+}
+
+// Connection returns the connection of the device.
+func (d *BMP280Driver) Connection() gobot.Connection {
+	return d.connector.(gobot.Connection)
+}
+
+// Start initializes the BMP280 and loads the calibration coefficients.
+func (d *BMP280Driver) Start() (err error) {
+	bus := d.GetBusOrDefault(d.connector.GetDefaultBus())
+	address := d.GetAddressOrDefault(bmp180Address)
+
+	if d.connection, err = d.connector.GetConnection(address, bus); err != nil {
+		return err
+	}
+
+	// TODO: set sleep mode here...
+
+	if err := d.initialization(); err != nil {
+		return err
+	}
+
+	// TODO: set usage mode here...
+
+	// TODO: set default sea level here
+
+	return nil
+}
+
+// Halt halts the device.
+func (d *BMP280Driver) Halt() (err error) {
+	return nil
+}
+
+// Temperature returns the current temperature, in celsius degrees.
+func (d *BMP280Driver) Temperature() (temp float32, err error) {
+	// TODO: implement this
+	return 0, nil
+}
+
+// Pressure returns the current barometric pressure, in Pa
+func (d *BMP280Driver) Pressure() (press float32, err error) {
+	// TODO: implement this
+	return 0, nil
+}
+
+// initialization reads the calibration coefficients.
+func (d *BMP280Driver) initialization() (err error) {
+	// TODO: set sleep mode here...
+
+	var coefficients []byte
+	if coefficients, err = d.read(bmp280RegisterCalib00, 26); err != nil {
+		return err
+	}
+	buf := bytes.NewBuffer(coefficients)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.t1)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.t2)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.t3)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p1)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p2)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p3)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p4)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p5)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p6)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p7)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p8)
+	binary.Read(buf, binary.LittleEndian, &d.tpc.p9)
+
+	// TODO: set usage mode here...
+	// TODO: set default sea level here
+
+	return nil
+}
+
+// TODO: implement
+func (d *BMP280Driver) rawTempPress() (temp int16, press int16, err error) {
+	return 0, 0, nil
+}
+
+// TODO: implement
+func (d *BMP280Driver) calculateTemp(rawTemp int16) float32 {
+	return 0
+}
+
+// TODO: implement
+func (d *BMP280Driver) calculatePress(rawPress int16) float32 {
+	return 0
+}
+
+func (d *BMP280Driver) read(address byte, n int) ([]byte, error) {
+	if _, err := d.connection.Write([]byte{address}); err != nil {
+		return nil, err
+	}
+	buf := make([]byte, n)
+	bytesRead, err := d.connection.Read(buf)
+	if bytesRead != n || err != nil {
+		return nil, err
+	}
+	return buf, nil
+}

drivers/i2c/bmp280_driver_test.go

@@ -0,0 +1,64 @@
+package i2c
+
+import (
+	"testing"
+
+	"gobot.io/x/gobot"
+	"gobot.io/x/gobot/gobottest"
+)
+
+var _ gobot.Driver = (*BMP280Driver)(nil)
+
+// --------- HELPERS
+func initTestBMP280Driver() (driver *BMP280Driver) {
+	driver, _ = initTestBMP280DriverWithStubbedAdaptor()
+	return
+}
+
+func initTestBMP280DriverWithStubbedAdaptor() (*BMP280Driver, *i2cTestAdaptor) {
+	adaptor := newI2cTestAdaptor()
+	return NewBMP280Driver(adaptor), adaptor
+}
+
+// --------- TESTS
+
+func TestNewBMP280Driver(t *testing.T) {
+	// Does it return a pointer to an instance of BME280Driver?
+	var bmp280 interface{} = NewBMP280Driver(newI2cTestAdaptor())
+	_, ok := bmp280.(*BMP280Driver)
+	if !ok {
+		t.Errorf("NewBMP280Driver() should have returned a *BMP280Driver")
+	}
+}
+
+func TestBMP280Driver(t *testing.T) {
+	bmp280 := initTestBMP280Driver()
+	gobottest.Refute(t, bmp280.Connection(), nil)
+}
+
+func TestBMP280DriverStart(t *testing.T) {
+	bmp280, _ := initTestBMP280DriverWithStubbedAdaptor()
+	gobottest.Assert(t, bmp280.Start(), nil)
+}
+
+func TestBMP280DriverHalt(t *testing.T) {
+	bmp280 := initTestBMP280Driver()
+
+	gobottest.Assert(t, bmp280.Halt(), nil)
+}
+
+// TODO: implement test
+func TestBMP280DriverMeasurements(t *testing.T) {
+
+}
+
+func TestBMP280DriverSetName(t *testing.T) {
+	b := initTestBMP280Driver()
+	b.SetName("TESTME")
+	gobottest.Assert(t, b.Name(), "TESTME")
+}
+
+func TestBMP280DriverOptions(t *testing.T) {
+	b := NewBMP280Driver(newI2cTestAdaptor(), WithBus(2))
+	gobottest.Assert(t, b.GetBusOrDefault(1), 2)
+}