GY-63_MS5611/libraries/MS5611

MS5611

Arduino library for MS5611 temperature and pressure sensor.

Description

The MS5611 is a high resolution temperature and pressure sensor. The high resolution is made possible by oversampling (many times).

The device address is 0x76 or 0x77 depending on the CSB pin.

0.3.0 breaking changes

1. fixed math error so previous versions are obsolete.
2. temperature is a float expressed in degrees Celsius.
3. pressure is a float expressed in mBar.

Interface

• MS5611(uint8_t deviceAddress) constructor.
• bool begin(uint8_t sda, uint8_t scl, TwoWire *wire = &Wire) for ESP and alike, optionally set Wire interface. initializes internals,
• bool begin(TwoWire *wire = &Wire) for UNO and alike, optionally set Wire interface. Initializes internals.
• bool isConnected() checks availability of device address on the I2C bus.
• reset() resets the chip and loads constants from its ROM.
• int read(uint8_t bits) the actual reading of the sensor. Returns MS5611_READ_OK upon success.
• int read() the actual reading of the sensor. Returns MS5611_READ_OK upon success.
• void setOversampling(osr_t samplingRate) sets the amount of oversampling. See table below and test example how to use.
• osr_t getOversampling() returns amount of oversampling.
• float getTemperature() returns temperature in °C. Subsequent calls will return same value until a new read() is called.
• float getPressure() pressure is in mBar. Subsequent calls will return same value until a new read() is called.
• int getLastResult() checks last I2C communication (replace with more informative error handling?)
• uint32_t lastRead() last time when read() was called in millis() since startup.

Oversampling table

definition	value	oversampling ratio	resolution (mbar)	time (ms)	notes
OSR_ULTRA_HIGH	12	4096	0.012	8.22
OSR_HIGH	11	2048	0.018	4.1
OSR_STANDARD	10	1024	0.027	2.1
OSR_LOW	9	512	0.042	1.1
OSR_ULTRA_LOW	8	256	0.065	0.5	Default = backwards compatible

Disclaimer

The library is experimental. As I have no such sensor the quality is hard to test. So if you happen to have such a sensor, please give it a try and let me know.

Operation

See examples

Future

• get such a sensor to test
• update documentation
• create a SPI based library (same base class if possible?)
• proper error handling
• redo lower level functions?
• handle the read + math of temperature first? (need hardware to test)