Trinket Tipping Bucket module

Introduction

This module is for use with a simple external I2C tipping bucket counter based on an Adafriut Trinket. This is NOT for direct counting of tips using an interrupt on the main processor. The construction and programming of the tipping bucket counter is documented on GitHub. It is assumed that the processor of the tip counter takes care of its own power management.

Sensor Datasheet

• Adafriut Trinket
• I2C Tipping Bucket Library

Build flags

• -D MS_RAIN_SOFTWAREWIRE

  • switches from using hardware I2C to software I2C

Sensor Constructors

Example Code

The Arduino-based I2C tipping bucket rain counter is used in the menu a la carte example.

#include <sensors/RainCounterI2C.h>

const uint8_t RainCounterI2CAddress = 0x08;
// I2C Address for EnviroDIY external tip counter; 0x08 by default
const float depthPerTipEvent = 0.2;  // rain depth in mm per tip event

// Create a Rain Counter sensor object
#ifdef MS_RAIN_SOFTWAREWIRE
RainCounterI2C tbi2c(&softI2C, RainCounterI2CAddress, depthPerTipEvent);
// RainCounterI2C tbi2c(softwareSDA, softwareSCL, RainCounterI2CAddress,
//                      depthPerTipEvent);
#else
RainCounterI2C  tbi2c(RainCounterI2CAddress, depthPerTipEvent);
#endif

// Create number of tips and rain depth variable pointers for the tipping bucket
Variable* tbi2cTips =
    new RainCounterI2C_Tips(&tbi2c, "12345678-abcd-1234-ef00-1234567890ab");
Variable* tbi2cDepth =
    new RainCounterI2C_Depth(&tbi2c, "12345678-abcd-1234-ef00-1234567890ab");

Classes

class RainCounterI2C

The Sensor sub-class for the Arduino-based external tipping bucket counter.

class RainCounterI2C_Tips

The Variable sub-class used for the total tip count output from an Adafruit Trinket based I2C tipping bucket counter.

class RainCounterI2C_Depth

The Variable sub-class used for the depth of rain output from an Adafruit Trinket based I2C tipping bucket counter.

Defines

#define BUCKET_NUM_VARIABLES = 2

Sensor::_numReturnedValues; the tipping bucket counter can report 2 values.

#define BUCKET_INC_CALC_VARIABLES = 1

Sensor::_incCalcValues; we calculate rain depth from the number of tips, assuming either English or metric calibration.

Sensor Timing

The sensor timing for a Trinket-based tipping bucket counter

• Readings transferred from the tipping bucket to the logger are from past tips, so there is no need to wait for stability or measuring.

#define BUCKET_WARM_UP_TIME_MS = 0

Sensor::_warmUpTime_ms; the tipping bucket counter warms up in 0ms.

#define BUCKET_STABILIZATION_TIME_MS = 0

Sensor::_stabilizationTime_ms; the tipping bucket counter is stable after 0ms.

#define BUCKET_MEASUREMENT_TIME_MS = 0

Sensor::_measurementTime_ms; the tipping bucket counter takes 0ms to complete a measurement.

Rain Depth

The rain depth variable from a Trinket-based tipping bucket counter

• Range and accuracy depend on the tipping bucket used

#define BUCKET_RAIN_RESOLUTION = 2

Decimals places in string representation; rain depth should have 2.

Resolution is typically either 0.01" or 0.2mm of rainfall, depending on if bucket is calibrated to English or metric units.

#define BUCKET_RAIN_VAR_NUM = 0

Sensor variable number; rain depth is stored in sensorValues[0].

#define BUCKET_RAIN_VAR_NAME = "precipitation"

Variable name in ODM2 controlled vocabulary; "precipitation".

#define BUCKET_RAIN_UNIT_NAME = "millimeter"

Variable unit name in ODM2 controlled vocabulary; "millimeter".

#define BUCKET_RAIN_DEFAULT_CODE = "RainCounterI2CVol"

Default variable short code; "RainCounterI2CVol".

Tip Count

Defines for tip count variable from a Trinket-based tipping bucket counter

• Range and accuracy depend on the tipping bucket used.

#define BUCKET_TIPS_RESOLUTION = 0

Decimals places in string representation; the number of tips should have 0 - resolution is 1 tip.

#define BUCKET_TIPS_VAR_NUM = 1

Sensor variable number; the number of tips is stored in sensorValues[1].

#define BUCKET_TIPS_VAR_NAME = "precipitation"

Variable name in ODM2 controlled vocabulary; "precipitation".

#define BUCKET_TIPS_UNIT_NAME = "event"

Variable unit name in ODM2 controlled vocabulary; "event".

#define BUCKET_TIPS_DEFAULT_CODE = "RainCounterI2CTips"

Default variable short code; "RainCounterI2CTips".