GY-63_MS5611/libraries/DMM

DMM = Digital MultiMeter.

Arduino library for a DMM class.

Description

DMM is a class that uses the Arduino analogRead to make measurements. It is based upon the UNO but will work on some other boards too.

The first version only works as a voltmeter, DC only. It is meant to be extended in the future to be a complete Digital MultiMeter class. that includes amps ohms, diode testing etc.

(this is an old 'toy' project, wrapped into a class)

Related

• https://github.com/RobTillaart/ACS712 (current measurement).

Interface

• DMM() constructor.

Configuration

• begin(uint8_t analogPin, float volts = 5.0, uint16_t maxADC = 1023) configuration.
• void setMaxVoltage(float maxVoltage)
• float getMaxVoltage()
• void setGain(float factor = 1.0) GAIN e.g. due to voltage divider. a 25V to 5V divider has a factor = 5.
• float getGain() returns the set gain.

Read

• float readVolts(uint8_t times = 1) read voltage. Times can be set to average multiple measurements.
• float readMilliVolts(uint8_t times = 1) convenience wrapper.

Calibration

• float readNoise(uint8_t times = 1) get noise level for accuracy.

Operation

Basic operation is to connect the Arduino GND to the projects GND (or -) and use the configured analog pin to measure (positive) voltage.

By adding a voltage divider one can measure larger voltages. The divider factor can be set with setGain(factor).

To elaborate.

• GND, VCC

Future

Functional

• AMPS (how -> measure voltage over a known resistor)
• OHM (how -> known divider)
• DIODE (how -> 5V or 0V)
• CAPS (how -> RC timing)

Must

• update documentation
• update examples
• add use of AREF
  • external or internal 1.1 Volt

Should

• investigate noise
• analogReference(EXTERNAL) for external voltage for build in ADC
• support external ADC e.g. ADS1115 for 16 bit resolution.

Could

• multichannel compare
• schema for
• scope functionality?

Won't