mirror of
https://github.com/RobTillaart/Arduino.git
synced 2024-09-20 00:55:58 -04:00
95 lines
2.7 KiB
Markdown
95 lines
2.7 KiB
Markdown
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[](https://github.com/marketplace/actions/arduino_ci)
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[](https://github.com/RobTillaart/DMM/actions/workflows/arduino-lint.yml)
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[](https://github.com/RobTillaart/DMM/actions/workflows/jsoncheck.yml)
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[](https://github.com/RobTillaart/DMM/blob/master/LICENSE)
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[](https://github.com/RobTillaart/DMM/releases)
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# DMM = Digital MultiMeter.
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Arduino library for a DMM class.
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## Description
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DMM is a class that uses the Arduino analogRead to make measurements.
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It is based upon the UNO but will work on some other boards too.
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The first version only works as a voltmeter, DC only.
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It is meant to be extended in the future to be a complete Digital MultiMeter class.
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that includes amps ohms, diode testing etc.
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(this is an old 'toy' project, wrapped into a class)
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#### Related
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- https://github.com/RobTillaart/ACS712 (current measurement).
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## Interface
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- **DMM()** constructor.
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#### Configuration
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- **begin(uint8_t analogPin, float volts = 5.0, uint16_t maxADC = 1023)** configuration.
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- **void setMaxVoltage(float maxVoltage)**
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- **float getMaxVoltage()**
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- **void setGain(float factor = 1.0)** GAIN e.g. due to voltage divider.
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a 25V to 5V divider has a factor = 5.
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- **float getGain()** returns the set gain.
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#### Read
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- **float readVolts(uint8_t times = 1)** read voltage.
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Times can be set to average multiple measurements.
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- **float readMilliVolts(uint8_t times = 1)** convenience wrapper.
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#### Calibration
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- **float readNoise(uint8_t times = 1)** get noise level for accuracy.
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## Operation
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Basic operation is to connect the Arduino GND to the projects GND (or -)
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and use the configured analog pin to measure (positive) voltage.
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By adding a voltage divider one can measure larger voltages.
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The divider factor can be set with **setGain(factor)**.
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To elaborate.
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- GND, VCC
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## Future
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#### Functional
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- AMPS (how -> measure voltage over a known resistor)
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- OHM (how -> known divider)
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- DIODE (how -> 5V or 0V)
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- CAPS (how -> RC timing)
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#### Must
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- update documentation
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- update examples
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- add use of AREF
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- external or internal 1.1 Volt
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#### Should
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- investigate noise
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- analogReference(EXTERNAL) for external voltage for build in ADC
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- support external ADC e.g. ADS1115 for 16 bit resolution.
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#### Could
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- multichannel compare
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- schema for
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- scope functionality?
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#### Won't
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