Relay

Control a relay with a period and duty cycle.

This module was developed to enable the use of a relay with PID control. This can be accomplished by using the PID loop to control the duty cycle of the relay.

Basic Usage

To use Relay, create an instance and set the state to running:

#define RELAY_PIN 7
#define RELAY_PERIOD 30
Relay relay(RELAY_PIN, RELAY_PERIOD);

void setup() {
   relay.setRelayMode(relayModeAutomatic);
}

Call the loop function to excercise the relay:

void loop() {
   relay.loop();
}

Function Reference:

void setRelayMode(RelayMode state);

Call setRelayMode with relayModeManual or relayModeAutomatic

• relayModeManual - Turns the relay off and disables the relay from automatic operation. Use this state for manual operation of the relay.
• relayModeAutomatic - Starts automatic operation of the relay using the period and duty cycle.

RelayMode getRelayMode(void);

Returns the state of the relay, relayModeManual or relayModeAutomatic.

void setRelayPosition(RelayPosition position);

Set the relay position:

• relayPositionOpen - The relay contacts are open.
• relayPositionClosed - The relay contacts are closed.

RelayPosition getRelayPosition(void);

Get the position of the relay, relayPositionOpen or relayPositionClosed.

void setDutyCyclePercent(double dutyCycle);

Set the duty cycle of the relay. dutyCycle must be between 0.0 and 1.0 inclusive.

double getDutyCyclePercent(void);

Get the duty cycle of the relay.

    void setPeriodInSeconds(uint16_t periodInSeconds);

Set the period of opertion of the relay in seconds.

    uint16_t getPeriodInSeconds(void);

Get the period of the operation of the relay in seconds.

Testing

To run the tests:

cd extras
make -f tdd_tests.mk

To generate test coverage reports:

./gen_cov_report.sh

An HTML test coverage report will be placed in the extras/output directory.