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Arduino program to handle relays and control them using switches with support for double-click and long-press. Integration with home automation systems is possible through MySensors integration. Configuration is very simple - one line for a single relay and one line for single switch Every switch support debouncing, multiple types of switches and additional actions like double-click and long-press - everything in a single line of configuration. Relays can be configured as LOW/HIGH level trigger, startup state ON or OFF and impulse type. One relay can have one or more switches, or not at all if you want to control it only by home automation system.

Copy file "config.h.sample" into "config.h". There is sample configuration you need to examine and customize for your own needs.

You need PlatformIO - it is free and you can get it here https://platformio.org/platformio-ide. Arduino IDE is not supported. By default sketch is built for Arduino Mega 2560. Build options can be customized in platformio.ini - more information in separate sections. Remote upload (ie. Arduino connected to Raspberry PI) is supported. For more information read https://docs.platformio.org/en/latest/core/userguide/remote/cmd_agent.html.

const RelayConfigDef gRelayConfig[] PROGMEM = {
  {sensor id, relay pin, relay options, relay dependOn, relay description}
};

Params description:

• sensor id - sensor ID reported on MySensor Gateway (ie. Domoticz/Home Assistant), must be unique
• relay pin - pin connected to the relay. Expander is supported (see details in separate section), must be unique
• relay options - combined with '|' operator:
  • RELAY_TRIGGER_LOW or RELAY_TRIGGER_HIGH - required, trigger level
  • RELAY_STARTUP_ON or RELAY_STARTUP_OFF - optional, startup state
  • RELAY_IMPULSE - optional, relay is turned on only for short period of time (defined in constant RELAY_IMPULSE_INTERVAL, 250ms by default), ignored for DING_DONG and REED_SWITCH buttons
• relay dependOn - ID of relay that needs to be turned on before this one
• relay description - reported on MySensor Gateway, can help identify device on initial configuration in Home Automation System, max. 30 chars, can be empty ("")

const ButtonConfigDef gButtonConfig[] PROGMEM = {
  {button pin, button type, click relay id, long-click relay id, double-click relay id, button description}
};

Params description:

• button pin - pin connected to the button. Expander is supported (see details in separate section) but not recomended for switches
• button type:
  • MONO_STABLE - for impulse switches, mainly mechanical, which are shorted to the GND when pushed
  • BI_STABLE - state change from LOW to HIGH and HIGH to LOW, used with mechanical and touch buttons
  • DING_DONG - doorbell button, relay is triggered only when button is pushed
  • REED_SWITCH - door/window sensor, oposite to DING_DONG - state OFF when door/window is closed, ON when opened. All relays with at least one REED_SWITCH are reported throught MySensors as S_DOOR sensor.
• click relay id - sensor id used in relay configuration
• long-click relay id - sensor id used in relay configuration, -1 when not used, ignored for DING_DONG/REED_SWITCH
• double-click relay id - sensor id used in relay configuration, -1 when not used, ignored for DING_DONG/REED_SWITCH
• button description - debug only information, max. 30 chars, can be empty ("")

const RelayConfigDef gRelayConfig[] PROGMEM = {
  {26, 31, RELAY_TRIGGER_HIGH, "Garage Door"},
  ...
};
const ButtonConfigDef gButtonConfig[] PROGMEM = {
  {43, REED_SWITCH, 26, -1, -1, "Garage Door reed switch"},
  ...
};

In this case relay 26 is always reported throught as S_DOOR sensor, i.e. in Home Assistant this relay can be found in entities as binary_sensor.multi_relay_0_26.

The "dependOn" option in relays configuration is intended for turning ON and OFF power supplies, not to create scenes. For example, you have 12V power supply and two 12V LED lights:

...
  {11, A1, RELAY_TRIGGER_LOW, 13, "LED Strip"},
  {12, A2, RELAY_TRIGGER_LOW, 13, "Stairs light"},
  {13, A3, RELAY_TRIGGER_LOW, -1, "Power supply 12V"},
...

When you turn on LED Strip and/or Stairs light, then Power supply 12V will be automatically turned on. Power supply 12V will be automatically turned off, when all parent devices will be turned off.

Optional configuration only if you want to customize the script.

MONO_STABLE switches can trigger ralay when switch is pressed (LOW) or when switch is released (HIGH):

const uint8_t MONO_STABLE_TRIGGER = LOW;

Time interval for RELAY_IMPULSE type relay, ignored when button type is DING_DONG or REED_SWITCH:

const unsigned long RELAY_IMPULSE_INTERVAL = 250;

Debounce interval in milliseconds:

const unsigned long BUTTON_DEBOUNCE_INTERVAL = 50;

Double-click interval in milliseconds:

const unsigned long BUTTON_DOUBLE_CLICK_INTERVAL = 350;

Long-press interval in milliseconds:

const unsigned long BUTTON_LONG_PRESS_INTERVAL = 800;

Sketch description reported via MySensors to Home Automation System:

const char MULTI_RELAY_DESCRIPTION[] PROGMEM = "Multi Relay";

In a platformio.ini file in section [common_env_data] you can uncomment (remove ";" at the beginning) some build_flags:

• DEBUG_STATS=1000 - time statistics can be printed on serial, when they are triggered via appropriate MySensors command - read more in MySensors commands sections
• DEBUG_COMMUNICATION - show some debug information about received MySensors commands on serial
• DEBUG_ACTION - detailed information about button actions on serial
• DEBUG_STARTUP - detaled information about configuration parameters. Usefull when you want report some problems with sketch.

Only one expander library at a time is supported.

To use expander PCF8574 you have to install library:

• download https://github.com/skywodd/pcf8574_arduino_library as zip archive
• extract directory PCF8574 into lib/PCF8574 Basic information about expander and library you can find here - https://youtu.be/JNmVREucfyc (PL, library in description)

And in a platformio.ini file in section [common_env_data] uncomment EXPANDER_PCF8574 in build_flags.

https://github.com/adafruit/Adafruit-MCP23017-Arduino-Library

In a platformio.ini file in section [common_env_data] uncomment expander library in lib_deps_builtin:

adafruit/Adafruit MCP23017 Arduino Library @ ^1.2.0

and EXPANDER_MCP23017 in build_flags.

Configure expander id in config.h file:

const uint8_t gExpanderAddresses[] = {0x20}; //PCF8574

or MCP23017:

const uint8_t gExpanderAddresses[] = {0}; //MCP23017

For multiple expanders use different id's:

const uint8_t gExpanderAddresses[] = {0, 1, 2}; //MCP23017

From now you can use expander pins in configuration of realays and buttons. To recognize expander pin, numbers start from 0x0100 and have special meaning:

• first byte - expander number (starts from 1)
• second byte - pin number In example - "0x0100" means pin 0 on first expander

To simplify using expanders, there is "E(a,b)" macro:

• a - expander number (starts from 0)
• b - pin on expander [0-f]

E(0,0) - first pin on first expander

const RelayConfigDef gRelayConfig[] PROGMEM = {
  {1, E(0,3), RELAY_TRIGGER_LOW, "RELAY 1"}
};

If you have problems with unstable relay or button states after startup, uncomment IGNORE_BUTTONS_START_MS=2000 in your platformio.ini.

Show debug stats

0;255;1;0;24;1

Show all relays state

0;255;1;0;24;2

Show all buttons state

0;255;1;0;24;3

Dump EEPROM

0;255;1;0;24;4

Clean EEPROM & reset

0;255;1;0;24;5

Reset

0;255;1;0;24;6