WLED/usermods/multi_relay/readme.md

Multi Relay

This usermod-v2 modification allows the connection of multiple relays, each with individual delay and on/off mode. Usermod supports PCF8574 I2C port expander to reduce GPIO use. PCF8574 supports 8 outputs and each output corresponds to a relay in WLED (relay 0 = port 0, etc). I you are using more than 8 relays with multiple PCF8574 make sure their addresses are set conscutively (e.g. 0x20 and 0x21). You can set address of first expander in settings. (NOTE: Will require Wire library and global I2C pins defined.)

HTTP API

All responses are returned in JSON format.

• Status Request: http://[device-ip]/relays
• Switch Command: http://[device-ip]/relays?switch=1,0,1,1

The number of values behind the switch parameter must correspond to the number of relays. The value 1 switches the relay on, 0 switches it off.

• Toggle Command: http://[device-ip]/relays?toggle=1,0,1,1

The number of values behind the parameter switch must correspond to the number of relays. The value 1 causes the relay to toggle, 0 leaves its state unchanged.

Examples:

1. total of 4 relays, relay 2 will be toggled: http://[device-ip]/relays?toggle=0,1,0,0
2. total of 3 relays, relay 1&3 will be switched on: http://[device-ip]/relays?switch=1,0,1

JSON API

You can toggle the relay state by sending the following JSON object to: http://[device-ip]/json

Switch relay 0 on: {"MultiRelay":{"relay":0,"on":true}}

Switch relay 3 and 4 off: {"MultiRelay":[{"relay":2,"on":false},{"relay":3,"on":false}]}

MQTT API

• wled/deviceMAC/relay/0/command on|off|toggle
• wled/deviceMAC/relay/1/command on|off|toggle

When a relay is switched, a message is published:

• wled/deviceMAC/relay/0 on|off

Usermod installation

1. Register the usermod by adding #include "../usermods/multi_relay/usermod_multi_relay.h" at the top and usermods.add(new MultiRelay()); at the bottom of usermods_list.cpp. or
2. Use #define USERMOD_MULTI_RELAY in wled.h or -D USERMOD_MULTI_RELAY in your platformio.ini

You can override the default maximum number of relays (which is 4) by defining MULTI_RELAY_MAX_RELAYS.

Example usermods_list.cpp:

#include "wled.h"
/*
 * Register your v2 usermods here!
 *   (for v1 usermods using just usermod.cpp, you can ignore this file)
 */

/*
 * Add/uncomment your usermod filename here (and once more below)
 * || || ||
 * \/ \/ \/
 */
//#include "usermod_v2_example.h"
//#include "usermod_temperature.h"
#include "../usermods/usermod_multi_relay.h"

void registerUsermods()
{
  /*
   * Add your usermod class name here
   * || || ||
   * \/ \/ \/
   */
  //usermods.add(new MyExampleUsermod());
  //usermods.add(new UsermodTemperature());
  usermods.add(new MultiRelay());

}

Configuration

Usermod can be configured via the Usermods settings page.

• enabled - enable/disable usermod
• use-PCF8574 - use PCF8574 port expander instead of GPIO pins
• first-PCF8574 - I2C address of first expander (WARNING: enter decimal value)
• broadcast- time in seconds between MQTT relay-state broadcasts
• HA-discovery- enable Home Assistant auto discovery
• pin - ESP GPIO pin the relay is connected to (can be configured at compile time -D MULTI_RELAY_PINS=xx,xx,...)
• delay-s - delay in seconds after on/off command is received
• active-high - assign high/low activation of relay (can be used to reverse relay states)
• external - if enabled, WLED does not control relay, it can only be triggered by an external command (MQTT, HTTP, JSON or button)
• button - button (from LED Settings) that controls this relay

If there is no MultiRelay section, just save current configuration and re-open Usermods settings page.

Have fun - @blazoncek

Change log

2021-04

• First implementation.

2021-11

• Added information about dynamic configuration options
• Added button support.

2023-05

• Added support for PCF8574 I2C port expander (multiple)