# DAFFY-4 - Four relays outputs and four clean contacts input DIN rail I2C board 

<abstract>
This article ilustrates what is and how to use the Daffy-4 board
</abstract>

<img style="max-width:640px; width:100%;" src="./daffy-4.jpg">

## Features

* 4 relay output 
	* Normaly open and normaly closed screw terminals
	* Panason ALQ112 
	* 10A 250VAC 
	* Surge 8,000 V, High breakdown voltage 4,000 V (Between contact and coil)
	* RC snubber circuitry on NO and NC contacts to suppress voltage transients
* 4 clean contact input
	* Electrostatic transient protections on each input
* I2C buffer 
	* Bus speed up to 400-kHz 
	* Input and output screw separate screw terminal
	* On-board repeater buffer between input and output terminals 
* Pitch 5mm screw terminals for all signals
* Double Acme FPC six connector for WiFi controller and Acme Sensors boards  
* Power in 12VDC
* DIN rail case (6 module)

## I2C Addressing

Daffy-4 can use up to 8 different I2C addres setting the SW1 dip switch. The factory default 
address is 0x38 (all SELx switches in OFF position)


| SEL2 (A2)  | SEL1 (A1) | SEL0 (A0) | Hex Address | Dec Address | 
|------------|-----------|-----------|-------------|-------------|
| ON (0)     | ON (0)    | ON (0)    | 0x38        | 56          |
| ON (0)     | ON (0)    | OFF (1)   | 0x39        | 57          |
| ON (0)     | OFF (1)   | ON (0)    | 0x3A        | 58          |
| ON (0)     | OFF (1)   | OFF (1)   | 0x3B        | 59          |
| OFF (1)    | ON (0)    | ON (0)    | 0x3C        | 60          |
| OFF (1)    | ON (0)    | OFF (1)   | 0x3D        | 61          |
| OFF (1)    | OFF (1)   | ON (0)    | 0x3E        | 62          |
| OFF (1)    | OFF (1)   | OFF (1)   | 0x3F        | 63          |

Each board has a I2C bi-directional buffer that regenerates the bus voltage levels provided to the next board

### Wire and search the DAFFY-4 board on Acme-Sensor 2 port

Set the Daffy-4 dip switches in this way:

| SEL 0 | SEL 1 | SEL 2 | Addess Hex | Address Dec |
|-------|-------|-------|------------|-------------|
| ON    | ON    | ON    | 0x38       | 56          |

Wire the Daffy-4 board to the Acme sensor port 2

Scan the I2C bus to check the board presence:

	sudo i2cdetect -y 1
	
	     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
	00:                         -- -- -- -- -- -- -- -- 
	10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
	20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
	30: -- -- -- -- -- -- -- -- 38 -- -- -- -- -- -- -- 
	40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
	50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
	60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
	70: -- -- -- -- -- -- -- --  

### Python examples

Install python3-smbus package by typing:

	sudo apt update
	sudo apt install python3-smbus

Save this Python3 code inside a file called daffy.py:

	import smbus
	import time
	
	DEVICE_BUS = 1 # /dev/i2c-1
	
	# Board list
	BOARD_ADDR=[56];
	
	# Output value to send on each board
	RELAY_OUT=[0x10,0x20,0x40,0x80,0x00];
	
	Reg_InputPort =          0x00 # default 0x00
	Reg_OutputPort =         0x01 # default 0xFF
	Reg_PolarityInversion =  0x02 # default 0x00; polarity invert
	Reg_Configuration =      0x03 # default 0xFF, 1 = input; 0 = output;
	
	bus = smbus.SMBus(DEVICE_BUS)
	
	for addr in BOARD_ADDR:
		print("Send configuration to board: " + "0x{:02x}".format(addr))
		bus.write_byte_data(addr, Reg_Configuration,0x0F)
	
	while True:
		for addr in BOARD_ADDR:
			for relay_bitmap in RELAY_OUT:
				print("Send " + "0x{:02x}".format(relay_bitmap) + " to board " + hex(addr))
				bus.write_byte_data(addr, Reg_OutputPort,relay_bitmap)
				time.sleep(0.2);

Turn on teh Acme sensor port 2

* Power line ON (PIOBU5)  <code>sudo gpioset gpiochip1 5=1</code>
* Power line OFF (PIOBU5) <code>sudo gpioset gpiochip1 5=0</code>

Then type:

	sudo python3 daffy.py
	
If you have two or more boards add their address on this line:

	BOARD_ADDR=[56,57,58];

and set the switch on each board:

| Board # | SEL 0 | SEL 1 | SEL 2 | Addess Hex | Address Dec |
|---------|-------|-------|-------|------------|-------------|
| 1       | ON    | ON    | ON    | 0x38       | 56          |
| 2       | OFF   | ON    | ON    | 0x39       | 57          |
| 3       | ON    | OFF   | ON    | 0x3A       | 58          |
| ...     | ...   | ...   | ...   | ...        | ...         | 


## Manage the Daffy-4 board using an ESP8266-12F

	#include <WiFiClient.h>
	#include <ESP8266WiFi.h>
	#include <MQTT.h>
	#include <PubSubClient.h>
	
	#include <Wire.h>
	
	//----SERIAL CONFIG ----
	#define SERIAL_SPEED        115200
	
	//----WIFI CONFIG ----
	#define WIFI_SSID           "acmetest"
	#define WIFI_PASSWD         "acmetest"
	#define MAX_WIFI_INIT_RETRY 10
	#define WIFI_RETRY_DELAY    500
	
	//----MQTT CONFIG ----
	#define MQTT_SERVER         "192.168.1.95"
	#define MQTT_UNAME          ""
	#define MQTT_PASSW          ""
	#define MQTT_BROKER_PORT    1883          
	#define MQTT_CLIENT_ID      "1234"
	
	WiFiClient wifi_client;
	PubSubClient mqtt_client(wifi_client, MQTT_SERVER, MQTT_BROKER_PORT);
	
	//unsigned long delayTime;
	
	//Wifi Initialization function
	int WiFi_init()
	{
	  const char* wifi_ssid   = WIFI_SSID;
	  const char* wifi_passwd = WIFI_PASSWD;
	
	  int retries = 0;
	
	  Serial.println("Connecting to WiFi AP..........");
	
	  WiFi.mode(WIFI_STA); //set wifi station mode
	
	  WiFi.begin(wifi_ssid, wifi_passwd); //start connecting to WiFi AP
	
	  //check the status of WiFi connection to be WL_CONNECTED
	  while ((WiFi.status() != WL_CONNECTED) && (retries < MAX_WIFI_INIT_RETRY)) {
	    retries++;
	    delay(WIFI_RETRY_DELAY);
	    Serial.println("#");
	  }
	  Serial.println(String(WiFi.localIP()[0]) + "." + String(WiFi.localIP()[1]) + "." + String(WiFi.localIP()[2]) + "." + String(WiFi.localIP()[3]));
	
	  return WiFi.status(); //return the WiFi connection status
	}
	
	void mqtt_callback(const MQTT::Publish& pub)
	{
	  Serial.println("MQTT receiving a message:");
	  Serial.println(pub.payload_string());
	
	  if (pub.payload_string()=="ON") {
	    Wire.beginTransmission(0x38);
	    Wire.write(0x03);
	    Wire.write(0x0F);
	    Wire.endTransmission();    // stop transmitting
	
	    Wire.beginTransmission(0x38);
	    Wire.write(0x01);
	    Wire.write(0xF0);
	    Wire.endTransmission();    // stop transmitting
	  } else {
	    Wire.beginTransmission(0x38);
	    Wire.write(0x03);
	    Wire.write(0x0F);
	    Wire.endTransmission();    // stop transmitting
	
	    Wire.beginTransmission(0x38);
	    Wire.write(0x01);
	    Wire.write(0x00);
	    Wire.endTransmission();    // stop transmitting
	  }
	  
	}
	
	void setup() {
	  Serial.begin(SERIAL_SPEED);
	  Wire.begin();
	  delay(100);
	
	  Serial.println("Program Start");
	
	  Wire.begin();
	  Wire.write(0x03);
	  Wire.write(0x0F);
	
	  // WiFi
	  while(true) {
	    Serial.println("WiFi try");
	    if (WiFi_init()==WL_CONNECTED) {
	      Serial.println("WiFi success");
	      break;
	    }
	
	    Serial.println("WiFi failed");
	    delay(1000);
	  }
	
	  // MQTT
	  while(true) {
	    Serial.println("MQTT try");
	  
	    if (mqtt_client.connect(MQTT::Connect(MQTT_CLIENT_ID).set_keepalive(90).set_auth(String(MQTT_UNAME), String(MQTT_PASSW)))) {
	      mqtt_client.set_callback(mqtt_callback); //set callback on received messages
	      mqtt_client.set_max_retries(255);
	      if (mqtt_client.subscribe("/daffy/relay")) {
	        Serial.println("Subscription success");
	        break;
	      } else {
	        Serial.println("Subscription failed");
	        mqtt_client.disconnect();
	        delay(1000);
	        continue;
	      }
	    } else {
	      delay(1000);
	      continue;
	    }
	  }
	}
	
	void loop() {
	  char payload[20];
	  
	  //sprintf(payload,"Start");
	  //mqtt_client.publish("/daffy/input", payload);
	
	  if (mqtt_client.connected()) {
	        mqtt_client.loop();
	  }
	}

## Schematic

* [Daffy-4 schematic in PDF format](./daffy-4-schematic.pdf)

## Datasheet

* [Relay Panasonic ALQ112](http://www.farnell.com/datasheets/2245159.pdf)
* [Texas Instruments TCA9534A Low Voltage 8-Bit I2C and SMBUS Low-Power I/O Expander With Interrupt](https://www.ti.com/lit/ds/symlink/tca9534a.pdf)

@include='adv_relay'