Share SCL & SDA using arduino Pro mini

Does anyone know how to connect 2 sensors both using SCL/SDA?
And how to combine them in de sketch?

In my example (BH1750 & BMP085)

Thanks

Im using the example RelayWithButtonActuator:

/**
 * The MySensors Arduino library handles the wireless radio link and protocol
 * between your home built sensors/actuators and HA controller of choice.
 * The sensors forms a self healing radio network with optional repeaters. Each
 * repeater and gateway builds a routing tables in EEPROM which keeps track of the
 * network topology allowing messages to be routed to nodes.
 *
 * Created by Henrik Ekblad <henrik.ekblad@mysensors.org>
 * Copyright (C) 2013-2015 Sensnology AB
 * Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
 *
 * Documentation: http://www.mysensors.org
 * Support Forum: http://forum.mysensors.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 *******************************
 *
 * REVISION HISTORY
 * Version 1.0 - Henrik Ekblad
 * 
 * DESCRIPTION
 * Example sketch for a "light switch" where you can control light or something 
 * else from both HA controller and a local physical button 
 * (connected between digital pin 3 and GND).
 * This node also works as a repeader for other nodes
 * http://www.mysensors.org/build/relay
 */ 

#include <MySensor.h>
#include <SPI.h>
#include <Bounce2.h>

#define RELAY_PIN  4  // Arduino Digital I/O pin number for relay 
#define BUTTON_PIN  3  // Arduino Digital I/O pin number for button 
#define CHILD_ID 1   // Id of the sensor child
#define RELAY_ON 1
#define RELAY_OFF 0

Bounce debouncer = Bounce(); 
int oldValue=0;
bool state;
MySensor gw;
MyMessage msg(CHILD_ID,V_LIGHT);

void setup()  
{  
  gw.begin(incomingMessage, AUTO, true);

  // Send the sketch version information to the gateway and Controller
  gw.sendSketchInfo("Relay & Button", "1.0");

 // Setup the button
  pinMode(BUTTON_PIN,INPUT);
  // Activate internal pull-up
  digitalWrite(BUTTON_PIN,HIGH);
  
  // After setting up the button, setup debouncer
  debouncer.attach(BUTTON_PIN);
  debouncer.interval(5);

  // Register all sensors to gw (they will be created as child devices)
  gw.present(CHILD_ID, S_LIGHT);

  // Make sure relays are off when starting up
  digitalWrite(RELAY_PIN, RELAY_OFF);
  // Then set relay pins in output mode
  pinMode(RELAY_PIN, OUTPUT);   
      
  // Set relay to last known state (using eeprom storage) 
  state = gw.loadState(CHILD_ID);
  digitalWrite(RELAY_PIN, state?RELAY_ON:RELAY_OFF);
}


/*
*  Example on how to asynchronously check for new messages from gw
*/
void loop() 
{
  gw.process();
  debouncer.update();
  // Get the update value
  int value = debouncer.read();
  if (value != oldValue && value==0) {
      gw.send(msg.set(state?false:true), true); // Send new state and request ack back
  }
  oldValue = value;
} 
 
void incomingMessage(const MyMessage &message) {
  // We only expect one type of message from controller. But we better check anyway.
  if (message.isAck()) {
     Serial.println("This is an ack from gateway");
  }

  if (message.type == V_LIGHT) {
     // Change relay state
     state = message.getBool();
     digitalWrite(RELAY_PIN, state?RELAY_ON:RELAY_OFF);
     // Store state in eeprom
     gw.saveState(CHILD_ID, state);
    
     // Write some debug info
     Serial.print("Incoming change for sensor:");
     Serial.print(message.sensor);
     Serial.print(", New status: ");
     Serial.println(message.getBool());

   } 
}

just enabled led blinking for the gateway. When pressing relay sensor button: RX and TX blink on serial gateway + serial out:

send: 0-0-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0,st=ok:0
read: 0-0-0 s=1,c=1,t=2,pt=2,l=2,sg=0:0
This is an ack from gateway
Incoming change for sensor:1, New status: 0italicised text

When controlling with Domoticz or MYSController....nothing send to the serial gateway, no TX, RX

Spending hours without any progress

Is there something i did not configure? Just using the example sketch for the serial gateway and enabled Led's in myconfig

Im using the default example sketch 1.5.3:

/**
 * The MySensors Arduino library handles the wireless radio link and protocol
 * between your home built sensors/actuators and HA controller of choice.
 * The sensors forms a self healing radio network with optional repeaters. Each
 * repeater and gateway builds a routing tables in EEPROM which keeps track of the
 * network topology allowing messages to be routed to nodes.
 *
 * Created by Henrik Ekblad <henrik.ekblad@mysensors.org>
 * Copyright (C) 2013-2015 Sensnology AB
 * Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
 *
 * Documentation: http://www.mysensors.org
 * Support Forum: http://forum.mysensors.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 *******************************
 *
 * DESCRIPTION
 * The ArduinoGateway prints data received from sensors on the serial link. 
 * The gateway accepts input on seral which will be sent out on radio network.
 *
 * The GW code is designed for Arduino Nano 328p / 16MHz
 *
 * Wire connections (OPTIONAL):
 * - Inclusion button should be connected between digital pin 3 and GND  
 * - RX/TX/ERR leds need to be connected between +5V (anode) and digital pin 6/5/4 with resistor 270-330R in a series
 *
 * LEDs (OPTIONAL):
 * - To use the feature, uncomment WITH_LEDS_BLINKING in MyConfig.h
 * - RX (green) - blink fast on radio message recieved. In inclusion mode will blink fast only on presentation recieved
 * - TX (yellow) - blink fast on radio message transmitted. In inclusion mode will blink slowly
 * - ERR (red) - fast blink on error during transmission error or recieve crc error 
 * 
 */

#define NO_PORTB_PINCHANGES  

#include <MySigningNone.h>
#include <MyTransportRFM69.h>
#include <MyTransportNRF24.h>
#include <MyHwATMega328.h>
#include <MySigningAtsha204Soft.h>
#include <MySigningAtsha204.h>

#include <SPI.h>  
#include <MyParserSerial.h>  
#include <MySensor.h>  
#include <stdarg.h>
#include <PinChangeInt.h>
#include "GatewayUtil.h"

#define INCLUSION_MODE_TIME 1 // Number of minutes inclusion mode is enabled
#define INCLUSION_MODE_PIN  3 // Digital pin used for inclusion mode button
#define RADIO_ERROR_LED_PIN 4  // Error led pin
#define RADIO_RX_LED_PIN    6  // Receive led pin
#define RADIO_TX_LED_PIN    5  // the PCB, on board LED

// NRFRF24L01 radio driver (set low transmit power by default) 
MyTransportNRF24 transport(RF24_CE_PIN, RF24_CS_PIN, RF24_PA_LEVEL_GW);
//MyTransportRFM69 transport;

// Message signing driver (signer needed if MY_SIGNING_FEATURE is turned on in MyConfig.h)
//MySigningNone signer;
//MySigningAtsha204Soft signer;
//MySigningAtsha204 signer;

// Hardware profile 
MyHwATMega328 hw;

// Construct MySensors library (signer needed if MY_SIGNING_FEATURE is turned on in MyConfig.h)
// To use LEDs blinking, uncomment WITH_LEDS_BLINKING in MyConfig.h
#ifdef WITH_LEDS_BLINKING
MySensor gw(transport, hw /*, signer*/, RADIO_RX_LED_PIN, RADIO_TX_LED_PIN, RADIO_ERROR_LED_PIN);
#else
MySensor gw(transport, hw /*, signer*/);
#endif

char inputString[MAX_RECEIVE_LENGTH] = "";    // A string to hold incoming commands from serial/ethernet interface
int inputPos = 0;
boolean commandComplete = false;  // whether the string is complete

void parseAndSend(char *commandBuffer);

void output(const char *fmt, ... ) {
   va_list args;
   va_start (args, fmt );
   vsnprintf_P(serialBuffer, MAX_SEND_LENGTH, fmt, args);
   va_end (args);
   Serial.print(serialBuffer);
}

  
void setup()  
{ 
  gw.begin(incomingMessage, 0, true, 0);

  setupGateway(INCLUSION_MODE_PIN, INCLUSION_MODE_TIME, output);

  // Add interrupt for inclusion button to pin
  PCintPort::attachInterrupt(pinInclusion, startInclusionInterrupt, RISING);


  // Send startup log message on serial
  serial(PSTR("0;0;%d;0;%d;Gateway startup complete.\n"),  C_INTERNAL, I_GATEWAY_READY);
}

void loop()  
{ 
  gw.process();

  checkButtonTriggeredInclusion();
  checkInclusionFinished();
  
  if (commandComplete) {
    // A command wass issued from serial interface
    // We will now try to send it to the actuator
    parseAndSend(gw, inputString);
    commandComplete = false;  
    inputPos = 0;
  }
}


/*
  SerialEvent occurs whenever a new data comes in the
 hardware serial RX.  This routine is run between each
 time loop() runs, so using delay inside loop can delay
 response.  Multiple bytes of data may be available.
 */
void serialEvent() {
  while (Serial.available()) {
    // get the new byte:
    char inChar = (char)Serial.read(); 
    // if the incoming character is a newline, set a flag
    // so the main loop can do something about it:
    if (inputPos<MAX_RECEIVE_LENGTH-1 && !commandComplete) { 
      if (inChar == '\n') {
        inputString[inputPos] = 0;
        commandComplete = true;
      } else {
        // add it to the inputString:
        inputString[inputPos] = inChar;
        inputPos++;
      }
    } else {
       // Incoming message too long. Throw away 
        inputPos = 0;
    }
  }
}

Sorry..the last 2 blue lines in the picture are send via MYSController, but no result in serial output of the sensor or a relay ticking....( relay is working when pressing physical button )

Looking for some help with relay actuator and serial gateway.

Having setup multiple arduino's with NRF's all working well when sending data to the gateway.
For some reason no way to send anything to a sensor from the gateway with Domoticz or MYSController

Does anyone recognize an issue in the screenshot?
Using different Arduino's with different NRF's + Caps, 3.3v measured ( but according to serial log there is communication )

Thanks for the support!

I use this NRF modules:

http://www.ebay.com/itm/Mini-NRF24L01-SMD-1-27MM-wireless-transceiver-module-Small-Size-/400489040899?hash=item5d3f01cc03:g:OS8AAMXQaOVRk6PR

Small Update: seems that everything "sending" from domoticz is not received at the nodes.
When monitoring the serial from relay, dimmer, rgb....

when i tick devices in domoticz, a sensor is just not receiving:

send: 31-31-0-0 s=255,c=0,t=17,pt=0,l=5,sg=0,st=ok:1.5.1
send: 31-31-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,st=ok:0
sensor started, id=31, parent=0, distance=1
send: 31-31-0-0 s=255,c=3,t=11,pt=0,l=14,sg=0,st=ok:Relay & Button
send: 31-31-0-0 s=255,c=3,t=12,pt=0,l=3,sg=0,st=ok:1.0
send: 31-31-0-0 s=1,c=0,t=3,pt=0,l=0,sg=0,st=ok:

Thanks for the input, but this is not working for me

Yes it is switching, but initiated from the attached button