updated to work with updated library

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

.gitignore

@@ -0,0 +1 @@
+Gerber

README.md

@@ -1,3 +1,4 @@
 | Board | Button Interrupt | RS485-Interrupt | RS485/A | RS485/B |
 |-------|------------------|-----------------|---------|---------|
 | 1.0   |               D2 |              D3 |      U7 |      U8 |
+| 2.0   |               D2 |            (D10)|      U8 |      U7 |

Sender/Sender.ino

@@ -1,93 +0,0 @@
-// Breadboard
-//int enable = 2;
-//int sTx = 4;
-//int sRx = 5;
-
-// RS485-Nano Revision 1.0
-int enable = 9;
-int sTx = 8;
-int sRx = 3;
-
-long base = 100;
-
-int id = 0;
-int baud = 19200;
-char c;
-int counter = 0;
-
-void setup(){
-  pinMode(A0,INPUT);
-  id = analogRead(A0);
-  
-  pinMode(enable,OUTPUT);
-  digitalWrite(enable,LOW);
-  
-  pinMode(sTx,OUTPUT);
-  digitalWrite(sTx,LOW);
-  
-  pinMode(sRx,INPUT);
-  Serial.begin(115200);  
-  Serial.print("Baud rate set to ");
-  Serial.println(baud);
-  Serial.print("Initialized Arduino #");
-  Serial.println(id);
-}
-
-bool sendBit(bool bt){
-  digitalWrite(sTx,bt);
-  delayMicroseconds(80);
-  if (digitalRead(sTx) != bt) return false;
-  delayMicroseconds(base-80);
-  return true;
-}
-
-bool sendChar(char c){
-  return sendBit(c & 0x01)
-      && sendBit(c & 0x02)
-      && sendBit(c & 0x04)
-      && sendBit(c & 0x08)
-      && sendBit(c & 0x10)
-      && sendBit(c & 0x20)
-      && sendBit(c & 0x40)
-      && sendBit(c & 0x80);
-}
-
-bool sendString(String s){
-  Serial.print("Sending '"+s+"'…");
-  boolean busy = false;
-  for (int i = 0; i<11; i++){
-    if (!digitalRead(sRx)) {
-      if (!busy){
-        Serial.print("busy…");
-        busy = true;
-      }
-      i = 0; // wait for free line
-    }
-    delayMicroseconds(base);
-  }
-  digitalWrite(enable,HIGH);
-  bool success = sendBit(0); // erste Flanke erzeugen
-  if (success) {
-    for (char c : s){
-      if (!sendChar(c)){
-        success = false;
-        break;
-      }
-    }
-  }
-  success = success && sendChar(13);
-  success = success && sendBit(1); // letzte Flanke erzeugen
-  digitalWrite(enable,LOW);
-  Serial.println(success ? "success" : "failed");
-  return success;
-}
-
-void loop(){
-  counter++;
-  String s = "Hier ist ";
-  s.concat(id);
-  s+=": counter = ";
-  s.concat(counter);
-  while (!sendString(s)) delay(10*base);
-  delay(id);
-}

Software/BiDi/BiDi.ino

@@ -0,0 +1,95 @@
+/* RS 485-Implementierung, die sowohl Schreiben als auch Lesen kann */
+/* Basis für andere Projekte */
+
+#define BUTTON 2
+#define RECEIVE 3
+#define RECEIVE_ENABLE 4
+#define SEND 5
+#define SEND_ENABLE 6
+
+#define MAX_LEN 128
+
+void setup() {
+  // Buttons connected to analog input lines
+  pinMode(A0,INPUT_PULLUP);
+  pinMode(A1,INPUT_PULLUP);
+  pinMode(A2,INPUT_PULLUP);
+  pinMode(A3,INPUT_PULLUP);
+  pinMode(A4,INPUT_PULLUP);
+  pinMode(A5,INPUT_PULLUP);
+  pinMode(A6,INPUT_PULLUP);
+  pinMode(A7,INPUT_PULLUP);
+  // Currently, all buttons are also connected via a diode to an interruptable pin, to notify on input changes.
+  // This interruptable pin should be assgined to BUTTON
+  pinMode(BUTTON,INPUT_PULLUP);
+  attachInterrupt(digitalPinToInterrupt(BUTTON),button,FALLING); // interrupt for button change
+
+  // Set up pins for RS485 connection
+  pinMode(RECEIVE, INPUT);
+  pinMode(RECEIVE_ENABLE, OUTPUT);
+  pinMode(SEND, OUTPUT);
+  pinMode(SEND_ENABLE, OUTPUT);
+  attachInterrupt(digitalPinToInterrupt(RECEIVE),receive,CHANGE); // interrupt for incoming RS485 traffic
+  
+  reset485();
+  buttons = 0x0;
+}
+
+void button() {
+  buttons = 0xFF ^ (digitalRead(A7)<<7 | digitalRead(A6)<<6 | digitalRead(A5)<<5 | digitalRead(A4)<<4 | digitalRead(A3)<<3 | (!digitalRead(A2))<<2 | digitalRead(A1)<<1 | digitalRead(A0));  
+}
+
+void receive(){
+  bool received_bit = digitalRead(RECEIVE);
+  curr = micros();
+  duration = curr - last;
+  Serial.print("Input switched to ");
+  Serial.print(received_bit?"H":"L");  
+  Serial.print(" after ");
+  Serial.print(duration);
+  Serial.println(" ticks");
+  last = curr;
+  if (duration > MAX_TICKS) reset485();
+  received_bit = !received_bit; // received_bit is the current value, the duration of the previous value (=inverted) has been measured
+  duration /= BASE;
+  while (duration > 0){
+    byte_idx--;
+    recv |= received_bit<<byte_idx;
+    if (byte_idx == 0) {
+      msg[msg_idx] = recv;
+      msg_idx++;
+      byte_idx = 8;
+      if (recv == 0x00) message_received();
+    }
+    duration--;
+  }
+}
+
+void reset485(){
+  byte_idx = 8;
+  msg_idx = 0;
+  recv=0x0;
+}
+
+void message_received(){
+  for (int i=0; i<MAX_LEN; i++) message[i]=msg[i];
+  reset485();
+}
+
+void button_pressed(int i){
+  Serial.println("not implemented");
+}
+
+void loop(){
+  if (buttons>0){
+    for (int i=0; i<7; i++){
+      if (buttons & (1<<i)) button_pressed(i);     
+    }    
+  }
+  if (message[0] != 0x0){
+    Serial.print("Received '");
+    Serial.print(message);
+    Serial.println("'");    
+    message[0] = 0x0;
+  }
+}

Software/LCDReceiver/LCDReceiver.ino

@@ -0,0 +1,60 @@
+/*
+ *  Demonstrates how to use LCDisplay in conjunction with SoftRS485:
+ *
+ *  The main _loop_ of this program listens on the RS485 bus.
+ *  Whenever a message is received from the bus, it is displayed on the LCD.
+ */
+
+// include the library code:
+#include <LiquidCrystal.h>
+#include <SoftRS485.h>
+
+#define PROGRAM "RS485-Nano Rev 2.0 / LCDReceive 1.2"
+
+#define Max485_RO 3 // read-output of Max485
+#define Max485_RE 5 // not-read-enable of Max485
+#define Max485_DE 9 // data enable of Max485
+#define Max485_DI 8 // data input of Max485
+
+#define LCD_RS 4
+#define LCD_EN 6
+#define LCD_D4 7
+#define LCD_D5 11
+#define LCD_D6 12
+#define LCD_D7 13
+
+// initialize the library by associating any needed LCD interface pin with the arduino pin number it is connected to
+LiquidCrystal lcd(LCD_RS, LCD_EN, LCD_D4, LCD_D5, LCD_D6, LCD_D7);
+
+void setup() {
+  Serial.begin(115200);
+  init485(Max485_RO,Max485_RE,Max485_DE,Max485_DI); // library initialization:
+  // set up the LCD's number of columns and rows:
+  lcd.begin(16, 2);
+  // Print a message to the LCD.
+  printMessage(PROGRAM);
+}
+
+void printMessage(String s){
+    Serial.println(s);
+    lcd.clear();    
+    int line = 0;
+    int col = 0;
+    auto cstr = s.c_str();
+    for (int i=0;i<s.length();i++){
+      if (col == 0 && cstr[i] == ' ') continue;
+      lcd.print(cstr[i]);
+      col++;
+      if (cstr[i]==',' || col==16){
+        line++;
+        col=0;
+        lcd.setCursor(col, line);
+      }
+    }
+}
+
+void loop() {
+  if (available485()) {
+    printMessage(get485message());
+  }
+}

Software/ManualSend/ManualSend.ino

@@ -0,0 +1,85 @@
+/*// This sketch allows manual setting of the RS485-connected pins via serial terminal commands
+
+Commands are:
+r+ – enable read mode (^RE ← LOW)
+r- – disable read mode (^RE ← HIGH)
+w+ – enable write mode (DE ← HIGH)
+w- – disable write mode (DE ← LOW)
+h  – send HIGH level on DI
+l  – send LOW level on DI
+
+//*/
+
+#if defined(ARDUINO_AVR_UNO)
+  #define RS485_RO 5
+  #define RS485_RE 4
+  #define RS485_DE 3
+  #define RS485_DI 2
+  #define BOARD "Arduino Uno"
+#endif
+#if defined(ARDUINO_AVR_NANO)
+  #define RS485_RO 3
+  #define RS485_RE 2
+  #define RS485_DE 4
+  #define RS485_DI 5
+  #define BOARD "Arduino Nano"
+#endif
+
+String command = "";
+bool doPrint = false;
+// the setup function runs once when you press reset or power the board
+void setup() {
+  // initialize digital pin LED_BUILTIN as an output.
+  pinMode(RS485_RO, INPUT);
+  pinMode(RS485_RE, OUTPUT);
+  pinMode(RS485_DE, OUTPUT);
+  pinMode(RS485_DI, OUTPUT);
+  digitalWrite(RS485_RE,LOW);
+  digitalWrite(RS485_DE,LOW);
+  digitalWrite(RS485_DI,LOW);
+  Serial.begin(115200);
+  Serial.println(F("this is Projekte/Arduino/MAX485/ManualSend"));
+  Serial.println(F("send any of the followning commands:"));
+  Serial.println(F("- r+ (enable read)\n- r- (disable read)\n- w+ (enable write)\n- w- (disable write)\n- h (for high)\n- l (for low)"));
+}
+
+// the loop function runs over and over again forever
+void loop() {
+  while (Serial.available()){
+    char inChar = (char)Serial.read();
+    if (inChar == '\n') {
+      process(command);
+      command = ""; 
+      doPrint = true;
+    } else {
+      command += inChar;
+    }
+  }
+  if (doPrint){
+    printState();
+    delay(1000);
+  }
+}
+
+void printState(){
+  Serial.print("RE = ");
+  Serial.print(1-digitalRead(RS485_RE));
+  Serial.print(", DE = ");
+  Serial.print(digitalRead(RS485_DE));
+  Serial.print(", DI = ");
+  Serial.print(digitalRead(RS485_DI));
+  Serial.print(", RO = ");
+  Serial.println(digitalRead(RS485_RO));
+}
+
+void process(String command){
+  Serial.print(F("received:"));
+  Serial.println(command);
+  if (command == "r+") digitalWrite(RS485_RE,LOW);
+  if (command == "r-") digitalWrite(RS485_RE,HIGH);
+  if (command == "w+") digitalWrite(RS485_DE,HIGH);
+  if (command == "w-") digitalWrite(RS485_DE,LOW);
+  if (command == "h") digitalWrite(RS485_DI,HIGH);
+  if (command == "l") digitalWrite(RS485_DI,LOW);
+  printState();
+}

Software/ManualSend/Readme.md

@@ -0,0 +1,4 @@
+Erkenntnisse:
+
+1. Wenn alle Treiber inaktiv sind, also bei allen Teilnehmer DI = Low ist, kommt vom RO ein High-Signal
+2. das High-Signal ist dominant, d.h. wenn mehrere Teilnehmer senden, und mindestens ein Teilnehmer eine 1 auf den Bus legt, erhalten alle am RO einen HIGH-Pegel

Software/Receiver/Receiver.ino

@@ -1,3 +1,5 @@
+// Für Controllino könnte man benutzen: sRx = 20, sTx = 21, enable = 53
+
 int sTx = 2;
 int sRx = 3;
 
@@ -13,34 +15,34 @@ String message;
 void setup(){
   pinMode(sRx,INPUT);
   pinMode(sTx,OUTPUT);
-  attachInterrupt(digitalPinToInterrupt(sRx),change,CHANGE);
+  attachInterrupt(digitalPinToInterrupt(sRx),change485,CHANGE);
   Serial.begin(115200);  
   Serial.println("Receiver ready");
 }
 
-void reset(long dif){
+void reset485(long dif){
     rcv = 0;
     idx = -1;
     message.reserve(32);
 }
-void change(){
+void change485(){
   bool bt = digitalRead(sRx);
   now = micros();
   dif = now - lt;
   lt = now;
   if (dif > rst){
-    reset(dif);
+    reset485(dif);
   } else {
-    handle(!bt,dif);
+    handle485(!bt,dif);
   }
 }
 
-void handle(boolean bt, long dif){
+void handle485(boolean bt, long dif){
   long count = dif/base;
-  for (int i=0; i<count; i++) push(bt);
+  for (int i=0; i<count; i++) push485(bt);
 }
 
-void push(boolean bt){
+void push485(boolean bt){
   if (idx>=0) rcv |= bt<<idx;
   idx++;
   

Software/Sender/Sender.ino

@@ -0,0 +1,124 @@
+/*
+ *  Demonstrates how to use Read Buttons in conjunction with SoftRS485:
+ *
+ * If a button is pressed, a corresponding flag is set.
+ * The main loop checks for the state of those flags and
+ * sends a message on the RS485 bus whenever a flag is set.
+ */
+
+// include the library code:
+#include <SoftRS485.h>
+
+// 0=Test
+// 1=Flur
+// 2=Wohnzimmer
+// 3=Bad EG
+// 4=Treppenhaus
+// 5=Arbeitszimmer
+// 6=Bad OG
+
+#define ID 0
+#define PROGRAM "Sender"
+#define SW_VERSION "1.3"
+#define HW_VERSION "2.0"
+
+#define BTN_INT 2 // button interrupt pin
+#define Max485_RO 3 // read-output of Max485
+#define Max485_RE 5 // not-read-enable of Max485
+#define Max485_DE 9 // data enable of Max485
+#define Max485_DI 8 // data input of Max485
+
+#define TRESHOLD 1024
+#define TRIGGER_LEVEL 200
+
+//#define DEBUG
+//#define LOG_TO_SERIAL
+#define SEND_485
+
+boolean raw_states[8];
+boolean states[8];
+unsigned long capacitor[8];
+unsigned long times[8];
+
+
+
+void setup(){
+  for (int i=0; i<8;i++) {
+    capacitor[i] = 0;
+    raw_states[i] = LOW;
+    states[i] = LOW;
+  }
+  Serial.begin(115200);
+  init485(Max485_RO,Max485_RE,Max485_DE,Max485_DI,6000); // library initialization:
+  pinMode(BTN_INT,INPUT_PULLUP);
+  pinMode(14,INPUT_PULLUP);
+  pinMode(15,INPUT_PULLUP);
+  pinMode(16,INPUT_PULLUP);
+  pinMode(17,INPUT_PULLUP);
+  pinMode(18,INPUT_PULLUP);
+  pinMode(19,INPUT_PULLUP);
+  pinMode(20,INPUT_PULLUP);
+  pinMode(21,INPUT_PULLUP);
+
+  attachInterrupt(digitalPinToInterrupt(BTN_INT),isr,CHANGE);
+  String s = "{nano:"+String(ID)+",hw:"+HW_VERSION+","+PROGRAM+":"+SW_VERSION+"}";
+  Serial.println(s);
+  send485(s.c_str());
+#ifdef LOG_TO_SERIAL
+  Serial.println("14 15 16 17 18 19 20 21");
+#endif
+}
+
+void isr(){
+  raw_states[0] = analogRead(14)<TRIGGER_LEVEL;
+  raw_states[1] = analogRead(15)<TRIGGER_LEVEL;
+  raw_states[2] = analogRead(16)<TRIGGER_LEVEL;
+  raw_states[3] = analogRead(17)<TRIGGER_LEVEL;
+
+  raw_states[4] = analogRead(18)<TRIGGER_LEVEL;
+  raw_states[5] = analogRead(19)<TRIGGER_LEVEL;
+  raw_states[6] = analogRead(20)<TRIGGER_LEVEL;
+  raw_states[7] = analogRead(21)<TRIGGER_LEVEL;
+#ifdef LOG_TO_SERIAL
+  for (int i=0;i<8;i++){
+    Serial.print(" ");    
+    Serial.print(raw_states[i]);
+    Serial.print(" ");
+  }
+  Serial.println();
+#endif
+}
+
+void send(int btn, long duration){
+  String s = "{nano:"+String(ID)+",btn:"+String(btn)+",ms:"+String(duration)+"}";
+#ifdef SEND_485
+  for (int i = 0; i<10; i++){
+    if (send485(s.c_str())) break;
+    Serial.println("collision detected, trying again:");
+  }
+#else
+  Serial.println(s);
+#endif
+}
+
+void loop(){
+  unsigned long now = micros();
+  for (int i=0;i<8;i++){
+    // we emulate a capacitor:
+    // when the button is pressed, it slowly loads, if the button is released, it unloads.
+    capacitor[i] = raw_states[i] ? capacitor[i]+1 : capacitor[i]>>1;
+
+    // if the capacitor reaches a certain treshold, the state is changed
+    boolean new_state = capacitor[i]>TRESHOLD;
+
+    // TODO: drop state after a maximum HIGH time
+
+    // when the state changes, the duration of the last state is calculated
+    if (states[i] != new_state){      
+      long diff = (now - times[i])/1000;
+      times[i] = now;
+      if (states[i]) send(i+1,diff); // old state was HIGH → we are going LOW
+      states[i] = new_state;
+    }
+  }
+}

Software/SerialTransceiver/SerialTransceiver.ino

@@ -0,0 +1,37 @@
+/*
+ *  Demonstrates how to use LCDisplay in conjunction with SoftRS485:
+ *
+ *  The main _loop_ of this program listens on the RS485 bus.
+ *  Whenever a message is received from the bus, it is displayed on the LCD.
+ */
+
+// include the library code:
+#include <SoftRS485.h>
+
+#define Max485_RO 3 // read-output of Max485
+#define Max485_RE 5 // not-read-enable of Max485
+#define Max485_DE 9 // data enable of Max485
+#define Max485_DI 8 // data input of Max485
+
+#define PROGRAM "{hw:RS485-Nano rev 2.0,firmware:Transceiver,version:1.1}"
+String message = "";
+char c;
+void setup() {
+  Serial.begin(115200);
+  Serial.println(PROGRAM);
+  init485(Max485_RO,Max485_RE,Max485_DE,Max485_DI,6000); // library initialization:
+  send485(PROGRAM);
+}
+
+void loop() {
+  if (available485()) Serial.println(get485message());
+  while (Serial.available()) {
+    c = (char)Serial.read();
+    if (c == '\n') {
+      send485(message.c_str());
+      message = "";
+    } else {
+      message += c;    
+    }
+  }  
+}

Software/TempSender/TempSender.ino

@@ -0,0 +1,142 @@
+/*
+ *  Demonstrates how to use Read Buttons in conjunction with SoftRS485:
+ *
+ * If a button is pressed, a corresponding flag is set.
+ * The main loop checks for the state of those flags and
+ * sends a message on the RS485 bus whenever a flag is set.
+ * 
+ * Additionally, the temperature is read from a DHT22 sensor once per minute
+ */
+
+// include the library code:
+#include <SoftRS485.h>
+#include <SimpleDHT.h>
+
+// 0=Test
+// 1=Flur
+// 2=Wohnzimmer
+// 3=Bad EG
+// 4=Treppenhaus
+// 5=Arbeitszimmer
+// 6=Bad OG
+
+#define ID 0
+#define HW_VERSION "2.0"
+#define PROGRAM "TempSender"
+#define SW_VERSION "1.5"
+
+#define BTN_INT 2 // button interrupt pin
+#define Max485_RO 3 // read-output of Max485
+#define Max485_RE 5 // not-read-enable of Max485
+#define Max485_DE 9 // data enable of Max485
+#define Max485_DI 8 // data input of Max485
+
+#define TRESHOLD 1024
+#define TRIGGER_LEVEL 200
+
+#define DHT_PIN 4
+#define PERIOD   100000000 // 100s
+
+//#define DEBUG
+//#define LOG_TO_SERIAL
+#define SEND_485
+
+boolean raw_states[8];
+boolean states[8];
+unsigned long capacitor[8];
+unsigned long times[8];
+unsigned long sensor_time = 0;
+
+SimpleDHT22 sensor(DHT_PIN);
+float temperature = 0;
+float humidity = 0;
+int err = SimpleDHTErrSuccess;
+
+void setup(){
+  for (int i=0; i<8;i++) {
+    capacitor[i] = 0;
+    raw_states[i] = LOW;
+    states[i] = LOW;
+  }
+  Serial.begin(115200);
+  init485(Max485_RO,Max485_RE,Max485_DE,Max485_DI); // library initialization:
+  pinMode(BTN_INT,INPUT_PULLUP);
+  pinMode(14,INPUT_PULLUP);
+  pinMode(15,INPUT_PULLUP);
+  pinMode(16,INPUT_PULLUP);
+  pinMode(17,INPUT_PULLUP);
+  pinMode(18,INPUT_PULLUP);
+  pinMode(19,INPUT_PULLUP);
+  pinMode(20,INPUT_PULLUP);
+  pinMode(21,INPUT_PULLUP);
+
+  attachInterrupt(digitalPinToInterrupt(BTN_INT),isr,CHANGE);
+  String s = "{nano:"+String(ID)+",hw:"+HW_VERSION+","+PROGRAM+":"+SW_VERSION+"}";
+  Serial.println(s);
+  send485(s.c_str());
+#ifdef LOG_TO_SERIAL
+  Serial.println("14 15 16 17 18 19 20 21");
+#endif
+}
+
+void isr(){
+  raw_states[0] = analogRead(14)<TRIGGER_LEVEL;
+  raw_states[1] = analogRead(15)<TRIGGER_LEVEL;
+  raw_states[2] = analogRead(16)<TRIGGER_LEVEL;
+  raw_states[3] = analogRead(17)<TRIGGER_LEVEL;
+
+  raw_states[4] = analogRead(18)<TRIGGER_LEVEL;
+  raw_states[5] = analogRead(19)<TRIGGER_LEVEL;
+  raw_states[6] = analogRead(20)<TRIGGER_LEVEL;
+  raw_states[7] = analogRead(21)<TRIGGER_LEVEL;
+#ifdef LOG_TO_SERIAL
+  for (int i=0;i<8;i++){
+    Serial.print(" ");    
+    Serial.print(raw_states[i]);
+    Serial.print(" ");
+  }
+  Serial.println();
+#endif
+}
+
+void send(int btn, long duration){
+  String s = "{nano:"+String(ID)+",btn:"+String(btn)+",ms:"+String(duration)+"}";
+#ifdef SEND_485
+  for (int i = 0; i<10; i++){
+    if (send485(s.c_str())) break;
+    Serial.println("collision detected, trying again:");
+  }
+#else
+  Serial.println(s);
+#endif
+}
+
+void loop(){
+  unsigned long now = micros();
+  for (int i=0;i<8;i++){
+    // we emulate a capacitor:
+    // when the button is pressed, it slowly loads, if the button is released, it unloads.
+    capacitor[i] = raw_states[i] ? capacitor[i]+1 : capacitor[i]>>1;
+
+    // if the capacitor reaches a certain treshold, the state is changed
+    boolean new_state = capacitor[i]>TRESHOLD;
+
+    // TODO: drop state after a maximum HIGH time
+
+    // when the state changes, the duration of the last state is calculated
+    if (states[i] != new_state){      
+      long diff = (now - times[i])/1000;
+      times[i] = now;
+      if (states[i]) send(i+1,diff); // old state was HIGH → we are going LOW
+      states[i] = new_state;
+    }
+  }
+
+  if (now - sensor_time > PERIOD){
+    sensor_time = now;
+    if ((err = sensor.read2(&temperature, &humidity, NULL)) == SimpleDHTErrSuccess) {
+      String s = "{nano:"+String(ID)+",temp:"+String(temperature,1)+",humi:"+String(humidity,1)+"}";
+      send485(s.c_str());
+    }
+  }
+}

Software/TempSenderPlusIR/TempSenderPlusIR.ino

@@ -0,0 +1,194 @@
+/*
+ *  Demonstrates how to use Read Buttons in conjunction with SoftRS485:
+ *
+ * If a button is pressed, a corresponding flag is set.
+ * The main loop checks for the state of those flags and
+ * sends a message on the RS485 bus whenever a flag is set.
+ * 
+ * Additionally, the temperature is read from a DHT22 sensor once per minute
+ */
+
+// include the library code:
+#include <SoftRS485.h>
+#include <SimpleDHT.h>
+#include <TinyIRSender.hpp>
+
+// 0=Test
+// 1=Flur
+// 2=Wohnzimmer
+// 3=Bad EG
+// 4=Treppenhaus
+// 5=Arbeitszimmer
+// 6=Bad OG
+
+#define ID 0
+#define PROGRAM "Temp+IR"
+#define SW_VERSION "0.1"
+#define HW_VERSION "2.0"
+
+#define BTN_INT 2 // button interrupt pin
+#define Max485_RO 3 // read-output of Max485
+#define Max485_RE 5 // not-read-enable of Max485
+#define Max485_DE 9 // data enable of Max485
+#define Max485_DI 8 // data input of Max485
+
+#define TRESHOLD 1024
+#define TRIGGER_LEVEL 200
+
+#define DHT_PIN 4
+#define PERIOD   100000000 // 100s
+
+#define IR_PIN 5
+#define REPEATS 2
+
+//#define DEBUG
+//#define LOG_TO_SERIAL
+#define SEND_485
+
+boolean raw_states[8];
+boolean states[8];
+unsigned long capacitor[8];
+unsigned long times[8];
+unsigned long sensor_time = 0;
+
+// these values are used for temperature processing
+SimpleDHT11 sensor(DHT_PIN);
+byte temperature = 0;
+byte humidity = 0;
+int err = SimpleDHTErrSuccess;
+
+// these constants are used for message parsing in handle(message)
+const char* outer_delimiter = "{,}";
+const char* inner_delimiter = ":";
+
+void setup(){
+  for (int i=0; i<8;i++) {
+    capacitor[i] = 0;
+    raw_states[i] = LOW;
+    states[i] = LOW;
+  }
+  Serial.begin(115200);
+  init485(Max485_RO,Max485_RE,Max485_DE,Max485_DI); // library initialization:
+  pinMode(BTN_INT,INPUT_PULLUP);
+  pinMode(14,INPUT_PULLUP);
+  pinMode(15,INPUT_PULLUP);
+  pinMode(16,INPUT_PULLUP);
+  pinMode(17,INPUT_PULLUP);
+  pinMode(18,INPUT_PULLUP);
+  pinMode(19,INPUT_PULLUP);
+  pinMode(20,INPUT_PULLUP);
+  pinMode(21,INPUT_PULLUP);
+
+  attachInterrupt(digitalPinToInterrupt(BTN_INT),isr,CHANGE);
+  String s = "{nano:"+String(ID)+",hw:"+HW_VERSION+","+PROGRAM+":"+SW_VERSION+"}";
+  Serial.println(s);
+  send485(s.c_str());
+#ifdef LOG_TO_SERIAL
+  Serial.println("14 15 16 17 18 19 20 21");
+#endif
+}
+
+void isr(){
+  raw_states[0] = analogRead(14)<TRIGGER_LEVEL;
+  raw_states[1] = analogRead(15)<TRIGGER_LEVEL;
+  raw_states[2] = analogRead(16)<TRIGGER_LEVEL;
+  raw_states[3] = analogRead(17)<TRIGGER_LEVEL;
+
+  raw_states[4] = analogRead(18)<TRIGGER_LEVEL;
+  raw_states[5] = analogRead(19)<TRIGGER_LEVEL;
+  raw_states[6] = analogRead(20)<TRIGGER_LEVEL;
+  raw_states[7] = analogRead(21)<TRIGGER_LEVEL;
+#ifdef LOG_TO_SERIAL
+  for (int i=0;i<8;i++){
+    Serial.print(" ");    
+    Serial.print(raw_states[i]);
+    Serial.print(" ");
+  }
+  Serial.println();
+#endif
+}
+
+void send(int btn, long duration){
+  String s = "{nano:"+String(ID)+",btn:"+String(btn)+",ms:"+String(duration)+"}";
+#ifdef SEND_485
+  for (int i = 0; i<10; i++){
+    if (send485(s.c_str())) break;
+    Serial.println("collision detected, trying again:");
+  }
+#else
+  Serial.println(s);
+#endif
+}
+
+
+
+
+void handle(String message){
+#ifdef LOG_TO_SERIAL
+  Serial.println(message);
+#endif   
+  unsigned int ir_cmd = 0;
+  unsigned int ir_addr = 0;
+  unsigned int nano = 0;
+
+  const char* outer_state = NULL;
+  const char* inner_state = NULL;  
+  char* token = strtok_r(message.c_str(), outer_delimiter, &outer_state);
+  
+  while (token != NULL) {    
+    char* key = strtok_r(token,inner_delimiter,&inner_state);
+    char* val = strtok_r(NULL,inner_delimiter,&inner_state);
+    if (strcmp(key,"nano")==0) nano = atoi(val);      
+    if (strcmp(key,"addr")==0) ir_addr = atoi(val);
+    if (strcmp(key,"ir")==0) ir_cmd = atoi(val);
+    token=strtok_r(NULL, outer_delimiter, &outer_state);
+  }
+  
+  if (nano == ID){ // the message is addressed to us!
+ 
+    if (ir_addr && ir_cmd){
+#ifdef LOG_TO_SERIAL
+      Serial.print("Sending 0x");
+      Serial.print(ir_cmd,HEX);
+      Serial.print(" to 0x");
+      Serial.println(ir_addr,HEX);
+#endif
+      sendNECMinimal(IR_PIN, ir_addr, ir_cmd, REPEATS);
+     }
+  }
+}
+
+void loop(){
+  unsigned long now = micros();
+  for (int i=0;i<8;i++){
+    // we emulate a capacitor:
+    // when the button is pressed, it slowly loads, if the button is released, it unloads.
+    capacitor[i] = raw_states[i] ? capacitor[i]+1 : capacitor[i]>>1;
+
+    // if the capacitor reaches a certain treshold, the state is changed
+    boolean new_state = capacitor[i]>TRESHOLD;
+
+    // TODO: drop state after a maximum HIGH time
+
+    // when the state changes, the duration of the last state is calculated
+    if (states[i] != new_state){      
+      long diff = (now - times[i])/1000;
+      times[i] = now;
+      if (states[i]) send(i+1,diff); // old state was HIGH → we are going LOW
+      states[i] = new_state;
+    }
+  }
+
+  if (now - sensor_time > PERIOD){
+    sensor_time = now;
+    if ((err = sensor.read(&temperature, &humidity, NULL)) == SimpleDHTErrSuccess) {
+      String s = "{nano:"+String(ID)+",temp:"+String((int)temperature)+",humi:"+String((int)humidity)+"}";
+#ifdef LOG_TO_SERIAL
+      Serial.println(s);
+#endif
+      send485(s.c_str());
+    }
+  }
+  
+  if (available485()) handle(get485message());
+}