Scrolling Text sensor node with new V_TEXT

[AWI]

@Hoffan you best read the instructions for the development branch. The syntax changed a little. I'm typing on a phone right now. Best to search yourself

[hek]

How to convert a sketch to 1.6 is described here (until it has been posted somewhere more sticky..) :
https://docs.google.com/document/d/1NKq5uuNdnxF5jWnum7VT32mbKLjuvqlx2A5D1qQ-H3Q/edit#heading=h.t5sdmpn6jz2i

Basically a few search/replace... The above sketch would look something like this (untested)

/*
 PROJECT: MySensors / Scrolling Text display
 PROGRAMMER: AWI
 DATE: september 12, 2015/ last update: september 12, 2015
 FILE: AWI_scroll_MAX.ino
 LICENSE: Public domain

 Hardware: tbd ..Ceech - ATmega328p board w/ NRF24l01
    and MySensors 1.5 ()
        
Special:
    Need to use MySensors development edition 
    
SUMMARY:
    3 S_xx devices for scrolling text
    - Displays a scrolling text from a "V_TEXT" variable
    - additional dimmer sensor for controlling display brightness
    - 'Alarm' switch. If "On", overrides the text display to display ALARM message
    - You can also input messages from the Serial monitor (testing)
    Uses excellent MD_MAX72XX library 
 Remarks:
    Fixed node-id
*/

#define MY_RADIO_NRF24


// Use the MD_MAX72XX library to scroll text on the display with the use of the callback function 
// to control what is scrolled on the display text.
// You need to set the used display in the library MD_MAX72XX.h
// User can enter text on the serial monitor and this will display as a
// Speed for the display is controlled by a pot on SPEED_IN analog in.
#include <MD_MAX72xx.h>                     // multipurpose library for MAX72xx diaplay driver  https://parola.codeplex.com/
#include <MySensor.h>                       // Mysensor network
#include <SPI.h>
#include <Time.h>                           //http://playground.arduino.cc/Code/Time
#define USE_POT_CONTROL 0                   // enable Scroll speed  potentiometer
#define PRINT_CALLBACK  0

// Macro to simplify serial print
#define PRINT(s, v) { Serial.print(F(s)); Serial.print(v); }

// Define the number of devices we have in the chain and the hardware interface
// need to be adapted to your setup
const int MAX_DEVICES = 8 ;                 // number of 8x8 displays
const int CLK_PIN = 7 ;                     // SPI like clock
const int DATA_PIN = 8 ;                    // SPI like data
const int CS_PIN = 6 ;                      // SPI like select

// Parola is able to use SPI hardware interface, not testted in combination with MySensors
// MD_MAX72XX mx = MD_MAX72XX(CS_PIN, MAX_DEVICES);
// now use Arbitrary pins
MD_MAX72XX mx = MD_MAX72XX(DATA_PIN, CLK_PIN, CS_PIN, MAX_DEVICES); // instantiate one display chain

// Scrolling parameters, you can attach normal potentiometer to A5, Vcc, Gnd
#if USE_POT_CONTROL
const int SPEED_IN = A5 ;
#else
const int SCROLL_DELAY = 20 ;               // in milliseconds
#endif // USE_POT_CONTROL

const int CHAR_SPACING = 1 ;                // pixels between characters

// MySensors constants & variables
const byte nodeId = 51 ;                    // MySensors fixed node id
const byte messageCHILD = 8 ;               // Text from ControllerLCD
const byte brightnessChild = 9 ;            // Brightness of display
const byte alarmChild = 10 ;                // Display Alarm text (overrides normal text)
boolean timeReceived = false ;              // Flag to indicate time received
// Display constants & variables
byte textBrightness = 1 ;                   // brightness of display (between 0 - MAX_INTENSITY (0xF)
byte textOnOff = true ;                     // textOnOff = ! shutdown
boolean textAlarm = false ;                 // Alarm (switch S_BINARY)
// Global message buffers shared by MySensors and Scrolling functions
const int BUF_SIZE = 25 ;                   // max payload for MySensors(NRF24l01)
char curMessage[BUF_SIZE];                  // current displayed message
char newMessage[BUF_SIZE];                  // next message to be displayed if available
bool newMessageAvailable = false ;          // new message available flag
uint16_t    scrollDelay;                    // in milliseconds

// *** Definition and initialisation
// define the MySensor network (1.5)
// Initialize messages for sensor network
MyMessage textMsg(messageCHILD, V_TEXT);    // message for Sending Text to Controller


/* MD_MAX72XX functions: can be found in the documentation for the library,
 * no need to customtize callback & scroll routines (unless you want to...)
*/
uint8_t scrollDataSource(uint8_t dev, MD_MAX72XX::transformType_t t)
// Callback function for data that is required for scrolling into the display
{
  static char       *p = curMessage;
  static uint8_t    state = 0;
  static uint8_t    curLen, showLen;
  static uint8_t    cBuf[8];
  uint8_t colData;

  // finite state machine to control what we do on the callback
  switch(state)
  {
    case 0: // Load the next character from the font table
      showLen = mx.getChar(*p++, sizeof(cBuf)/sizeof(cBuf[0]), cBuf);
      curLen = 0;
      state++;

      // if we reached end of message, reset the message pointer
      if (*p == '\0')
      {
        p = curMessage;         // reset the pointer to start of message
        if (newMessageAvailable)    // there is a new message waiting
        {
          strcpy(curMessage, newMessage);   // copy it in
          newMessageAvailable = false;
        }
      }
      // !! deliberately fall through to next state to start displaying

    case 1: // display the next part of the character
      colData = cBuf[curLen++];
      if (curLen == showLen)                // end of character insert interchar space
      {
        showLen = CHAR_SPACING;
        curLen = 0;
        state = 2;
      }
      break;

    case 2: // display inter-character spacing (blank column)
      colData = 0;
      curLen++;
      if (curLen == showLen)
        state = 0;
      break;

    default:
      state = 0;
  }

  return(colData);
}

// Callback (not used here)
void scrollDataSink(uint8_t dev, MD_MAX72XX::transformType_t t, uint8_t col){
// Callback function for data that is being scrolled off the display
#if PRINT_CALLBACK
    Serial.print("\n cb ");
    Serial.print(dev);
    Serial.print(' ');
    Serial.print(t);
    Serial.print(' ');
    Serial.println(col);
#endif
}

// non-blocking text display to be used in loop (call frequently)
void scrollText(void){
    static uint32_t prevTime = 0;
    if (millis()-prevTime >= scrollDelay){                  // Is it time to scroll the text?
        mx.transform(MD_MAX72XX::TSL);                      // scroll along - the callback will load all the data
        prevTime = millis();                                // starting point for next time
        }
    }

// sets the scroll delay (read from potentiometer if enabled)
uint16_t getScrollDelay(void){
#if USE_POT_CONTROL
    uint16_t t = analogRead(SPEED_IN);
    t = map(t, 0, 1023, 25, 250);
    return(t);
#else
    return(SCROLL_DELAY);
#endif
    }

void setup(){
    // set up the display first
    mx.begin();                                             // initialize display chain                 
    mx.setShiftDataInCallback(scrollDataSource);            // define function to get the scrolldata (returned as int8)
    //mx.setShiftDataOutCallback(scrollDataSink);           // not used
    mx.control(MD_MAX72XX::INTENSITY, 0x01);
#if USE_POT_CONTROL                                         // initialize speed potentiometer if enabled
    pinMode(SPEED_IN, INPUT);
#else
    scrollDelay = SCROLL_DELAY;
#endif

    strcpy(curMessage, "I \x03 MySensors ");                // first message on display
    newMessage[0] = '\0';                                   // new message initialized to empty
    // Setup MySensors 
   //Serial in Sensor network = 115200
    //Send the sensor node sketch version information to the gateway

} 

void presentation() {

    sendSketchInfo("AWI Scroll MAX 51", "1.1");
    present(messageCHILD, S_INFO, "Text line Scroll");   // new S_type 20150905 (not know by domoticz)
    present(alarmChild, S_BINARY, "Alarm display");      // to display alarm text
    present(brightnessChild, S_DIMMER, "Text brightness"); // new S_type 20150905 (not know by domoticz)
    //send(textMsg.set("-"));                            // initialize the V_TEXT at controller for sensor to none (trick for Domoticz)
    request(messageCHILD, V_TEXT, 0);                    // request value from controller
    // Initializations
    requestTime();                            // get the time from controller (handled by receiveTime)
    }

// loop only uses non-blocking functions
void loop() {
    static unsigned long lastUpdate ;                       // Static hold the last update time
    unsigned long now = millis();
    scrollDelay = getScrollDelay();                         // update scroll delay from potentiometer
    readSerial();
    // Check for new conditions & ask for new information from controller every 10 seconds
    if (now-lastUpdate > 10000){
        if (textAlarm){                                     // if alarmstatus: override all text and set max intensity
            strcpy(curMessage, "   ALARM   ");
            mx.control(MD_MAX72XX::INTENSITY, MAX_INTENSITY);   // set current brightness
            mx.control(MD_MAX72XX::SHUTDOWN, false) ;
        } else {                                            // standard (non Alarm actions)
            mx.control(MD_MAX72XX::INTENSITY, textBrightness);  // set current brightness
            mx.control(MD_MAX72XX::SHUTDOWN, textOnOff) ;
            request(messageCHILD, V_TEXT, 0);                // request new value from controller
        }
        lastUpdate = now;
    }
    scrollText();
}
 
// This is called when a new time value was received
void receiveTime(unsigned long controllerTime) {
    Serial.print("Time value received: ");
    Serial.println(controllerTime);
    setTime(controllerTime);                                // time from controller
    timeReceived = true;
    } 

// This is called when a message is received 
void receive(const MyMessage &message) {
    Serial.print("Message: "); Serial.print(message.sensor); Serial.print(", Message: "); Serial.println(message.getString());
    if (message.sensor == messageCHILD){
        if (message.type==V_TEXT) {                     // Text content
        strcpy(newMessage, message.getString());        // copy it in
            newMessageAvailable = true ;
        }
    } else if (message.sensor == alarmChild) {
        if (message.type==V_STATUS) {                   // True/ false content
            textAlarm = message.getBool()?true:false ;  // set alarmflag
            Serial.print("TextAlarm: ");
            Serial.println(textAlarm);
        }
    } else if (message.sensor == brightnessChild){
        if (message.type==V_PERCENTAGE) {               // Level 0..100  content
            textBrightness = map(message.getInt(),0, 100, 0, MAX_INTENSITY ) ;  // map to brightnesslevel 
            Serial.print("TextBrightness: ");
            Serial.println(textBrightness);
        } else if (message.type==V_STATUS) {            // Display on/off
            textOnOff = message.getBool()?false:true ;      // set shutdown/ !on/off
            Serial.print("Text on/off: ");
            Serial.println(textOnOff);
        }
    }
}

    
// Testing purposes: input routine character buffer. Reads serial characters in buffer newMessage.
// sets flag newMessageAvailable to true if completed
void readSerial(void)
{
  static uint8_t    putIndex = 0;

  while (Serial.available())
  {
    newMessage[putIndex] = (char)Serial.read();
    if ((newMessage[putIndex] == '\n') || (putIndex >= BUF_SIZE-3)) // end of message character or full buffer
    {
      // put in a message separator and end the string
      newMessage[putIndex++] = ' ';
      newMessage[putIndex] = '\0';
      // restart the index for next filling spree and flag we have a message waiting
      putIndex = 0;
      newMessageAvailable = true;
    }
    else
      // Just save the next char in next location
      newMessage[putIndex++];
  }
}

[dayve218]

ive spent a couple of hours on this, and i cant get it to work. any help?

[dayve218]

@AWI are you able to help me convrt this to1.6? i cant get it

[hek]

Fixed a couple of thing in the sketch. Now it compiles on 1.6 but you have to install the MD_MAX72xx library which it uses.

[Hoffan]

Where did you put the new sketch??

[hek]

@Hoffan

I updated my post above.

[Hoffan]

Okey... Strange because i test to compile that i Dev Branch and i get this error
Arduino:1.6.5 (Mac OS X), Kort:"Arduino Nano, ATmega328"

Build options changed, rebuilding all
Scrolltext.ino: In function 'void presentation()':
Scrolltext:205: error: too many arguments to function 'void requestTime()'
In file included from /Users/Hoffan/Documents/Arduino-development/libraries/MySensors/MySensor.h:205:0,
from Scrolltext.ino:34:
/Users/Hoffan/Documents/Arduino-development/libraries/MySensors/core/MySensorCore.cpp:234:6: note: declared here
void requestTime() {
^
too many arguments to function 'void requestTime()'

[hek]

Ok, how about now then..

[Hoffan]

Now the compile is working...

Now i will test it in real :)

[Lawrence Helm]

@Hoffan - how did you get on? Interested to know before I order some components :)

[Hoffan]

@Lawrence-Helm

It didn't work all the way for me... And i didn't have the time to check whats wrong

It thing its some thing withe the display settings

[korttoma]

Hi @AWI do you stil have this setup in use? I tried to convert this to 2.0 and hock it up but there is something wrong with the order of the LED elements. They are somehow scrolling in the wrong direction. With part of the code handles this? Might be that I have the wrong library for the MD_MAX72XX where did you get the lib?

[AWI]

Hi @korttoma I have it somewhere in the (large) pile of 'old and/or unfinished' projects :blush:

What I remember is that there are difference between the MAX displays in orientation. Below a picture off mine..

You can change the display type in the MD_MAX72xx.h file of the library.

From line #212 you can choose various display types (only select one). Have fun and let us know your progress..

[korttoma]

Thanks @AWI , the back of my displays are identical to yours and removing the LED element reviles the MAX7219EWG driver underneath.

I will look in to the file you mentioned, maybe I can work something out.

[korttoma]

Chose the FC-16 from the .h file and now it is working! Thanks again @AWI

[A Former User]

@korttoma said:

Chose the FC-16 from the .h file and now it is working! Thanks again @AWI

Thomas, could/would you please share the 2.0 version of the sketch as i also want to use the max7219 modules with mysensors. I already tried them with the md_parola library examples and there are pretty nice animations and effects in there.

Any chances to use those effects other than the scrolling examples with a node red/mqtt gateway combination?

[korttoma]

@Orkspalter said:

please share the 2.0 version of the sketch

Sure I can do that, I will share it when I get home to the computer where it is located.

[A Former User]

@korttoma said:

Sure I can do that, I will share it when I get home to the computer where it is located.

Thanks Tomas

[gus]

Hi,

I'm using this fantastic code as well. This is working on 2.0

Next step for me would be to be able to create an array with more messages, so that the display could cycle thru them.

/*
 PROJECT: MySensors / Scrolling Text display
 PROGRAMMER: AWI
 DATE: september 12, 2015/ last update: september 12, 2015
 FILE: AWI_scroll_MAX.ino
 LICENSE: Public domain

 Hardware: tbd ..Ceech - ATmega328p board w/ NRF24l01
    and MySensors 1.5 ()
        
Special:
    Need to use MySensors development edition 
    
SUMMARY:
    3 S_xx devices for scrolling text
    - Displays a scrolling text from a "V_TEXT" variable
    - additional dimmer sensor for controlling display brightness
    - 'Alarm' switch. If "On", overrides the text display to display ALARM message
    - You can also input messages from the Serial monitor (testing)
    Uses excellent MD_MAX72XX library 
 Remarks:
    Fixed node-id
*/


#include <MD_Parola.h>
#define MY_RADIO_NRF24

// Enable repeater functionality for this node
#define MY_REPEATER_FEATURE



// Use the MD_MAX72XX library to scroll text on the display with the use of the callback function 
// to control what is scrolled on the display text.
// You need to set the used display in the library MD_MAX72XX.h
// User can enter text on the serial monitor and this will display as a
// Speed for the display is controlled by a pot on SPEED_IN analog in.
#include <MD_MAX72xx.h>                     // multipurpose library for MAX72xx diaplay driver  https://parola.codeplex.com/
#include <MySensors.h>                       // Mysensor network
#include <SPI.h>
#include <Time.h>                           //http://playground.arduino.cc/Code/Time
#include <TimeLib.h>
#define USE_POT_CONTROL 0                   // enable Scroll speed  potentiometer
#define PRINT_CALLBACK  1

// Macro to simplify serial print
#define PRINT(s, v) { Serial.print(F(s)); Serial.print(v); }

// Define the number of devices we have in the chain and the hardware interface
// need to be adapted to your setup
const int MAX_DEVICES = 2 ;                 // number of 8x8 displays
const int CLK_PIN = 7 ;                     // SPI like clock
const int DATA_PIN = 8 ;                    // SPI like data
const int CS_PIN = 6 ;                      // SPI like select

// Parola is able to use SPI hardware interface, not testted in combination with MySensors
// MD_MAX72XX mx = MD_MAX72XX(CS_PIN, MAX_DEVICES);
// now use Arbitrary pins
MD_MAX72XX mx = MD_MAX72XX(DATA_PIN, CLK_PIN, CS_PIN, MAX_DEVICES); // instantiate one display chain

// Scrolling parameters, you can attach normal potentiometer to A5, Vcc, Gnd
#if USE_POT_CONTROL
const int SPEED_IN = A5 ;
#else
const int SCROLL_DELAY = 20 ;               // in milliseconds
#endif // USE_POT_CONTROL

const int CHAR_SPACING = 1 ;                // pixels between characters

// MySensors constants & variables
//const byte nodeId = 51 ;                    // MySensors fixed node id
const byte messageCHILD = 8 ;               // Text from ControllerLCD
const byte brightnessChild = 9 ;            // Brightness of display
const byte alarmChild = 10 ;                // Display Alarm text (overrides normal text)
boolean timeReceived = false ;              // Flag to indicate time received
// Display constants & variables
byte textBrightness = 1 ;                   // brightness of display (between 0 - MAX_INTENSITY (0xF)
byte textOnOff = false ;                     // textOnOff = ! shutdown
boolean textAlarm = false ;                 // Alarm (switch S_BINARY)
// Global message buffers shared by MySensors and Scrolling functions
const int BUF_SIZE = 25 ;                   // max payload for MySensors(NRF24l01)
char curMessage[BUF_SIZE];                  // current displayed message
char newMessage[BUF_SIZE];                  // next message to be displayed if available
bool newMessageAvailable = false ;          // new message available flag
uint16_t    scrollDelay;                    // in milliseconds

// *** Definition and initialisation
// define the MySensor network (1.5)
// Initialize messages for sensor network

MyMessage textMsg(messageCHILD, V_TEXT);    // message for Sending Text to Controller


/* MD_MAX72XX functions: can be found in the documentation for the library,
 * no need to customtize callback & scroll routines (unless you want to...)
*/
uint8_t scrollDataSource(uint8_t dev, MD_MAX72XX::transformType_t t)
// Callback function for data that is required for scrolling into the display
{
  static char       *p = curMessage;
  static uint8_t    state = 0;
  static uint8_t    curLen, showLen;
  static uint8_t    cBuf[8];
  uint8_t colData;

  // finite state machine to control what we do on the callback
  switch(state)
  {
    case 0: // Load the next character from the font table
      showLen = mx.getChar(*p++, sizeof(cBuf)/sizeof(cBuf[0]), cBuf);
      curLen = 0;
      state++;

      // if we reached end of message, reset the message pointer
      if (*p == '\0')
      {
        p = curMessage;         // reset the pointer to start of message
        if (newMessageAvailable)    // there is a new message waiting
        {
          strcpy(curMessage, newMessage);   // copy it in
          newMessageAvailable = false;
        }
      }
      // !! deliberately fall through to next state to start displaying

    case 1: // display the next part of the character
      colData = cBuf[curLen++];
      if (curLen == showLen)                // end of character insert interchar space
      {
        showLen = CHAR_SPACING;
        curLen = 0;
        state = 2;
      }
      break;

    case 2: // display inter-character spacing (blank column)
      colData = 0;
      curLen++;
      if (curLen == showLen)
        state = 0;
      break;

    default:
      state = 0;
  }

  return(colData);
}

// Callback (not used here)
void scrollDataSink(uint8_t dev, MD_MAX72XX::transformType_t t, uint8_t col){
// Callback function for data that is being scrolled off the display
#if PRINT_CALLBACK
    Serial.print("\n cb ");
    Serial.print(dev);
    Serial.print(' ');
    Serial.print(t);
    Serial.print(' ');
    Serial.println(col);
#endif
}

// non-blocking text display to be used in loop (call frequently)
void scrollText(void){
    static uint32_t prevTime = 0;
    if (millis()-prevTime >= scrollDelay){                  // Is it time to scroll the text?
        mx.transform(MD_MAX72XX::TSL);                      // scroll along - the callback will load all the data
        prevTime = millis();                                // starting point for next time
        }
    }

// sets the scroll delay (read from potentiometer if enabled)
uint16_t getScrollDelay(void){
#if USE_POT_CONTROL
    uint16_t t = analogRead(SPEED_IN);
    t = map(t, 0, 1023, 25, 250);
    return(t);
#else
    return(SCROLL_DELAY);
#endif
    }

void setup(){
    // set up the display first
    mx.begin();                                             // initialize display chain                 
    mx.setShiftDataInCallback(scrollDataSource);            // define function to get the scrolldata (returned as int8)
    //mx.setShiftDataOutCallback(scrollDataSink);           // not used
    mx.control(MD_MAX72XX::INTENSITY, 0x01);
#if USE_POT_CONTROL                                         // initialize speed potentiometer if enabled
    pinMode(SPEED_IN, INPUT);
#else
    scrollDelay = SCROLL_DELAY;
#endif

    strcpy(curMessage, "I \x03 MySensors ");                // first message on display
    //newMessage[0] = '\0';                                   // new message initialized to empty RE This is not working....
    // Setup MySensors 
   //Serial in Sensor network = 115200
    //Send the sensor node sketch version information to the gateway

} 

void presentation() {

    sendSketchInfo("Scrollo small 52", "1.0");
    present(messageCHILD, S_INFO, "Text line Scroll");   // new S_type 20150905 (not know by domoticz)
    present(alarmChild, S_BINARY, "Alarm display");      // to display alarm text
    present(brightnessChild, S_DIMMER, "Text brightness"); // new S_type 20150905 (not know by domoticz)
    //send(textMsg.set("-"));                            // initialize the V_TEXT at controller for sensor to none (trick for Domoticz)
    request(messageCHILD, V_TEXT, 0);                    // request value from controller
    // Initializations
    requestTime();                            // get the time from controller (handled by receiveTime)
    }

// loop only uses non-blocking functions
void loop() {
    static unsigned long lastUpdate ;                       // Static hold the last update time
    unsigned long now = millis();
    scrollDelay = getScrollDelay();                         // update scroll delay from potentiometer
    //readSerial();
    // Check for new conditions & ask for new information from controller every 10 seconds
    if (now-lastUpdate > 10000){
        if (textAlarm){                                     // if alarmstatus: override all text and set max intensity
            strcpy(curMessage, "   ALARM   ");
            mx.control(MD_MAX72XX::INTENSITY, MAX_INTENSITY);   // set current brightness
            mx.control(MD_MAX72XX::SHUTDOWN, false) ;
        } else {                                            // standard (non Alarm actions)
            mx.control(MD_MAX72XX::INTENSITY, textBrightness);  // set current brightness
            mx.control(MD_MAX72XX::SHUTDOWN, textOnOff) ;
            request(messageCHILD, V_TEXT, 0);                // request new value from controller
        }
        lastUpdate = now;
    }
    scrollText();
}
 
// This is called when a new time value was received
void receiveTime(unsigned long controllerTime) {
    Serial.print("Time value received: ");
    Serial.println(controllerTime);
    setTime(controllerTime);                                // time from controller
    timeReceived = true;
    } 

// This is called when a message is received 
void receive(const MyMessage &message) {
    Serial.print("Message: "); Serial.print(message.sensor); Serial.print(", Message: "); Serial.println(message.getString());
    if (message.sensor == messageCHILD){
        if (message.type==V_TEXT) {                     // Text content
        strcpy(newMessage, message.getString());        // copy it in
            newMessageAvailable = true ;
        }
    } else if (message.sensor == alarmChild) {
        if (message.type==V_STATUS) {                   // True/ false content
            textAlarm = message.getBool()?true:false ;  // set alarmflag
            Serial.print("TextAlarm: ");
            Serial.println(textAlarm);
        }
    } else if (message.sensor == brightnessChild){
        if (message.type==V_PERCENTAGE) {               // Level 0..100  content
            textBrightness = map(message.getInt(),0, 100, 0, MAX_INTENSITY ) ;  // map to brightnesslevel 
            Serial.print("TextBrightness: ");
            Serial.println(textBrightness);
        } else if (message.type==V_STATUS) {            // Display on/off
            textOnOff = message.getBool()?false:true ;      // set shutdown/ !on/off
            Serial.print("Text on/off: ");
            Serial.println(textOnOff);
        }
    }
}

    
// Testing purposes: input routine character buffer. Reads serial characters in buffer newMessage.
// sets flag newMessageAvailable to true if completed
void readSerial(void)
{
  static uint8_t    putIndex = 0;

  while (Serial.available())
  {
    newMessage[putIndex] = (char)Serial.read();
    if ((newMessage[putIndex] == '\n') || (putIndex >= BUF_SIZE-3)) // end of message character or full buffer
    {
      // put in a message separator and end the string
      newMessage[putIndex++] = ' ';
      newMessage[putIndex] = '\0';
      // restart the index for next filling spree and flag we have a message waiting
      putIndex = 0;
      newMessageAvailable = true;
    }
    else
      // Just save the next char in next location
      newMessage[putIndex++];
  }
}