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@fairchild
Created April 13, 2009 07:37
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Simple updated examples of arduino serial communications
/* ------------------------------------------------
* SERIAL COM - HANDELING MULTIPLE BYTES inside ARDUINO - 01_simple version
* by beltran berrocal
*
* this prog establishes a connection with the pc and waits for it to send him
* a long string of characters like "hello Arduino!".
* Then Arduino informs the pc that it heard the whole sentence
*
* this is the first step for establishing sentence long conversations between arduino and the pc.
* serialRead() reads one byte at a time from the serial buffer.
* so in order to print out the whole sentence at once
* (it is actually still printing one byte at a time but the pc will receive it
* not interupted by newLines or other printString inside you loop)
* You must loop untill there are bytes in the serial buffer and
* and print right away that byte you just read.
* after that the loop can continue it's tasks.
*
* created 15 Decembre 2005;
* copyleft 2005 Progetto25zero1 <http://www.progetto25zero1.com>
*
* --------------------------------------------------- */
int serIn; //var that will hold the bytes in read from the serialBuffer
void setup() {
Serial.begin(9600);
}
//auto go_to_the_line function
//void printNewLine() {
// Serial.print(13, BYTE);
// Serial.print(10, BYTE);
//}
void loop () {
//simple feedback from Arduino Serial.println("Hello World");
// only if there are bytes in the serial buffer execute the following code
if(Serial.available()) {
//inform that Arduino heard you saying something
Serial.print("Arduino heard you say: ");
//keep reading and printing from serial untill there are bytes in the serial buffer
while (Serial.available()>0){
serIn = Serial.read(); //read Serial
Serial.print(serIn, BYTE); //prints the character just read
}
//the serial buffer is over just go to the line (or pass your favorite stop char)
Serial.println();
}
//slows down the visualization in the terminal
delay(1000);
}
/* ------------------------------------------------
* SERIAL COM - HANDELING MULTIPLE BYTES inside ARDUINO - 01_simple version
* by beltran berrocal
*
* this prog establishes a connection with the pc and waits for it to send him
* a long string of characters like "hello Arduino!".
* Then Arduino informs the pc that it heard the whole sentence
*
* this is the first step for establishing sentence long conversations between arduino and the pc.
* serialRead() reads one byte at a time from the serial buffer.
* so in order to print out the whole sentence at once
* (it is actually still printing one byte at a time but the pc will receive it
* not interupted by newLines or other printString inside you loop)
* You must loop untill there are bytes in the serial buffer and
* and print right away that byte you just read.
* after that the loop can continue it's tasks.
*
* created 15 Decembre 2005;
* copyleft 2005 Progetto25zero1 <http://www.progetto25zero1.com>
*
* --------------------------------------------------- */
int serIn; //var that will hold the bytes in read from the serialBuffer
void setup() {
Serial.begin(9600);
}
//auto go_to_the_line function
//void printNewLine() {
// Serial.print(13, BYTE);
// Serial.print(10, BYTE);
//}
void loop () {
//simple feedback from Arduino Serial.println("Hello World");
// only if there are bytes in the serial buffer execute the following code
if(Serial.available()) {
//inform that Arduino heard you saying something
Serial.print("Arduino heard you say: ");
//keep reading and printing from serial untill there are bytes in the serial buffer
while (Serial.available()>0){
serIn = Serial.read(); //read Serial
Serial.print(serIn, BYTE); //prints the character just read
}
//the serial buffer is over just go to the line (or pass your favorite stop char)
Serial.println();
}
//slows down the visualization in the terminal
delay(1000);
}
/* ------------------------------------------------
* SERIAL COM - HANDELING MULTIPLE BYTES inside ARDUINO - 03_function development
* by beltran berrocal
*
* this prog establishes a connection with the pc and waits for it to send him
* a long string of characters like "hello Arduino!".
* Then Arduino informs the pc that it heard the whole sentence
*
* the same as examlpe 02 but it deploys 2 reusable functions.
* for doing the same job.
* readSerialString() and printSerialString()
* the only problem is that they use global variables instead of getting them passed
* as parameters. this means that in order to reuse this code you should also copy
* the 4 variables instantiated at the beginning of the code.
* Another problem is that if you expect more than one string at a time
* you will have to duplicate and change names to all variables as well as the functions.
* Next version should have the possibility to pass the array as a parameter to the function.
*
* created 15 Decembre 2005;
* copyleft 2005 Progetto25zero1 <http://www.progetto25zero1.com>
*
* --------------------------------------------------- */
int serIn; // var that will hold the bytes-in read from the serialBuffer
char serInString[100]; // array that will hold the different bytes 100=100characters;
// -> you must state how long the array will be else it won't work.
int serInIndx = 0; // index of serInString[] in which to insert the next incoming byte
int serOutIndx = 0; // index of the outgoing serInString[] array;
/*read a string from the serial and store it in an array
//you must supply the array variable and the index count
void readSerialString (char *strArray, int indx) {
int sb; //declare local serial byte before anything else
Serial.print("reading Serial String: ");
if(serialAvailable()) {
while (serialAvailable()){
sb = serialRead();
strArray[indx] = sb;
indx++;
serialWrite(sb);
}
}
Serial.println();
}
*/
//read a string from the serial and store it in an array
//this func uses globally set variable so it's not so reusable
//I need to find the right syntax to be able to pass to the function 2 parameters:
// the stringArray and (eventually) the index count
void readSerialString () {
int sb;
if(Serial.available()) {
//Serial.print("reading Serial String: "); //optional confirmation
while (Serial.available()){
sb = Serial.read();
serInString[serInIndx] = sb;
serInIndx++;
//serialWrite(sb); //optional confirmation
}
//Serial.println();
}
}
//print the string all in one time
//this func as well uses global variables
void printSerialString() {
if( serInIndx > 0) {
Serial.print("Arduino memorized that you said: ");
//loop through all bytes in the array and print them out
for(serOutIndx=0; serOutIndx < serInIndx; serOutIndx++) {
Serial.print( serInString[serOutIndx] ); //print out the byte at the specified index
//serInString[serOutIndx] = ""; //optional: flush out the content
}
//reset all the functions to be able to fill the string back with content
serOutIndx = 0;
serInIndx = 0;
Serial.println();
}
}
void setup() {
Serial.begin(9600);
Serial.println("Hello World");
}
void loop () {
//simple feedback from Arduino
//read the serial port and create a string out of what you read
//readSerialString(serInString, serInIndx);
readSerialString();
//do somenthing else perhaps wait for other data or read another Serial string
Serial.println ("------------ arduino is doing somenthing else ");
//try to print out collected information. it will do it only if there actually is some info.
printSerialString();
//slows down the visualization in the terminal
delay(2000);
}
@ipatch
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ipatch commented May 3, 2013

nice write up man.

@Allday3D
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The 'BYTE' keyword is no longer supported!

@Satnam00
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Satnam00 commented Jun 7, 2018

What if we wand to send integers like 465 through uart Definitely We have to send 4,6,5 but how to what functiion is over here which can hepl us. Or we have to create our own function. Please answer .

@burton-robotics
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Can anyone help me I am using a laser model tw10sp to do distance measurement so in the protocol it has me send the following
Description Address Code Function Code Starting Address Register Number CRC
Send: 0x01 0x03 0x00 0x0F 0x00 0x02 0xF4 0x08 and the normal response example is :
Description Address Code Function Code Bytes Register 1 Value Register 2 Value CRC
Normal response: 0x01 0x03 0x04 0x00 0x00 0xE0 0xA1 0x72 0x4B
Note (the distance in this instruction is 4 bytes, 0x00 0x00 0xE0 0xA1, and the distance is 0x0000E0A1, converted to 57505mm in decimal)
I am using a micro on Serial1 so what i did just to get the reading back was:

void setup() {
Serial.begin(38400);
Serial1.begin(38400);
}
void loop () {
Serial1.write (0x01);
Serial1.write (0x03);
Serial1.write (0x00);
Serial1.write (0x0F);
Serial1.write (0x00);
Serial1.write (0x02);
Serial1.write (0x0F);
Serial1.write (0x08);

if (Serial1.available())
{
Serial.print(Serial1.read(),HEX);
}

This is just a simple pass through code and but what i need is to take the 4 bytes for the distance and convert them to a decimal number.
Can someone point me in the right direction

@medbhmeca
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hello burton-robotics, did you find a solution to receive mesurement from the tw10sp laser sensor ?

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