Spitting incoming serial data arduino and visual basic

Hello! as you can probably tell, my last post was written in a fury of incoherency, but I needed to get the code out there so it is what it is.

The main focus of this post is to showcase the arduino program. The visual basic in the video is very simple, and there will be much more on that later.

This below program will take a string of characters fed to the arduino and split them into¬†usable¬†parts. This is a very valuable tool for working with serial and arduino. It’s pretty well commented, but if you have any questions, PLEASE leave a comment. I’d love to see some conversation here.

const char EOPmarker = '.'; //This is the end of packet marker
char serialbuf[32]; //This gives the incoming serial some room. Change it if you want a longer incoming.

#include <string.h> // we'll need this for subString
#define MAX_STRING_LEN 20 // like 3 lines above, change as needed.

#include <LiquidCrystal.h> //we'll need this for the lcd
LiquidCrystal lcd(7, 8, 9, 10, 11, 12); //pins for the lcd, I set it up using the ladyada tutorial.

void setup(){
 lcd.begin(16, 2);
 Serial.begin(9600); //changing this to other speeds has not been tested using this meathod
}

void loop() {
 if (Serial.available() > 0) { //makes sure something is ready to be read
 lcd.clear(); //clears for incoming stuff, won't clear if there isin't data to be read
 static int bufpos = 0; //starts the buffer back at the first position in the incoming serial.read
 char inchar = Serial.read(); //assigns one byte (as serial.read()'s only input one byte at a time
 if (inchar != EOPmarker) { //if the incoming character is not the byte that is the incoming package ender
 serialbuf[bufpos] = inchar; //the buffer position in the array get assigned to the current read
 bufpos++; //once that has happend the buffer advances, doing this over and over again until the end of package marker is read.
 }
 else { //once the end of package marker has been read
 serialbuf[bufpos] = 0; //restart the buff
 bufpos = 0; //restart the position of the buff
 lcd.write(subStr(serialbuf, ",", 1)); //witres the first bit of content before the first comma (or other seperator) to the lcd. You could also do math or anything else with these. You could use atoi to change them to integers.
 lcd.write("|separator|"); //this signifies that the first seperation has occured
 lcd.write(subStr(serialbuf, ",", 2)); //same thing as 2 lines above, but with the second parts. this can be repeated
 }
 }
}

// below is just function logic, which I do not fully understand. but it works.
char* subStr (char* input_string, char *separator, int segment_number) {
 char *act, *sub, *ptr;
 static char copy[MAX_STRING_LEN];
 int i;

strcpy(copy, input_string);

for (i = 1, act = copy; i <= segment_number; i++, act = NULL) {

sub = strtok_r(act, separator, &ptr);
 if (sub == NULL) break;
 }
 return sub;
}

//www.esologic.com
//Thanks to http://arduino.cc/forum/index.php?topic=119429

So for example if you inputted

123,456.

it would output

123|separator|456

to the lcd, or the serial monitor if you tweaked the code.

Now for the code in the video. The only different part about this is that it writes the two values to the servos.

</pre>
const char EOPmarker = '.'; //This is the end of packet marker
char serialbuf[32]; //This gives the incoming serial some room. Change it if you want a longer incoming.

#include <string.h> // we'll need this for subString
#define MAX_STRING_LEN 20 // like 3 lines above, change as needed.

#include <LiquidCrystal.h> //we'll need this for the lcd
LiquidCrystal lcd(7, 8, 9, 10, 11, 12); //pins for the lcd, I set it up using the ladyada tutorial.

#include <Servo.h>
Servo left_servo;
Servo right_servo;

int left_servo_pos;
int right_servo_pos;
void setup(){
 lcd.begin(16, 2);
 left_servo.attach(2);
 right_servo.attach(3);
 Serial.begin(9600); //changing this to other speeds has not been tested using this meathod
}

void loop() {
 if (Serial.available() > 0) { //makes sure something is ready to be read
 lcd.clear(); //clears for incoming stuff, won't clear if there isin't data to be read
 static int bufpos = 0; //starts the buffer back at the first position in the incoming serial.read
 char inchar = Serial.read(); //assigns one byte (as serial.read()'s only input one byte at a time
 if (inchar != EOPmarker) { //if the incoming character is not the byte that is the incoming package ender
 serialbuf[bufpos] = inchar; //the buffer position in the array get assigned to the current read
 bufpos++; //once that has happend the buffer advances, doing this over and over again until the end of package marker is read.
 }
 else { //once the end of package marker has been read
 serialbuf[bufpos] = 0; //restart the buff
 bufpos = 0; //restart the position of the buff

 left_servo_pos = atoi(subStr(serialbuf, ",", 1));
 lcd.write("Left Servo:");
 lcd.write(subStr(serialbuf, ",", 1)); //witres the first bit of content before the first comma (or other seperator) to the lcd
 left_servo.write(left_servo_pos);

 lcd.setCursor(0, 1);

 right_servo_pos = atoi(subStr(serialbuf, ",", 2));
 lcd.write("Right Servo:"); //this signifies that the first seperation has occured
 lcd.write(subStr(serialbuf, ",", 2)); //same thing as 2 lines above, but with the second parts. this can be repeated
 right_servo.write(right_servo_pos);
 }
 }
}

// below is just function logic, which I do not fully understand. but it works.
char* subStr (char* input_string, char *separator, int segment_number) {
 char *act, *sub, *ptr;
 static char copy[MAX_STRING_LEN];
 int i;

 strcpy(copy, input_string);

for (i = 1, act = copy; i <= segment_number; i++, act = NULL) {

 sub = strtok_r(act, separator, &ptr);
 if (sub == NULL) break;
 }
 return sub;
}

//www.esologic.com
//Thanks to http://arduino.cc/forum/index.php?topic=119429

One comment

  1. cctv camera says:

    Truly good site thank you so much for your time in writing the posts for all of us to learn about.

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