SoftwareSerial

Projects Programming
1

I am using the SoftwareSerial library with a 4d systems 4.3" screen

I have tried this on both the Arduino UNO and the Arduino Mega 2560 with the same result.

I have used the Visi Genie to create all of my interfaces.

The problem lies in the fact that I am getting 0 data transfer from the screen to arduino

mySerial.available() is giving me 0 which will not allow any of the other code to run.

I have also used the following code.

/// 
/// @mainpage	Arduino_RGB_Genie
/// @details	Set colour from panel with red-green-blue sliders
/// @n
/// @n @a	Developed with [embedXcode](http://embedXcode.weebly.com)
///
/// @author	Rei Vilo
/// @date	Nov 13, 2012
/// @version	308
///

// Core library
#include "Arduino.h" // for Arduino 1.0

// Include application, user and local libraries
#include "SoftwareSerial.h"

// Define variables and constants
SoftwareSerial mySerial(2, 3);

#define RED_PIN		 9
#define GREEN_PIN	10
#define BLUE_PIN	11

#define READ_OBJ		0x00
#define WRITE_OBJ		0x01
#define REPORT_OBJ		0x05
#define REPORT_EVENT	0x07

const uint16_t buttonReset	= 0x0600; 
const uint16_t sliderRed	= 0x0400;
const uint16_t sliderGreen	= 0x0401;
const uint16_t sliderBlue	= 0x0402;

uint8_t red, green, blue;
uint8_t command;
uint16_t object, value;
boolean flag;

uint8_t nacAck() {
	delay(10);
	while (!mySerial.available());
	return mySerial.read(); // 0x06 or 0xd5
}

bool readMessage(uint8_t &command0, uint16_t &object0, uint16_t &value0) {
	bool flag0 = false;
	uint8_t buffer[6];
	uint8_t checksum = 0x00;
	uint8_t i=0;

	if (mySerial.available()>0) {
		buffer[i] = mySerial.read();
		command0 = buffer[0];
		i++;
		checksum = command0;

		if (command0==REPORT_EVENT) {
			if (mySerial.available()>3) {
				buffer[i] = mySerial.read();
				checksum ^= buffer[i];
				i++;
				buffer[i] = mySerial.read();
				checksum ^= buffer[i];
				i++;
				object0 = buffer[1]<<8 | buffer[2];

				buffer[i] = mySerial.read();
				checksum ^= buffer[i];
				i++;
				object0 = buffer[1]<<8 | buffer[2];
				buffer[i] = mySerial.read();
				checksum ^= buffer[i];
				i++;
				value0 = buffer[3]<<8 | buffer[4];
			}				
		}
		flag0 = (checksum==mySerial.read());
	}
	return flag0;
}


bool sendMessage(uint8_t command0, uint16_t object0, uint16_t value0) {
	bool flag0 = false;
	uint8_t buffer[6];
	uint8_t checksum = 0x00;
	uint8_t i=0;

	buffer[i] = command0;
	checksum = command0;
	i++;

	buffer[i] = object0 >>8;
	checksum ^= buffer[i];
	i++;

	buffer[i] = object0 & 0xff;
	checksum ^= buffer[i];
	i++;

	buffer[i] = value0 >>8;
	checksum ^= buffer[i];
	i++;

	buffer[i] = value0 & 0xff;
	checksum ^= buffer[i];
	i++;

	buffer[i] = checksum;
	i++;

	mySerial.write(buffer, i);

	return (nacAck()==0x06);
}

void update() {
	analogWrite(RED_PIN, red);             // value for red channel
	analogWrite(GREEN_PIN, green);             // value for blue channel
	analogWrite(BLUE_PIN, blue);             // value for green channel
}


void reset() {
	uint8_t a;

	red   = 0x7f;
	green = 0x7f;
	blue  = 0x7f;

	mySerial.flush();
	a = sendMessage(WRITE_OBJ, sliderRed, red);
	a = sendMessage(WRITE_OBJ, sliderGreen, green);
	a = sendMessage(WRITE_OBJ, sliderBlue, blue);

	update();
}


// Add setup code
void setup() {
	delay(3000);
	mySerial.begin(9600);

	pinMode(RED_PIN, OUTPUT);
	pinMode(GREEN_PIN, OUTPUT);
	pinMode(BLUE_PIN, OUTPUT);

	reset();
	update();
}

// Add loop code
void loop() {
	if (readMessage(command, object, value)) {
		if (command==0x07) {
			switch (object) {
			case buttonReset:
				reset();
				break;

			case sliderRed:
				red = value & 0xff;
				update();
				break;

			case sliderGreen:
				green = value & 0xff;
				update();
				break;

			case sliderBlue:
				blue = value & 0xff;
				update();
				break;

			default:
				break;
			}
		}
	}
	delay(100);
}

Any ideas???

2

I have also used both the shield that came with it and bypassed the shield with hardwires so I could make sure TX and RX pins were correct with the same results

3

Are you saying, mySerial.available() is always zero ?

That means, you are not receiving anything. Most likely causes are
(a) incorrect connection
(b) the sending device is not sending anything !

Suggestion. Connect to something else, the PC serial monitor, some other serial device, and see if you
receive anything from this mySerial connection.

Suggestion. Try some different pins for the mySerial connection.

Suggestion. Swap the TX and RX connections. It is supposed to be TX -> RX and RX <- TX but some devices are
incorrectly labelled.

Your other problem is likely to be, even when you get something there on Serial.available(), your logic
in that reading function looks bad, it is unlikely to work reliably, it does not adequately account for
the asynchronicity of the serial communications.

4

I used the liberary and it is working fine.

SoftwareSerial.rar (8.16 KB)