Added the Communication Module to the repo.

Communication/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.1.0)
+project(lfr_uart VERSION 0.1.0)
+
+include(CTest)
+enable_testing()
+
+set(THREADS_PREFER_PTHREAD_FLAG ON)
+
+find_package(Threads REQUIRED)
+
+add_executable(lfr_uart uart_communication.cpp)
+
+target_link_libraries( lfr_uart Threads::Threads)
+
+set(CPACK_PROJECT_NAME ${PROJECT_NAME})
+set(CPACK_PROJECT_VERSION ${PROJECT_VERSION})
+include(CPack)

Communication/uart_communication.cpp

@@ -0,0 +1,152 @@
+#include "uart_communication.h"
+
+
+LFR_UART::LFR_UART() : fileDescriptor(-1) {
+    this->openSerialPort();
+    this->configureSerialPort();
+}
+LFR_UART::~LFR_UART() {
+    this->closeSerialPort();
+}
+
+void LFR_UART::openFile(const char *fileName) {
+    this->fileDescriptor = open(fileName, O_RDWR | O_NONBLOCK);
+}
+
+int LFR_UART::writeDataToFile(uint8_t *buff, uint32_t bufferLength) {
+    return write(this->fileDescriptor, buff, bufferLength);
+}
+
+int LFR_UART::readFromFile(uint8_t *buff, uint32_t bufferLength) {
+    return read(this->fileDescriptor, buff, bufferLength);
+}
+
+int LFR_UART::closeFile() {
+    return close(this->fileDescriptor);
+}
+
+uint8_t LFR_UART::doubleToByte(double in){
+    /*
+    * Map the range of -1.0 to 1.0 as double to the range of a byte.
+    * 
+    * -1 -> 0
+    * 0.0 -> 127
+    * 1.0 -> 254
+    * Not using the full range upto 254 to hit the 0.0
+    */
+    double minDouble = -1.0;
+    double maxDouble = 1.0;
+    double rangeDouble = maxDouble - minDouble;
+
+    double minByte = 0.0;
+    double maxByte = 255.0;
+    double rangeByte = maxByte - minByte;
+
+    double progress = in - minDouble;
+    double progressPercent = progress/rangeDouble;
+
+    double inputInByteRange = minByte + progressPercent*rangeByte;
+    return uint8_t(inputInByteRange);
+}
+
+double LFR_UART::byteToDouble(uint8_t in){
+    double minDouble = -1.0;
+    double maxDouble = 1.0;
+    double rangeDouble = maxDouble - minDouble;
+
+    double minByte = 0.0;
+    double maxByte = 255.0;
+    double rangeByte = maxByte - minByte;
+
+    double progress = double(in) - minByte;
+    double progressPercent = progress/rangeByte;
+
+    double inputInDoubleRange = minDouble + progressPercent*rangeDouble;
+    return inputInDoubleRange;
+}
+
+void LFR_UART::sendTelegram(double wheel1, double wheel2, double wheel3, double wheel4){
+    if(wheel1 > 1.0 || wheel2 > 1.0 || wheel3 > 1.0 || wheel4 > 1.0){
+        throw CommunicatorException("Wheel value must not be greater than 1.0");
+    }
+    if(wheel1 < -1.0 || wheel2 < -1.0 || wheel3 < -1.0 || wheel4 < -1.0){
+        throw CommunicatorException("Wheel value must not be smaller than -1.0");
+    }
+
+    uint8_t wheel1B = this->doubleToByte(wheel1);
+    uint8_t wheel2B = this->doubleToByte(wheel2);
+    uint8_t wheel3B = this->doubleToByte(wheel3);
+    uint8_t wheel4B = this->doubleToByte(wheel4);
+
+    uint8_t checksum = wheel1B^wheel2B^wheel3B^wheel4B;
+
+    uint8_t telegram_buffer[5] = {wheel1B, wheel2B, wheel3B, wheel4B, checksum}; 
+    uint32_t telegram_length = 5;
+    this->writeDataToFile(telegram_buffer, telegram_length);
+}
+
+bool LFR_UART::readTelegram(double* buffer){
+    uint8_t tmp_buffer[5] = {0, 0, 0, 0, 0};
+    uint32_t telegram_length = 5;
+    this->readFromFile(tmp_buffer, telegram_length);
+
+    //std::cout << "Read from file: " << std::bitset<8>(tmp_buffer[0]) << ", " << std::bitset<8>(tmp_buffer[1]) << ", " << std::bitset<8>(tmp_buffer[2]) << ", " << std::bitset<8>(tmp_buffer[3]) << ", "  << std::bitset<8>(tmp_buffer[4]) << std::endl;
+
+    if (std::bitset<8>(tmp_buffer[0]^tmp_buffer[1]^tmp_buffer[2]^tmp_buffer[3]) != std::bitset<8>(tmp_buffer[4])){
+        return false;
+    }
+    else {
+        buffer[0] = this->byteToDouble(tmp_buffer[0]);    
+        buffer[1] = this->byteToDouble(tmp_buffer[1]);    
+        buffer[2] = this->byteToDouble(tmp_buffer[2]);    
+        buffer[3] = this->byteToDouble(tmp_buffer[3]);    
+    }
+    return true;
+}
+
+void LFR_UART::openSerialPort() {
+    openFile(this->serialPortPath);
+    if(this->fileDescriptor < 0) {
+        throw CommunicatorException("LFR_UART couldn't open the serial port.");
+        exit(EXIT_FAILURE);
+    }
+}
+
+void LFR_UART::configureSerialPort() {
+    if(tcgetattr(this->fileDescriptor, &this->tty)) {
+        throw CommunicatorException("LFR_UART couldn't get the port attributes.");
+        exit(EXIT_FAILURE);
+    }
+
+    cfsetispeed(&this->tty,B115200);
+    cfsetospeed(&this->tty,B115200);
+
+    cfmakeraw(&this->tty);
+
+    if(tcsetattr(this->fileDescriptor,TCSANOW,&this->tty)) {
+        throw CommunicatorException("LFR_UART couldn't set the port attributes.");
+        exit(EXIT_FAILURE);
+    }
+}
+
+void LFR_UART::closeSerialPort() {
+    this->closeFile();
+}
+
+int main(void) {
+    printf("Starting the loopback application...\r\n");
+    
+    LFR_UART uartCommunicator;
+    uartCommunicator.sendTelegram(-1.0, -0.99, 0.99, 1.0);
+    double buffer[4] = {0.0, 0.0, 0.0, 0.0};
+    sleep(1);
+    if(uartCommunicator.readTelegram(buffer)){
+        for(int i = 0; i < 4; i++) {
+            std::cout << buffer[i] << " ";
+        }
+    }
+    else {
+        std::cout<<"ne";
+    }
+    return 0;
+}

Communication/uart_communication.h

@@ -0,0 +1,56 @@
+#pragma once
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <termios.h>
+#include <iostream>
+#include <exception>
+
+#include <bitset>
+
+
+class LFR_UART
+{
+	int fileDescriptor;
+	const char* serialPortPath = "/dev/ttyS0";
+	
+	void openFile(const char *fileName);
+	int closeFile();
+
+	struct termios tty;
+	
+	void openSerialPort();
+	void configureSerialPort();
+	void closeSerialPort();
+
+	int writeDataToFile(uint8_t *buff, uint32_t bufferLength);
+	int readFromFile(uint8_t *buff, uint32_t bufferLength);
+
+public:
+
+	uint8_t doubleToByte(double in);
+	double byteToDouble(uint8_t in);
+
+	void sendTelegram(double wheel1, double wheel2, double wheel3, double wheel4);
+	bool readTelegram(double* buffer);
+	
+	LFR_UART();
+	~LFR_UART();
+
+};
+
+class CommunicatorException: public std::exception
+{
+	const char* msg;
+public:
+	CommunicatorException(const char* msg): msg(msg) {}
+	virtual const char* what() const throw()
+	{
+		return msg;
+	}
+};