Merge pull request #35 from gbmhunter/develop

Reads no longer clear containers. Local testing improvements.

Author: gbmhunter

.gitignore

@@ -7,4 +7,5 @@ cmake-build-debug/
 docs/_build/
 
 # Build artifacts
-a.out
+a.out
+test/arduino/test

CHANGELOG.md

@@ -5,6 +5,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [v2.7.0] - 2023-02-13
+
+- `Read()` and `ReadBinary()` now append to the provided data containers (string or vector) rather than erase and write.
+- Added `run.sh` bash script for running local serial port tests with connected Arduino Uno (see README). Updated local tests to write and read back data in both string and binary forms.
+
 ## [v2.6.0] - 2023-02-02
 
 - `Read()` and `ReadBinary()` now throw exceptions if they detect that the serial device has been disconnected (thanks to [aldoshkind](https://github.com/aldoshkind) for helping with this one).

README.md

@@ -71,15 +71,19 @@ int main() {
 	// and no flow control
 	SerialPort serialPort("/dev/ttyUSB0", BaudRate::B_57600, NumDataBits::EIGHT, Parity::NONE, NumStopBits::ONE);
 	// Use SerialPort serialPort("/dev/ttyACM0", 13000); instead if you want to provide a custom baud rate
-	serialPort.SetTimeout(-1); // Block when reading until any data is received
+	serialPort.SetTimeout(100); // Block for up to 100ms to receive data
 	serialPort.Open();
 
+	// WARNING: If using the Arduino Uno or similar, you may want to delay here, as opening the serial port causes
+	// the micro to reset!
+
 	// Write some ASCII data
 	serialPort.Write("Hello");
 
-	// Read some data back (will block until at least 1 byte is received due to the SetTimeout(-1) call above)
+	// Read some data back (will block for up to 100ms due to the SetTimeout(100) call above)
 	std::string readData;
 	serialPort.Read(readData);
+	std::cout << "Read data = \"" << readData << "\"" << std::endl;
 
 	// Close the serial port
 	serialPort.Close();
@@ -153,37 +157,42 @@ sudo chmod 666 /dev/ttyACM0
 
 ## Tests
 
+Serial port testing cannot really be done easily on cloud-based CICD platforms, as serial ports and devices connected to these ports are not readibly available (nor configurable). `CppLinuxSerial` relies on running tests manually on your local Linux OS, alongside a connected Arduino Uno configured to echo serial data back (at a later data this could be reconfigured to cycle through tests at different baud rates, parity settings, e.t.c).
+
 ### Prerequisties
 
-Install arduino:avr platform:
+You will need:
+
+* Arduino Uno (or equivalent) dev kit.
+* Linux OS.
+
+Install the arduino-cli as per https://arduino.github.io/arduino-cli/0.21/installation/ on your local Linux machine.
+
+Install the `arduino:avr` platform:
 
 ```
 $ arduino-cli core install arduino:avr
 ```
 
-Detect attached Arduino boards with:
+Make sure Arduino board is detected with:
 
 ```
 $ arduino-cli board list
 ```
 
-Compile:
-
-```
-arduino-cli compile --fqbn arduino:avr:uno Basic/
-```
+### Running
 
-Upload:
+Run the following bash script:
 
 ```
-arduino-cli upload -p /dev/ttyACM0 --fqbn arduino:avr:uno Basic/
+./test/arduino/run.sh 
 ```
 
-### Running
+This script will:
 
-```
-g++ main.cpp -lCppLinuxSerial
-```
+1. Build and install `CppLinuxSerial` onto your local Linux OS.
+1. Build and upload the test Arduino firmware to the connected Arduino Uno (it assumes it's connected to `/dev/ttyACM0`).
+1. Build and run the test C++ application. This sends serial data to the Uno via CppLinuxSerial and expects the data to be echoed back.
 
 ## Changelog
 

include/CppLinuxSerial/SerialPort.hpp

@@ -2,7 +2,7 @@
 /// \file 			SerialPort.hpp
 /// \author 		Geoffrey Hunter <[email protected]> (www.mbedded.ninja)
 /// \created		2014-01-07
-/// \last-modified 	2022-11-12
+/// \last-modified 	2023-02-13
 /// \brief			The main serial port class.
 /// \details
 ///					See README.rst in repo root dir for more info.
@@ -171,20 +171,16 @@ namespace mn {
             /// \throws     CppLinuxSerial::Exception if state != OPEN.
             void WriteBinary(const std::vector<uint8_t>& data);
 
-            /// \brief      Use to read text from the COM port.
-            /// \param      data        The object the read characters from the COM port will be saved to.
-            /// \param      wait_ms     The amount of time to wait for data. Set to 0 for non-blocking mode. Set to -1
-            ///                 to wait indefinitely for new data.
+            /// \brief      Use to read text from the COM port. Blocking nature depends on SetTimeout().
+            /// \param      data        The read characters from the COM port will be appended to this string.
             /// \note       Use ReadBinary() if you want to interpret received data as binary.
             /// \throws     
             ///             CppLinuxSerial::Exception if state != OPEN.
             ///             std::system_error() if device has been disconnected.
             void Read(std::string& data);
 
-            /// \brief      Use to read binary data from the COM port.
-            /// \param      data        The object the read uint8_t bytes from the COM port will be saved to.
-            /// \param      wait_ms     The amount of time to wait for data. Set to 0 for non-blocking mode. Set to -1
-            ///                 to wait indefinitely for new data.
+            /// \brief      Use to read binary data from the COM port. Blocking nature depends on SetTimeout().
+            /// \param      data        The read bytes from the COM port will be appended to this vector.
             /// \note       Use Read() if you want to interpret received data as a string.
             /// \throws     CppLinuxSerial::Exception if state != OPEN.
             ///             std::system_error() if device has been disconnected.

src/SerialPort.cpp

@@ -2,7 +2,7 @@
 //! @file           SerialPort.cpp
 //! @author         Geoffrey Hunter <[email protected]> (www.mbedded.ninja)
 //! @created        2014-01-07
-//! @last-modified  2022-11-11
+//! @last-modified  2023-02-13
 //! @brief          The main serial port class.
 //! @details
 //!             See README.rst in repo root dir for more info.
@@ -517,10 +517,7 @@ namespace CppLinuxSerial {
         }
     }
 
-    void SerialPort::Read(std::string& data)
-    {
-        data.clear();
-
+    void SerialPort::Read(std::string& data) {
         if(fileDesc_ == 0) {
             //this->sp->PrintError(SmartPrint::Ss() << "Read() was called but file descriptor (fileDesc) was 0, indicating file has not been opened.");
             //return false;
@@ -548,16 +545,13 @@ namespace CppLinuxSerial {
             }
         }
         else if(n > 0) {
-            data = std::string(&readBuffer_[0], n);
+            data += std::string(&readBuffer_[0], n);
         }
 
         // If code reaches here, read must of been successful
     }
 
-    void SerialPort::ReadBinary(std::vector<uint8_t>& data)
-    {
-        data.clear();
-
+    void SerialPort::ReadBinary(std::vector<uint8_t>& data) {
         if(fileDesc_ == 0) {
             //this->sp->PrintError(SmartPrint::Ss() << "Read() was called but file descriptor (fileDesc) was 0, indicating file has not been opened.");
             //return false;
@@ -574,18 +568,16 @@ namespace CppLinuxSerial {
         if(n < 0) {
             // Read was unsuccessful
             throw std::system_error(EFAULT, std::system_category());
-        }
-        else if(n == 0) {
+        } else if(n == 0) {
             // n == 0 means EOS, but also returned on device disconnection. We try to get termios2 to distinguish two these two states
             struct termios2 term2;
             int rv = ioctl(fileDesc_, TCGETS2, &term2);
 
             if(rv != 0) {
                 throw std::system_error(EFAULT, std::system_category());
             }
-        }
-        else if(n > 0) {
-            copy(readBuffer_.begin(), readBuffer_.begin() + n, back_inserter(data));
+        } else if(n > 0) {
+            std::copy(readBuffer_.begin(), readBuffer_.begin() + n, back_inserter(data));
         }
 
         // If code reaches here, read must of been successful

test/arduino/Basic/Basic.ino

@@ -13,14 +13,16 @@
 // the setup routine runs once when you press reset:
 void setup() {
   // initialize serial communication at 9600 bits per second:
-  // Serial.begin(9600);
+    Serial.begin(9600);
   // Serial.begin(9600, SERIAL_5N1); // 5 data bits, no parity, 1 stop bit
-  Serial.begin(9600, SERIAL_8E2); // 8 data bits, even parity, 2 stop bits
+  // Serial.begin(9600, SERIAL_8E2); // 8 data bits, even parity, 2 stop bits
 //  Serial.begin(81234); // Used to test custom baud rates
 }
 
 // the loop routine runs over and over again forever:
 void loop() {
-  Serial.println("Hello");
-  delay(100);        // delay in between reads for stability
+    if (Serial.available() > 0) {
+        char c = Serial.read();
+        Serial.print(c);
+    }
 }

test/arduino/main.cpp

@@ -1,40 +1,89 @@
+#include <chrono>
+#include <thread>
+
 #include <CppLinuxSerial/SerialPort.hpp>
 
 using namespace mn::CppLinuxSerial;
 
 // Overload to be able to print vectors to std::cout
 template <typename T>
 std::ostream& operator<<( std::ostream& ostrm, const std::vector<T>& vec ){
+    if (vec.size() == 0) {
+        return ostrm << "[]";
+    }
     for( int j = 0, n = vec.size(); j < n; ++j ){
         ostrm << ",["[ !j ] << " " << vec[ j ];
     }
     return ostrm << " ]";
 }
 
+const double RX_TIMEOUT_MS = 2000;
+
 int main() {
 	// Create serial port object and open serial port
     SerialPort serialPort("/dev/ttyACM0", BaudRate::B_9600, NumDataBits::EIGHT, Parity::NONE, NumStopBits::ONE);
 	// SerialPort serialPort("/dev/ttyACM0", 13000);
-    serialPort.SetTimeout(-1); // Block when reading until any data is received
+
+    // Block for at most 100ms when receiving data
+    // NOTE: I haven't had luck setting this to -1, Read() seems to never return
+    // even though serial data has been sent to Linux
+    serialPort.SetTimeout(100); 
+
+    std::cout << "Opening /dev/ttyACM0 at 9600 baud, 8n1..." << std::flush;
 	serialPort.Open();
+    std::cout << "OK." << std::endl;
 
-	// Write some ASCII datae
-	// serialPort0.Write("Hello");
+    std::cout << "Sleeping to allow Arduino to restart (happens after opening serial port)..." << std::flush;
+    std::this_thread::sleep_for(std::chrono::seconds(3));
+    std::cout << "OK." << std::endl;
 
-	// Read some data back
-    // while(1) {
-    //     std::string readData;
-    //     serialPort.Read(readData);
-    //     std::cout << "Received data: " << readData;
-    // }
+	// Write some ASCII data and read it back
+    std::cout << "Writing string data..." << std::flush;
+    std::string txDataString = "Hello";
+	serialPort.Write(txDataString);
+    std:: cout << "OK." << std::endl;
+	
+    std::cout << "Reading string data..." << std::flush;
+    std::string rxDataString;
+    auto t_start = std::chrono::high_resolution_clock::now();
+    while(1) {
+        serialPort.Read(rxDataString);
+        if (rxDataString == txDataString) {
+            std::cout << "OK." << std::endl;
+            break;
+        }
+        auto t_now = std::chrono::high_resolution_clock::now();
+        double elapsed_time_ms = std::chrono::duration<double, std::milli>(t_now - t_start).count();
+        if (elapsed_time_ms >= RX_TIMEOUT_MS) {
+            std::cout << "ERROR: Did not receive the string data \"Hello\" from Arduino." << std::endl;
+            return -1;
+        }
+    }
 
-	// Read some data back (raw)
+    // Write some binary data and read it back
+    std::cout << "Writing binary data..." << std::flush;
+    std::vector<uint8_t> txDataBinary{ 1, 2, 3, 4, 5 };
+	serialPort.WriteBinary(txDataBinary);
+    std:: cout << "OK." << std::endl;
+	
+    std::cout << "Reading binary data..." << std::flush;
+    std::vector<uint8_t> rxDataBinary;
+    t_start = std::chrono::high_resolution_clock::now();
     while(1) {
-        std::vector<unsigned char> readData;
-        serialPort.ReadBinary(readData);
-        std::cout << "Received data: " << readData;
+        serialPort.ReadBinary(rxDataBinary);
+        if (rxDataBinary == txDataBinary) {
+            std::cout << "OK." << std::endl;
+            break;
+        }
+        auto t_now = std::chrono::high_resolution_clock::now();
+        double elapsed_time_ms = std::chrono::duration<double, std::milli>(t_now - t_start).count();
+        if (elapsed_time_ms >= RX_TIMEOUT_MS) {
+            std::cout << "ERROR: Did not receive the binary data from Arduino." << std::endl;
+            return -1;
+        }
     }
 
 	// Close the serial port
 	serialPort.Close();
+    return 0;
 }

test/arduino/run.sh

@@ -0,0 +1,20 @@
+# exit when any command fails
+set -e
+
+echo "Building/installing CppLinuxSerial..."
+cd build/
+cmake ..
+sudo make install
+
+echo "Building test application..."
+cd ../test/arduino
+g++ main.cpp -lCppLinuxSerial -o test
+
+echo "Compiling Arduino firmware..."
+arduino-cli compile --fqbn arduino:avr:uno ./Basic/
+
+echo "Uploading Arduino firmware..."
+arduino-cli upload -p /dev/ttyACM0 --fqbn arduino:avr:uno ./Basic/
+
+echo "Running test application..."
+./test