Use Arduino_Threads for Threadsafe_Serial_ProtocolWrapping.

Author: aentinger

examples/Threadsafe_IO/Threadsafe_Serial_ProtocolWrapping/GPS_Thread.inot

@@ -0,0 +1,64 @@
+/**************************************************************************************
+ * FUNCTION DEFINITION
+ **************************************************************************************/
+
+static String nmea_message_prefix(String const & /* msg */)
+{
+  return String("$");
+}
+
+static String nmea_message_suffix(String const & prefix, String const & msg)
+{
+  /* NMEA checksum is calculated over the complete message
+   * starting with '$' and ending with the end of the message.
+   */
+  byte checksum = 0;
+  std::for_each(msg.c_str(),
+                msg.c_str() + msg.length(),
+                [&checksum](char const c)
+                {
+                  checksum ^= static_cast<uint8_t>(c);
+                });
+  /* Assemble the footer of the NMEA message. */
+  char footer[16] = {0};
+  snprintf(footer, sizeof(footer), "*%02X\r\n", checksum);
+  return String(footer);
+}
+
+/**************************************************************************************
+ * SETUP/LOOP
+ **************************************************************************************/
+
+void setup()
+{
+  Serial.begin(9600);
+
+  Serial.prefix(nmea_message_prefix);
+  Serial.suffix(nmea_message_suffix);
+}
+
+void loop()
+{
+  /* Sleep between 5 and 500 ms */
+  rtos::ThisThread::sleep_for(rtos::Kernel::Clock::duration_u32(random(5,500)));
+
+  /* Print a fake NMEA GPRMC message:
+   * $GPRMC,062101.714,A,5001.869,N,01912.114,E,955535.7,116.2,290520,000.0,W*45\r\n
+   */
+  Serial.block();
+
+  Serial.print("GPRMC,");
+  Serial.print(millis());
+  Serial.print(",A,");
+  Serial.print("5001.869,");
+  Serial.print("N,");
+  Serial.print("01912.114,");
+  Serial.print("E,");
+  Serial.print("955535.7,");
+  Serial.print("116.2,");
+  Serial.print("290520,");
+  Serial.print("000.0,");
+  Serial.print("W");
+
+  Serial.unblock();
+}

examples/Threadsafe_IO/Threadsafe_Serial_ProtocolWrapping/SharedVariables.h

@@ -4,107 +4,23 @@
 
 #include <Arduino_Threads.h>
 
-/**************************************************************************************
- * CONSTANTS
- **************************************************************************************/
-
-static size_t constexpr NUM_THREADS = 5;
-
-/**************************************************************************************
- * FUNCTION DECLARATION
- **************************************************************************************/
-
-void serial_thread_func();
-
-/**************************************************************************************
- * GLOBAL VARIABLES
- **************************************************************************************/
-
-static char thread_name[NUM_THREADS][32];
-#undef Serial
-#ifdef ARDUINO_PORTENTA_H7_M4
-  SerialDispatcher Serial(Serial1); /* No SerialUSB for Portenta H7 / M4 Core */
-#else
-  SerialDispatcher Serial(SerialUSB);
-#endif
-
 /**************************************************************************************
  * SETUP/LOOP
  **************************************************************************************/
 
 void setup()
 {
-  /* Fire up some threads all accessing the LSM6DSOX */
-  for(size_t i = 0; i < NUM_THREADS; i++)
-  {
-    snprintf(thread_name[i], sizeof(thread_name[i]), "Thread #%02d", i);
-    rtos::Thread * t = new rtos::Thread(osPriorityNormal, OS_STACK_SIZE, nullptr, thread_name[i]);
-    t->start(serial_thread_func);
-  }
-}
-
-void loop()
-{
-
-}
-
-/**************************************************************************************
- * FUNCTION DEFINITION
- **************************************************************************************/
+  Serial.begin(9600);
+  while (!Serial) { }
 
-String nmea_message_prefix(String const & /* msg */)
-{
-  return String("$");
+  GPS_Thread.start();
 }
 
-String nmea_message_suffix(String const & prefix, String const & msg)
+void loop()
 {
-  /* NMEA checksum is calculated over the complete message
-   * starting with '$' and ending with the end of the message.
+  /* If we don't hand back control then the main thread
+   * will hog the CPU and all other thread's won't get
+   * time to be executed.
    */
-  byte checksum = 0;
-  std::for_each(msg.c_str(),
-                msg.c_str() + msg.length(),
-                [&checksum](char const c)
-                {
-                  checksum ^= static_cast<uint8_t>(c);
-                });
-  /* Assemble the footer of the NMEA message. */
-  char footer[16] = {0};
-  snprintf(footer, sizeof(footer), "*%02X\r\n", checksum);
-  return String(footer);
-}
-
-void serial_thread_func()
-{
-  Serial.begin(9600);
-
-  Serial.prefix(nmea_message_prefix);
-  Serial.suffix(nmea_message_suffix);
-
-  for(;;)
-  {
-    /* Sleep between 5 and 500 ms */
-    rtos::ThisThread::sleep_for(rtos::Kernel::Clock::duration_u32(random(5,500)));
-
-    /* Print a fake NMEA GPRMC message:
-     * $GPRMC,062101.714,A,5001.869,N,01912.114,E,955535.7,116.2,290520,000.0,W*45\r\n
-     */
-    Serial.block();
-
-    Serial.print("GPRMC,");
-    Serial.print(millis());
-    Serial.print(",A,");
-    Serial.print("5001.869,");
-    Serial.print("N,");
-    Serial.print("01912.114,");
-    Serial.print("E,");
-    Serial.print("955535.7,");
-    Serial.print("116.2,");
-    Serial.print("290520,");
-    Serial.print("000.0,");
-    Serial.print("W");
-
-    Serial.unblock();
-  }
+  rtos::ThisThread::yield();
 }