Switch all of the transmit interrupt code to UARTClass. Also, turn USARTClass into a stub because it did nothing differently from the UART code anyway. Now all serial ports use transmit interrupts.

Author: collin80

hardware/arduino/sam/cores/arduino/UARTClass.cpp

@@ -23,9 +23,10 @@
 
 // Constructors ////////////////////////////////////////////////////////////////
 
-UARTClass::UARTClass( Uart* pUart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* pRx_buffer )
+UARTClass::UARTClass( Uart *pUart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer *pRx_buffer, RingBuffer *pTx_buffer )
 {
   _rx_buffer = pRx_buffer ;
+  _tx_buffer = pTx_buffer;
 
   _pUart=pUart ;
   _dwIrq=dwIrq ;
@@ -34,7 +35,14 @@ UARTClass::UARTClass( Uart* pUart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* p
 
 // Public Methods //////////////////////////////////////////////////////////////
 
+
+
 void UARTClass::begin( const uint32_t dwBaudRate )
+{
+	begin( dwBaudRate, UART_MR_PAR_NO | UART_MR_CHMODE_NORMAL );
+}
+
+void UARTClass::begin( const uint32_t dwBaudRate, const uint32_t config )
 {
   // Configure PMC
   pmc_enable_periph_clk( _dwId ) ;
@@ -46,7 +54,7 @@ void UARTClass::begin( const uint32_t dwBaudRate )
   _pUart->UART_CR = UART_CR_RSTRX | UART_CR_RSTTX | UART_CR_RXDIS | UART_CR_TXDIS ;
 
   // Configure mode
-  _pUart->UART_MR = UART_MR_PAR_NO | UART_MR_CHMODE_NORMAL ;
+  _pUart->UART_MR = config ;
 
   // Configure baudrate (asynchronous, no oversampling)
   _pUart->UART_BRGR = (SystemCoreClock / dwBaudRate) >> 4 ;
@@ -58,6 +66,10 @@ void UARTClass::begin( const uint32_t dwBaudRate )
   // Enable UART interrupt in NVIC
   NVIC_EnableIRQ(_dwIrq);
 
+  //make sure both ring buffers are initialized back to empty.
+  _rx_buffer->_iHead = _rx_buffer->_iTail = 0;
+  _tx_buffer->_iHead = _tx_buffer->_iTail = 0;
+
   // Enable receiver and transmitter
   _pUart->UART_CR = UART_CR_RXEN | UART_CR_TXEN ;
 }
@@ -67,6 +79,8 @@ void UARTClass::end( void )
   // clear any received data
   _rx_buffer->_iHead = _rx_buffer->_iTail ;
 
+  while (_tx_buffer->_iHead != _tx_buffer->_iTail); //wait for transmit data to be sent
+
   // Disable UART interrupt in NVIC
   NVIC_DisableIRQ( _dwIrq ) ;
 
@@ -81,6 +95,14 @@ int UARTClass::available( void )
   return (uint32_t)(SERIAL_BUFFER_SIZE + _rx_buffer->_iHead - _rx_buffer->_iTail) % SERIAL_BUFFER_SIZE ;
 }
 
+int UARTClass::availableForWrite(void)
+{
+  int head = _tx_buffer->_iHead;
+  int tail = _tx_buffer->_iTail;
+  if (head >= tail) return SERIAL_BUFFER_SIZE - 1 - head + tail;
+  return tail - head - 1;
+}
+
 int UARTClass::peek( void )
 {
   if ( _rx_buffer->_iHead == _rx_buffer->_iTail )
@@ -109,12 +131,21 @@ void UARTClass::flush( void )
 
 size_t UARTClass::write( const uint8_t uc_data )
 {
-  // Check if the transmitter is ready
-  while ((_pUart->UART_SR & UART_SR_TXRDY) != UART_SR_TXRDY)
-    ;
+  if ((_pUart->UART_SR & UART_SR_TXRDY) != UART_SR_TXRDY) //is the hardware currently busy?
+  {
+	  //if busy we buffer
+	  unsigned int l = (_tx_buffer->_iHead + 1) % SERIAL_BUFFER_SIZE;
+	  while (_tx_buffer->_iTail == l); //spin locks if we're about to overwrite the buffer. This continues once the data is sent
 
-  // Send character
-  _pUart->UART_THR = uc_data;
+	  _tx_buffer->_aucBuffer[_tx_buffer->_iHead] = uc_data;
+	  _tx_buffer->_iHead = l;
+	  _pUart->UART_IER = UART_IER_TXRDY; //make sure TX interrupt is enabled
+  }
+  else 
+  {
+     // Send character
+     _pUart->UART_THR = uc_data ;
+  }
   return 1;
 }
 
@@ -126,6 +157,19 @@ void UARTClass::IrqHandler( void )
   if ((status & UART_SR_RXRDY) == UART_SR_RXRDY)
     _rx_buffer->store_char(_pUart->UART_RHR);
 
+  //Do we need to keep sending data?
+  if ((status & UART_SR_TXRDY) == UART_SR_TXRDY) 
+  {
+	  if (_tx_buffer->_iTail != _tx_buffer->_iHead) { //just in case
+		_pUart->UART_THR = _tx_buffer->_aucBuffer[_tx_buffer->_iTail];
+		_tx_buffer->_iTail = (unsigned int)(_tx_buffer->_iTail + 1) % SERIAL_BUFFER_SIZE;
+	  }
+	  else
+	  {
+		_pUart->UART_IDR = UART_IDR_TXRDY; //mask off transmit interrupt so we don't get it anymore
+	  }
+  }
+
   // Acknowledge errors
   if ((status & UART_SR_OVRE) == UART_SR_OVRE ||
 		  (status & UART_SR_FRAME) == UART_SR_FRAME)

hardware/arduino/sam/cores/arduino/UARTClass.h

@@ -29,18 +29,21 @@ class UARTClass : public HardwareSerial
 {
   protected:
     RingBuffer *_rx_buffer ;
+	RingBuffer *_tx_buffer;
 
   protected:
     Uart* _pUart ;
     IRQn_Type _dwIrq ;
     uint32_t _dwId ;
 
   public:
-    UARTClass( Uart* pUart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* pRx_buffer ) ;
+    UARTClass( Uart* pUart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* pRx_buffer, RingBuffer* pTx_buffer) ;
 
     void begin( const uint32_t dwBaudRate ) ;
+	void begin( const uint32_t dwBaudRate , const uint32_t config ) ;
     void end( void ) ;
     int available( void ) ;
+	int availableForWrite(void);
     int peek( void ) ;
     int read( void ) ;
     void flush( void ) ;

hardware/arduino/sam/cores/arduino/USARTClass.cpp

@@ -23,14 +23,10 @@
 
 // Constructors ////////////////////////////////////////////////////////////////
 
-USARTClass::USARTClass( Usart* pUsart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* pRx_buffer, RingBuffer* pTx_buffer )
+USARTClass::USARTClass( Usart* pUsart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* pRx_buffer, RingBuffer* pTx_buffer ) : UARTClass((Uart*)pUsart, dwIrq, dwId, pRx_buffer, pTx_buffer)
 {
-  _rx_buffer = pRx_buffer;
-  _tx_buffer = pTx_buffer;
 
-  _pUsart=pUsart ;
-  _dwIrq=dwIrq ;
-  _dwId=dwId ;
+  _pUsart=pUsart ; //In case anyone needs USART specific functionality in the future
 }
 
 // Public Methods //////////////////////////////////////////////////////////////
@@ -42,140 +38,26 @@ void USARTClass::begin( const uint32_t dwBaudRate )
 
 void USARTClass::begin( const uint32_t dwBaudRate, const uint32_t config )
 {
-  // Configure PMC
-  pmc_enable_periph_clk( _dwId ) ;
-
-  // Disable PDC channel
-  _pUsart->US_PTCR = US_PTCR_RXTDIS | US_PTCR_TXTDIS ;
-
-  // Reset and disable receiver and transmitter
-  _pUsart->US_CR = US_CR_RSTRX | US_CR_RSTTX | US_CR_RXDIS | US_CR_TXDIS ;
-
-  // Configure mode
-  _pUsart->US_MR = config;
-
-
-  // Configure baudrate, asynchronous no oversampling
-  _pUsart->US_BRGR = (SystemCoreClock / dwBaudRate) / 16 ;
-
-  // Configure interrupts
-  _pUsart->US_IDR = 0xFFFFFFFF;
-  _pUsart->US_IER = US_IER_RXRDY | US_IER_OVRE | US_IER_FRAME;
-
-  // Enable UART interrupt in NVIC
-  NVIC_EnableIRQ( _dwIrq ) ;
-
-  //make sure both ring buffers are initialized back to empty.
-  _rx_buffer->_iHead = _rx_buffer->_iTail = 0;
-  _tx_buffer->_iHead = _tx_buffer->_iTail = 0;
-
-  // Enable receiver and transmitter
-  _pUsart->US_CR = US_CR_RXEN | US_CR_TXEN ;
+	UARTClass::begin(dwBaudRate, config);
 }
 
 void USARTClass::end( void )
 {
-  // clear any received data
-  _rx_buffer->_iHead = _rx_buffer->_iTail ;
-
-  while (_tx_buffer->_iHead != _tx_buffer->_iTail); //wait for transmit data to be sent
-
-  // Disable UART interrupt in NVIC
-  NVIC_DisableIRQ( _dwIrq ) ;
-
-  // Wait for any outstanding data to be sent
-  flush();
-
-  pmc_disable_periph_clk( _dwId ) ;
-}
-
-int USARTClass::available( void )
-{
-  return (uint32_t)(SERIAL_BUFFER_SIZE + _rx_buffer->_iHead - _rx_buffer->_iTail) % SERIAL_BUFFER_SIZE ;
-}
-
-int USARTClass::availableForWrite(void)
-{
-  int head = _tx_buffer->_iHead;
-  int tail = _tx_buffer->_iTail;
-  if (head >= tail) return SERIAL_BUFFER_SIZE - 1 - head + tail;
-  return tail - head - 1;
-}
-
-int USARTClass::peek( void )
-{
-  if ( _rx_buffer->_iHead == _rx_buffer->_iTail )
-    return -1 ;
-
-  return _rx_buffer->_aucBuffer[_rx_buffer->_iTail] ;
-}
-
-int USARTClass::read( void )
-{
-  // if the head isn't ahead of the tail, we don't have any characters
-  if ( _rx_buffer->_iHead == _rx_buffer->_iTail )
-    return -1 ;
-
-  uint8_t uc = _rx_buffer->_aucBuffer[_rx_buffer->_iTail] ;
-  _rx_buffer->_iTail = (unsigned int)(_rx_buffer->_iTail + 1) % SERIAL_BUFFER_SIZE ;
-  return uc ;
+	UARTClass::end();
 }
 
 void USARTClass::flush( void )
 {
-  // Wait for transmission to complete
-  while ((_pUsart->US_CSR & US_CSR_TXRDY) != US_CSR_TXRDY)
-	;
+	UARTClass::flush();
 }
 
 size_t USARTClass::write( const uint8_t uc_data )
 {
-  if ((_pUsart->US_CSR & US_CSR_TXRDY) != US_CSR_TXRDY) //is the hardware currently busy?
-  {
-	  //if busy we buffer
-	  unsigned int l = (_tx_buffer->_iHead + 1) % SERIAL_BUFFER_SIZE;
-	  while (_tx_buffer->_iTail == l); //spin locks if we're about to overwrite the buffer. This continues once the data is sent
-
-	  _tx_buffer->_aucBuffer[_tx_buffer->_iHead] = uc_data;
-	  _tx_buffer->_iHead = l;
-	  _pUsart->US_IER = US_IER_TXRDY; //make sure TX interrupt is enabled
-  }
-  else 
-  {
-     // Send character
-     _pUsart->US_THR = uc_data ;
-  }
-  return 1;
+	return UARTClass::write(uc_data);
 }
 
 void USARTClass::IrqHandler( void )
 {
-  uint32_t status = _pUsart->US_CSR;
-
-  // Did we receive data ?
-  if ((status & US_CSR_RXRDY) == US_CSR_RXRDY) 
-  {
-	_rx_buffer->store_char(_pUsart->US_RHR);
-  }
-  //Do we need to keep sending data?
-  if ((status & US_CSR_TXRDY) == US_CSR_TXRDY) 
-  {
-	  if (_tx_buffer->_iTail != _tx_buffer->_iHead) { //just in case
-		_pUsart->US_THR = _tx_buffer->_aucBuffer[_tx_buffer->_iTail];
-		_tx_buffer->_iTail = (unsigned int)(_tx_buffer->_iTail + 1) % SERIAL_BUFFER_SIZE;
-	  }
-	  else
-	  {
-		_pUsart->US_IDR = US_IDR_TXRDY; //mask off transmit interrupt so we don't get it anymore
-	  }
-  }
-
-  // Acknowledge errors
-  if ((status & US_CSR_OVRE) == US_CSR_OVRE ||
-		  (status & US_CSR_FRAME) == US_CSR_FRAME)
-  {
-	// TODO: error reporting outside ISR
-    _pUsart->US_CR |= US_CR_RSTSTA;
-  }
+	UARTClass::IrqHandler();
 }
 

hardware/arduino/sam/cores/arduino/USARTClass.h

@@ -19,7 +19,7 @@
 #ifndef _USART_CLASS_
 #define _USART_CLASS_
 
-#include "HardwareSerial.h"
+#include "UARTClass.h"
 #include "RingBuffer.h"
 
 // Includes Atmel CMSIS
@@ -56,27 +56,17 @@
 #define SERIAL_7O2 (US_MR_USART_MODE_NORMAL | US_MR_USCLKS_MCK | US_MR_CHRL_7_BIT | US_MR_PAR_ODD | US_MR_NBSTOP_2_BIT | US_MR_CHMODE_NORMAL)
 #define SERIAL_8O2 (US_MR_USART_MODE_NORMAL | US_MR_USCLKS_MCK | US_MR_CHRL_8_BIT | US_MR_PAR_ODD | US_MR_NBSTOP_2_BIT | US_MR_CHMODE_NORMAL)
 
-class USARTClass : public HardwareSerial
+class USARTClass : public UARTClass
 {
-  protected:
-    RingBuffer *_rx_buffer;
-	RingBuffer *_tx_buffer;
-
   protected:
     Usart* _pUsart ;
-    IRQn_Type _dwIrq ;
-    uint32_t _dwId ;
 
   public:
     USARTClass( Usart* pUsart, IRQn_Type dwIrq, uint32_t dwId, RingBuffer* pRx_buffer, RingBuffer* pTx_buffer ) ;
 
     void begin( const uint32_t dwBaudRate ) ;
     void begin( const uint32_t dwBaudRate , const uint32_t config ) ;
     void end( void ) ;
-    int available( void ) ;
-	int availableForWrite(void);
-    int peek( void ) ;
-    int read( void ) ;
     void flush( void ) ;
     size_t write( const uint8_t c ) ;
 

hardware/arduino/sam/variants/arduino_due_x/variant.cpp

@@ -299,8 +299,9 @@ extern const PinDescription g_APinDescription[]=
  * UART objects
  */
 RingBuffer rx_buffer1;
+RingBuffer tx_buffer1;
 
-UARTClass Serial(UART, UART_IRQn, ID_UART, &rx_buffer1);
+UARTClass Serial(UART, UART_IRQn, ID_UART, &rx_buffer1, &tx_buffer1);
 void serialEvent() __attribute__((weak));
 void serialEvent() { }