Shrink oversized objects in SRAM

824 bytes is gained for use by sketches. Two new defines are added;
CDCACM_BUFFER_SIZE and UART_BUFFER_SIZE. The CDC-ACM Serial class and
the UART driver had been using the same #define for buffer size--
SERIAL_BUFFER_SIZE-- and separating them means that the CDC-ACM buffer
can stay the same size, while the UART buffer is shrunk.

Author: eriknyquist

cores/arduino/CDCSerialClass.cpp

@@ -83,7 +83,7 @@ void CDCSerialClass::end( void )
 
 int CDCSerialClass::available( void )
 {
-#define SBS	SERIAL_BUFFER_SIZE
+#define SBS	CDCACM_BUFFER_SIZE
 
   if (!_shared_data->device_open)
     return (0);
@@ -100,7 +100,7 @@ int CDCSerialClass::availableForWrite(void)
     int tail = _tx_buffer->tail;
 
     if (head >= tail)
-        return SERIAL_BUFFER_SIZE - head + tail - 1;
+        return CDCACM_BUFFER_SIZE - head + tail - 1;
     return tail - head - 1;
 }
 
@@ -118,7 +118,7 @@ int CDCSerialClass::read( void )
     return -1;
 
   uint8_t uc = _rx_buffer->data[_rx_buffer->tail];
-  _rx_buffer->tail = (_rx_buffer->tail + 1) % SERIAL_BUFFER_SIZE;
+  _rx_buffer->tail = (_rx_buffer->tail + 1) % CDCACM_BUFFER_SIZE;
   return uc;
 }
 
@@ -138,7 +138,7 @@ size_t CDCSerialClass::write( const uint8_t uc_data )
         return(0);
 
     do {
-        int i = (uint32_t)(_tx_buffer->head + 1) % SERIAL_BUFFER_SIZE;
+        int i = (uint32_t)(_tx_buffer->head + 1) % CDCACM_BUFFER_SIZE;
         // if we should be storing the received character into the location
         // just before the tail (meaning that the head would advance to the
         // current location of the tail), we're about to overflow the buffer

cores/arduino/RingBuffer.cpp

@@ -23,14 +23,14 @@
 
 RingBuffer::RingBuffer( void )
 {
-    memset( _aucBuffer, 0, SERIAL_BUFFER_SIZE ) ;
+    memset( _aucBuffer, 0, UART_BUFFER_SIZE ) ;
     _iHead=0 ;
     _iTail=0 ;
 }
 
 void RingBuffer::store_char( uint8_t c )
 {
-  int i = (uint32_t)(_iHead + 1) % SERIAL_BUFFER_SIZE ;
+  int i = (uint32_t)(_iHead + 1) % UART_BUFFER_SIZE ;
 
   // if we should be storing the received character into the location
   // just before the tail (meaning that the head would advance to the

cores/arduino/RingBuffer.h

@@ -23,12 +23,12 @@
 // using a ring buffer (I think), in which head is the index of the location
 // to which to write the next incoming character and tail is the index of the
 // location from which to read.
-#define SERIAL_BUFFER_SIZE 256
+#define UART_BUFFER_SIZE 64
 
 class RingBuffer
 {
 public:
-	uint8_t _aucBuffer[SERIAL_BUFFER_SIZE] ;
+	uint8_t _aucBuffer[UART_BUFFER_SIZE] ;
 	int _iHead ;
 	int _iTail ;
 	bool _buffer_overflow ;

cores/arduino/UARTClass.cpp

@@ -134,7 +134,7 @@ uint32_t UARTClass::getInterruptPriority()
 
 int UARTClass::available( void )
 {
-  return (uint32_t)(SERIAL_BUFFER_SIZE + _rx_buffer->_iHead - _rx_buffer->_iTail) % SERIAL_BUFFER_SIZE;
+  return (uint32_t)(UART_BUFFER_SIZE + _rx_buffer->_iHead - _rx_buffer->_iTail) % UART_BUFFER_SIZE;
 }
 
 int UARTClass::availableForWrite(void)
@@ -143,7 +143,7 @@ int UARTClass::availableForWrite(void)
     return(0);
   int head = _tx_buffer->_iHead;
   int tail = _tx_buffer->_iTail;
-  if (head >= tail) return SERIAL_BUFFER_SIZE - 1 - head + tail;
+  if (head >= tail) return UART_BUFFER_SIZE - 1 - head + tail;
   return tail - head - 1;
 }
 
@@ -162,7 +162,7 @@ int UARTClass::read( void )
     return -1;
 
   uint8_t uc = _rx_buffer->_aucBuffer[_rx_buffer->_iTail];
-  _rx_buffer->_iTail = (unsigned int)(_rx_buffer->_iTail + 1) % SERIAL_BUFFER_SIZE;
+  _rx_buffer->_iTail = (unsigned int)(_rx_buffer->_iTail + 1) % UART_BUFFER_SIZE;
   return uc;
 }
 
@@ -182,7 +182,7 @@ size_t UARTClass::write( const uint8_t uc_data )
   if (_tx_buffer->_iTail != _tx_buffer->_iHead)
   {
     // If busy we buffer
-    int l = (_tx_buffer->_iHead + 1) % SERIAL_BUFFER_SIZE;
+    int l = (_tx_buffer->_iHead + 1) % UART_BUFFER_SIZE;
     while (_tx_buffer->_iTail == l)
       ; // Spin locks if we're about to overwrite the buffer. This continues once the data is sent
 
@@ -215,7 +215,7 @@ void UARTClass::IrqHandler( void )
   {
     if (_tx_buffer->_iTail != _tx_buffer->_iHead) {
       uart_poll_out(CONFIG_UART_CONSOLE_INDEX, _tx_buffer->_aucBuffer[_tx_buffer->_iTail]);
-      _tx_buffer->_iTail = (unsigned int)(_tx_buffer->_iTail + 1) % SERIAL_BUFFER_SIZE;
+      _tx_buffer->_iTail = (unsigned int)(_tx_buffer->_iTail + 1) % UART_BUFFER_SIZE;
     }
     else
     {

system/libarc32_arduino101/framework/include/infra/port.h

@@ -41,7 +41,7 @@
  * @{
  */
 
-#define MAX_PORTS       50
+#define MAX_PORTS       6
 
 
 #ifndef CONFIG_INFRA_IS_MASTER

system/libarc32_arduino101/framework/include/platform.h

@@ -39,12 +39,12 @@
 #define CPU_ID_HOST 3
 #define NUM_CPU     4
 
-#define SERIAL_BUFFER_SIZE 256
+#define CDCACM_BUFFER_SIZE 256
 
 struct cdc_ring_buffer
 {
     /** Ring buffer data */
-    uint8_t data[SERIAL_BUFFER_SIZE];
+    uint8_t data[CDCACM_BUFFER_SIZE];
     /** Ring buffer head pointer, modified by producer */
     int head;
     /** Ring buffer head pointer, modified by consumer */