HardwareSerial improvements

hardware/arduino/avr/cores/arduino/Arduino.h

@@ -87,6 +87,10 @@ void yield(void);
 #define bitClear(value, bit) ((value) &= ~(1UL << (bit)))
 #define bitWrite(value, bit, bitvalue) (bitvalue ? bitSet(value, bit) : bitClear(value, bit))
 
+// avr-libc defines _NOP() since 1.6.2
+#ifndef _NOP
+#define _NOP() do { __asm__ volatile ("nop"); } while (0)
+#endif
 
 typedef unsigned int word;
 
@@ -195,6 +199,10 @@ extern const uint8_t PROGMEM digital_pin_to_timer_PGM[];
 #include "WCharacter.h"
 #include "WString.h"
 #include "HardwareSerial.h"
+#include "USBAPI.h"
+#if defined(HAVE_HWSERIAL0) && defined(HAVE_CDCSERIAL)
+#error "Targets with both UART0 and CDC serial not supported"
+#endif
 
 uint16_t makeWord(uint16_t w);
 uint16_t makeWord(byte h, byte l);

hardware/arduino/avr/cores/arduino/HardwareSerial.h

@@ -46,14 +46,9 @@ class HardwareSerial : public Stream
     volatile uint8_t *_ucsrb;
     volatile uint8_t *_ucsrc;
     volatile uint8_t *_udr;
-    uint8_t _rxen;
-    uint8_t _txen;
-    uint8_t _rxcie;
-    uint8_t _udrie;
-    uint8_t _u2x;
-    bool transmitting;
+    // Has any byte been written to the UART since begin()
+    bool _written;
 
-  public:
     volatile uint8_t _rx_buffer_head;
     volatile uint8_t _rx_buffer_tail;
     volatile uint8_t _tx_buffer_head;
@@ -65,11 +60,11 @@ class HardwareSerial : public Stream
     unsigned char _rx_buffer[SERIAL_BUFFER_SIZE];
     unsigned char _tx_buffer[SERIAL_BUFFER_SIZE];
 
+  public:
     HardwareSerial(
       volatile uint8_t *ubrrh, volatile uint8_t *ubrrl,
       volatile uint8_t *ucsra, volatile uint8_t *ucsrb,
-      volatile uint8_t *ucsrc, volatile uint8_t *udr,
-      uint8_t rxen, uint8_t txen, uint8_t rxcie, uint8_t udrie, uint8_t u2x);
+      volatile uint8_t *ucsrc, volatile uint8_t *udr);
     void begin(unsigned long);
     void begin(unsigned long, uint8_t);
     void end();
@@ -84,6 +79,10 @@ class HardwareSerial : public Stream
     inline size_t write(int n) { return write((uint8_t)n); }
     using Print::write; // pull in write(str) and write(buf, size) from Print
     operator bool();
+
+    // Interrupt handlers - Not intended to be called externally
+    void _rx_complete_irq(void);
+    void _tx_udr_empty_irq(void);
 };
 
 // Define config for Serial.begin(baud, config);
@@ -114,18 +113,19 @@ class HardwareSerial : public Stream
 
 #if defined(UBRRH) || defined(UBRR0H)
   extern HardwareSerial Serial;
-#elif defined(USBCON)
-  #include "USBAPI.h"
-//  extern HardwareSerial Serial_;  
+  #define HAVE_HWSERIAL0
 #endif
 #if defined(UBRR1H)
   extern HardwareSerial Serial1;
+  #define HAVE_HWSERIAL1
 #endif
 #if defined(UBRR2H)
   extern HardwareSerial Serial2;
+  #define HAVE_HWSERIAL2
 #endif
 #if defined(UBRR3H)
   extern HardwareSerial Serial3;
+  #define HAVE_HWSERIAL3
 #endif
 
 extern void serialEventRun(void) __attribute__((weak));

hardware/arduino/avr/cores/arduino/HardwareSerial0.cpp

@@ -0,0 +1,54 @@
+#include "Arduino.h"
+#include "HardwareSerial.h"
+
+// Each HardwareSerial is defined in its own file, sine the linker pulls
+// in the entire file when any element inside is used. --gc-sections can
+// additionally cause unused symbols to be dropped, but ISRs have the
+// "used" attribute so are never dropped and they keep the
+// HardwareSerial instance in as well. Putting each instance in its own
+// file prevents the linker from pulling in any unused instances in the
+// first place.
+
+#if defined(HAVE_HWSERIAL0)
+
+#if defined(USART_RX_vect)
+  ISR(USART_RX_vect)
+#elif defined(USART0_RX_vect)
+  ISR(USART0_RX_vect)
+#elif defined(USART_RXC_vect)
+  ISR(USART_RXC_vect) // ATmega8
+#else
+  #error "Don't know what the Data Received vector is called for the first UART"
+#endif
+  {
+    Serial._rx_complete_irq();
+  }
+
+#if defined(UART0_UDRE_vect)
+ISR(UART0_UDRE_vect)
+#elif defined(UART_UDRE_vect)
+ISR(UART_UDRE_vect)
+#elif defined(USART0_UDRE_vect)
+ISR(USART0_UDRE_vect)
+#elif defined(USART_UDRE_vect)
+ISR(USART_UDRE_vect)
+#else
+  #error "Don't know what the Data Register Empty vector is called for the first UART"
+#endif
+{
+  Serial._tx_udr_empty_irq();
+}
+
+#if defined(UBRRH) && defined(UBRRL)
+  HardwareSerial Serial(&UBRRH, &UBRRL, &UCSRA, &UCSRB, &UCSRC, &UDR);
+#else
+  HardwareSerial Serial(&UBRR0H, &UBRR0L, &UCSR0A, &UCSR0B, &UCSR0C, &UDR0);
+#endif
+
+// Function that can be weakly referenced by serialEventRun to prevent
+// pulling in this file if it's not otherwise used.
+bool Serial0_available() {
+  return Serial.available();
+}
+
+#endif // HAVE_HWSERIAL0

hardware/arduino/avr/cores/arduino/HardwareSerial1.cpp

@@ -0,0 +1,54 @@
+#include "Arduino.h"
+#include "HardwareSerial.h"
+
+// Each HardwareSerial is defined in its own file, sine the linker pulls
+// in the entire file when any element inside is used. --gc-sections can
+// additionally cause unused symbols to be dropped, but ISRs have the
+// "used" attribute so are never dropped and they keep the
+// HardwareSerial instance in as well. Putting each instance in its own
+// file prevents the linker from pulling in any unused instances in the
+// first place.
+
+#if defined(HAVE_HWSERIAL1)
+
+#if defined(USART_RX_vect)
+  ISR(USART_RX_vect)
+#elif defined(USART1_RX_vect)
+  ISR(USART1_RX_vect)
+#elif defined(USART_RXC_vect)
+  ISR(USART_RXC_vect) // ATmega8
+#else
+  #error "Don't know what the Data Received vector is called for the first UART"
+#endif
+  {
+    Serial1._rx_complete_irq();
+  }
+
+#if defined(UART1_UDRE_vect)
+ISR(UART1_UDRE_vect)
+#elif defined(UART_UDRE_vect)
+ISR(UART_UDRE_vect)
+#elif defined(USART1_UDRE_vect)
+ISR(USART1_UDRE_vect)
+#elif defined(USART_UDRE_vect)
+ISR(USART_UDRE_vect)
+#else
+  #error "Don't know what the Data Register Empty vector is called for the first UART"
+#endif
+{
+  Serial1._tx_udr_empty_irq();
+}
+
+#if defined(UBRRH) && defined(UBRRL)
+  HardwareSerial Serial1(&UBRRH, &UBRRL, &UCSRA, &UCSRB, &UCSRC, &UDR);
+#else
+  HardwareSerial Serial1(&UBRR1H, &UBRR1L, &UCSR1A, &UCSR1B, &UCSR1C, &UDR1);
+#endif
+
+// Function that can be weakly referenced by serialEventRun to prevent
+// pulling in this file if it's not otherwise used.
+bool Serial1_available() {
+  return Serial1.available();
+}
+
+#endif // HAVE_HWSERIAL1

hardware/arduino/avr/cores/arduino/HardwareSerial2.cpp

@@ -0,0 +1,54 @@
+#include "Arduino.h"
+#include "HardwareSerial.h"
+
+// Each HardwareSerial is defined in its own file, sine the linker pulls
+// in the entire file when any element inside is used. --gc-sections can
+// additionally cause unused symbols to be dropped, but ISRs have the
+// "used" attribute so are never dropped and they keep the
+// HardwareSerial instance in as well. Putting each instance in its own
+// file prevents the linker from pulling in any unused instances in the
+// first place.
+
+#if defined(HAVE_HWSERIAL2)
+
+#if defined(USART_RX_vect)
+  ISR(USART_RX_vect)
+#elif defined(USART2_RX_vect)
+  ISR(USART2_RX_vect)
+#elif defined(USART_RXC_vect)
+  ISR(USART_RXC_vect) // ATmega8
+#else
+  #error "Don't know what the Data Received vector is called for the first UART"
+#endif
+  {
+    Serial2._rx_complete_irq();
+  }
+
+#if defined(UART2_UDRE_vect)
+ISR(UART2_UDRE_vect)
+#elif defined(UART_UDRE_vect)
+ISR(UART_UDRE_vect)
+#elif defined(USART2_UDRE_vect)
+ISR(USART2_UDRE_vect)
+#elif defined(USART_UDRE_vect)
+ISR(USART_UDRE_vect)
+#else
+  #error "Don't know what the Data Register Empty vector is called for the first UART"
+#endif
+{
+  Serial2._tx_udr_empty_irq();
+}
+
+#if defined(UBRRH) && defined(UBRRL)
+  HardwareSerial Serial2(&UBRRH, &UBRRL, &UCSRA, &UCSRB, &UCSRC, &UDR);
+#else
+  HardwareSerial Serial2(&UBRR2H, &UBRR2L, &UCSR2A, &UCSR2B, &UCSR2C, &UDR2);
+#endif
+
+// Function that can be weakly referenced by serialEventRun to prevent
+// pulling in this file if it's not otherwise used.
+bool Serial2_available() {
+  return Serial2.available();
+}
+
+#endif // HAVE_HWSERIAL2

hardware/arduino/avr/cores/arduino/HardwareSerial3.cpp

@@ -0,0 +1,54 @@
+#include "Arduino.h"
+#include "HardwareSerial.h"
+
+// Each HardwareSerial is defined in its own file, sine the linker pulls
+// in the entire file when any element inside is used. --gc-sections can
+// additionally cause unused symbols to be dropped, but ISRs have the
+// "used" attribute so are never dropped and they keep the
+// HardwareSerial instance in as well. Putting each instance in its own
+// file prevents the linker from pulling in any unused instances in the
+// first place.
+
+#if defined(HAVE_HWSERIAL3)
+
+#if defined(USART_RX_vect)
+  ISR(USART_RX_vect)
+#elif defined(USART3_RX_vect)
+  ISR(USART3_RX_vect)
+#elif defined(USART_RXC_vect)
+  ISR(USART_RXC_vect) // ATmega8
+#else
+  #error "Don't know what the Data Received vector is called for the first UART"
+#endif
+  {
+    Serial3._rx_complete_irq();
+  }
+
+#if defined(UART3_UDRE_vect)
+ISR(UART3_UDRE_vect)
+#elif defined(UART_UDRE_vect)
+ISR(UART_UDRE_vect)
+#elif defined(USART3_UDRE_vect)
+ISR(USART3_UDRE_vect)
+#elif defined(USART_UDRE_vect)
+ISR(USART_UDRE_vect)
+#else
+  #error "Don't know what the Data Register Empty vector is called for the first UART"
+#endif
+{
+  Serial3._tx_udr_empty_irq();
+}
+
+#if defined(UBRRH) && defined(UBRRL)
+  HardwareSerial Serial3(&UBRRH, &UBRRL, &UCSRA, &UCSRB, &UCSRC, &UDR);
+#else
+  HardwareSerial Serial3(&UBRR3H, &UBRR3L, &UCSR3A, &UCSR3B, &UCSR3C, &UDR3);
+#endif
+
+// Function that can be weakly referenced by serialEventRun to prevent
+// pulling in this file if it's not otherwise used.
+bool Serial3_available() {
+  return Serial3.available();
+}
+
+#endif // HAVE_HWSERIAL3

hardware/arduino/avr/cores/arduino/USBAPI.h

@@ -55,6 +55,8 @@ class Serial_ : public Stream
 };
 extern Serial_ Serial;
 
+#define HAVE_CDCSERIAL
+
 //================================================================================
 //================================================================================
 //	Mouse