AVRTools
A Library for the AVR ATmega328 and ATmega2560 Microcontrollers
Classes | Namespaces | Enumerations | Functions
USART1.h File Reference

This file provides functions that offer high-level interfaces to USART1 hardware, which is available on Arduino Mega (ATMega2560). More...

#include "Writer.h"
#include "Reader.h"
#include <stdint.h>
#include <stddef.h>
Include dependency graph for USART1.h:

Go to the source code of this file.

Classes

class  Serial1
 Provides a high-end interface to serial communications using USART1. More...
 

Namespaces

 USART1
 This namespace bundles a high-level buffered interface to the USART1 hardware. It provides logical cohesion and prevents namespace collisions.
 

Enumerations

enum  UsartSerialConfiguration {
  kSerial_5N1, kSerial_6N1, kSerial_7N1, kSerial_8N1,
  kSerial_5N2, kSerial_6N2, kSerial_7N2, kSerial_8N2,
  kSerial_5E1, kSerial_6E1, kSerial_7E1, kSerial_8E1,
  kSerial_5E2, kSerial_6E2, kSerial_7E2, kSerial_8E2,
  kSerial_5O1, kSerial_6O1, kSerial_7O1, kSerial_8O1,
  kSerial_5O2, kSerial_6O2, kSerial_7O2, kSerial_8O2,
  kSerial_5N1, kSerial_6N1, kSerial_7N1, kSerial_8N1,
  kSerial_5N2, kSerial_6N2, kSerial_7N2, kSerial_8N2,
  kSerial_5E1, kSerial_6E1, kSerial_7E1, kSerial_8E1,
  kSerial_5E2, kSerial_6E2, kSerial_7E2, kSerial_8E2,
  kSerial_5O1, kSerial_6O1, kSerial_7O1, kSerial_8O1,
  kSerial_5O2, kSerial_6O2, kSerial_7O2, kSerial_8O2,
  kSerial_5N1, kSerial_6N1, kSerial_7N1, kSerial_8N1,
  kSerial_5N2, kSerial_6N2, kSerial_7N2, kSerial_8N2,
  kSerial_5E1, kSerial_6E1, kSerial_7E1, kSerial_8E1,
  kSerial_5E2, kSerial_6E2, kSerial_7E2, kSerial_8E2,
  kSerial_5O1, kSerial_6O1, kSerial_7O1, kSerial_8O1,
  kSerial_5O2, kSerial_6O2, kSerial_7O2, kSerial_8O2,
  kSerial_5N1, kSerial_6N1, kSerial_7N1, kSerial_8N1,
  kSerial_5N2, kSerial_6N2, kSerial_7N2, kSerial_8N2,
  kSerial_5E1, kSerial_6E1, kSerial_7E1, kSerial_8E1,
  kSerial_5E2, kSerial_6E2, kSerial_7E2, kSerial_8E2,
  kSerial_5O1, kSerial_6O1, kSerial_7O1, kSerial_8O1,
  kSerial_5O2, kSerial_6O2, kSerial_7O2, kSerial_8O2
}
 This enum lists serial configuration in terms of data bits, parity, and stop bits. More...
 

Functions

void USART1::start (unsigned long baudRate, UsartSerialConfiguration config=kSerial_8N1)
 Initialize USART1 for buffered, asynchronous serial communications using interrupts. More...
 
void USART1::stop ()
 Stops buffered serial communications using interrupts on USART1. More...
 
size_t USART1::write (char c)
 Write a single byte to the transmit buffer. More...
 
size_t USART1::write (const char *c)
 Write a null-terminated string to the transmit buffer. More...
 
size_t USART1::write (const char *c, size_t n)
 Write a character array of given size to the transmit buffer. More...
 
size_t USART1::write (const uint8_t *c, size_t n)
 Write a byte array of given size to the transmit buffer. More...
 
void USART1::flush ()
 Flush transmit buffer. More...
 
int USART1::peek ()
 Examine the next character in the receive buffer without removing it from the buffer. More...
 
int USART1::read ()
 Return the next character in the receive buffer, removing it from the buffer. More...
 
bool USART1::available ()
 Determine if there is data in the receive buffer.. More...
 

Detailed Description

This file provides functions that offer high-level interfaces to USART1 hardware, which is available on Arduino Mega (ATMega2560).

These interfaces are buffered for both input and output and operate using interrupts associated with USART1. This means the transmit functions return immediately after queuing data in the output buffer for transmission and the transmission happens asynchronously, using dedicated USART1 hardware. Similarly, data is received asynchronously and placed into the input buffer.

The transmit and receive buffers are both ring buffers. If you try to queue more data than the transmit buffer can hold, the write functions will block until there is room in the buffer (as a result of data being transmitted). The receive buffer, however, will overwrite if it gets full. You must clear the receive buffer by reading it regularly when receiving significant amounts of data.

The sizes of the transmit and receive buffers can be set at compile time via macro constants. The default sizes are 32 bytes for the receive buffer and 64 bytes for the transmit buffer. To change these, define the macros USART1_RX_BUFFER_SIZE (for the receive buffer) and USART1_TX_BUFFER_SIZE (for the transmit buffer) to whatever sizes you need. You need to make these define these macros prior to compiling the file USART1.cpp.

Two interfaces are provided. USART1 is a functional interface that makes use of the buffering and asynchronous transmit and receive capabilities of the microcontrollers. However, USART1 is limited to transmitting and receiving byte and character streams.

Serial1 is the most advanced and capable interface to the USART1 hardware. Serial1 provides a object-oriented interface that includes the ability to read and write numbers of various types and in various formats, all asynchronously.

To use these functions, include USART1.h in your source code and link against USART1.cpp.

Note
Linking against USART1.cpp installs interrupt functions for transmit and receive on USART1 (interrupts USART1_UDRE and USART1_RX on Arduino Mega/ATmega2560). You cannot use the minimal interface to USART1 (from USARTMinimal.h) if you link against USART1.cpp. In particular, do not call initUSART1() or clearUSART1() if you link against USART1.cpp.

Enumeration Type Documentation

§ UsartSerialConfiguration

This enum lists serial configuration in terms of data bits, parity, and stop bits.

The format is kSerial_XYZ where

  • X = the number of data bits
  • Y = N, E, or O; where N = none, E = even, and O = odd
  • Z = the number of stop bits
Enumerator
kSerial_5N1 

5 data bits, no parity, 1 stop bit

kSerial_6N1 

6 data bits, no parity, 1 stop bit

kSerial_7N1 

7 data bits, no parity, 1 stop bit

kSerial_8N1 

8 data bits, no parity, 1 stop bit

kSerial_5N2 

5 data bits, no parity, 2 stop bits

kSerial_6N2 

6 data bits, no parity, 2 stop bits

kSerial_7N2 

7 data bits, no parity, 2 stop bits

kSerial_8N2 

8 data bits, no parity, 2 stop bits

kSerial_5E1 

5 data bits, even parity, 1 stop bit

kSerial_6E1 

6 data bits, even parity, 1 stop bit

kSerial_7E1 

7 data bits, even parity, 1 stop bit

kSerial_8E1 

8 data bits, even parity, 1 stop bit

kSerial_5E2 

5 data bits, even parity, 2 stop bits

kSerial_6E2 

6 data bits, even parity, 2 stop bits

kSerial_7E2 

7 data bits, even parity, 2 stop bits

kSerial_8E2 

8 data bits, even parity, 2 stop bits

kSerial_5O1 

5 data bits, odd parity, 1 stop bit

kSerial_6O1 

6 data bits, odd parity, 1 stop bit

kSerial_7O1 

7 data bits, odd parity, 1 stop bit

kSerial_8O1 

8 data bits, odd parity, 1 stop bit

kSerial_5O2 

5 data bits, odd parity, 2 stop bits

kSerial_6O2 

6 data bits, odd parity, 2 stop bits

kSerial_7O2 

7 data bits, odd parity, 2 stop bits

kSerial_8O2 

8 data bits, odd parity, 2 stop bits

kSerial_5N1 

5 data bits, no parity, 1 stop bit

kSerial_6N1 

6 data bits, no parity, 1 stop bit

kSerial_7N1 

7 data bits, no parity, 1 stop bit

kSerial_8N1 

8 data bits, no parity, 1 stop bit

kSerial_5N2 

5 data bits, no parity, 2 stop bits

kSerial_6N2 

6 data bits, no parity, 2 stop bits

kSerial_7N2 

7 data bits, no parity, 2 stop bits

kSerial_8N2 

8 data bits, no parity, 2 stop bits

kSerial_5E1 

5 data bits, even parity, 1 stop bit

kSerial_6E1 

6 data bits, even parity, 1 stop bit

kSerial_7E1 

7 data bits, even parity, 1 stop bit

kSerial_8E1 

8 data bits, even parity, 1 stop bit

kSerial_5E2 

5 data bits, even parity, 2 stop bits

kSerial_6E2 

6 data bits, even parity, 2 stop bits

kSerial_7E2 

7 data bits, even parity, 2 stop bits

kSerial_8E2 

8 data bits, even parity, 2 stop bits

kSerial_5O1 

5 data bits, odd parity, 1 stop bit

kSerial_6O1 

6 data bits, odd parity, 1 stop bit

kSerial_7O1 

7 data bits, odd parity, 1 stop bit

kSerial_8O1 

8 data bits, odd parity, 1 stop bit

kSerial_5O2 

5 data bits, odd parity, 2 stop bits

kSerial_6O2 

6 data bits, odd parity, 2 stop bits

kSerial_7O2 

7 data bits, odd parity, 2 stop bits

kSerial_8O2 

8 data bits, odd parity, 2 stop bits

kSerial_5N1 

5 data bits, no parity, 1 stop bit

kSerial_6N1 

6 data bits, no parity, 1 stop bit

kSerial_7N1 

7 data bits, no parity, 1 stop bit

kSerial_8N1 

8 data bits, no parity, 1 stop bit

kSerial_5N2 

5 data bits, no parity, 2 stop bits

kSerial_6N2 

6 data bits, no parity, 2 stop bits

kSerial_7N2 

7 data bits, no parity, 2 stop bits

kSerial_8N2 

8 data bits, no parity, 2 stop bits

kSerial_5E1 

5 data bits, even parity, 1 stop bit

kSerial_6E1 

6 data bits, even parity, 1 stop bit

kSerial_7E1 

7 data bits, even parity, 1 stop bit

kSerial_8E1 

8 data bits, even parity, 1 stop bit

kSerial_5E2 

5 data bits, even parity, 2 stop bits

kSerial_6E2 

6 data bits, even parity, 2 stop bits

kSerial_7E2 

7 data bits, even parity, 2 stop bits

kSerial_8E2 

8 data bits, even parity, 2 stop bits

kSerial_5O1 

5 data bits, odd parity, 1 stop bit

kSerial_6O1 

6 data bits, odd parity, 1 stop bit

kSerial_7O1 

7 data bits, odd parity, 1 stop bit

kSerial_8O1 

8 data bits, odd parity, 1 stop bit

kSerial_5O2 

5 data bits, odd parity, 2 stop bits

kSerial_6O2 

6 data bits, odd parity, 2 stop bits

kSerial_7O2 

7 data bits, odd parity, 2 stop bits

kSerial_8O2 

8 data bits, odd parity, 2 stop bits

kSerial_5N1 

5 data bits, no parity, 1 stop bit

kSerial_6N1 

6 data bits, no parity, 1 stop bit

kSerial_7N1 

7 data bits, no parity, 1 stop bit

kSerial_8N1 

8 data bits, no parity, 1 stop bit

kSerial_5N2 

5 data bits, no parity, 2 stop bits

kSerial_6N2 

6 data bits, no parity, 2 stop bits

kSerial_7N2 

7 data bits, no parity, 2 stop bits

kSerial_8N2 

8 data bits, no parity, 2 stop bits

kSerial_5E1 

5 data bits, even parity, 1 stop bit

kSerial_6E1 

6 data bits, even parity, 1 stop bit

kSerial_7E1 

7 data bits, even parity, 1 stop bit

kSerial_8E1 

8 data bits, even parity, 1 stop bit

kSerial_5E2 

5 data bits, even parity, 2 stop bits

kSerial_6E2 

6 data bits, even parity, 2 stop bits

kSerial_7E2 

7 data bits, even parity, 2 stop bits

kSerial_8E2 

8 data bits, even parity, 2 stop bits

kSerial_5O1 

5 data bits, odd parity, 1 stop bit

kSerial_6O1 

6 data bits, odd parity, 1 stop bit

kSerial_7O1 

7 data bits, odd parity, 1 stop bit

kSerial_8O1 

8 data bits, odd parity, 1 stop bit

kSerial_5O2 

5 data bits, odd parity, 2 stop bits

kSerial_6O2 

6 data bits, odd parity, 2 stop bits

kSerial_7O2 

7 data bits, odd parity, 2 stop bits

kSerial_8O2 

8 data bits, odd parity, 2 stop bits