/*
LUFA Library
- Copyright (C) Dean Camera, 2014.
+ Copyright (C) Dean Camera, 2015.
dean [at] fourwalledcubicle [dot] com
www.lufa-lib.org
*/
/*
- Copyright 2014 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+ Copyright 2015 Dean Camera (dean [at] fourwalledcubicle [dot] com)
Permission to use, copy, modify, distribute, and sell this
software and its documentation for any purpose is hereby granted
/** Initializes the USART, ready for serial data transmission and reception. This initializes the interface to
* standard 8-bit, no parity, 1 stop bit settings suitable for most applications.
*
- * \param[in] BaudRate Serial baud rate, in bits per second.
+ * \param[in] BaudRate Serial baud rate, in bits per second. This should be the target baud rate regardless of the
+ * \c DoubleSpeed parameter's value.
* \param[in] DoubleSpeed Enables double speed mode when set, halving the sample time to double the baud rate.
*/
static inline void Serial_Init(const uint32_t BaudRate,
return ((UCSR1A & (1 << RXC1)) ? true : false);
}
+ /** Indicates whether there is hardware buffer space for a new transmit on the USART. This
+ * function can be used to determine if a call to \ref Serial_SendByte() will block in advance.
+ *
+ * \return Boolean \c true if a character can be queued for transmission immediately, \c false otherwise.
+ */
+ static inline bool Serial_IsSendReady(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
+ static inline bool Serial_IsSendReady(void)
+ {
+ return ((UCSR1A & (1 << UDRE1)) ? true : false);
+ }
+
+ /** Indicates whether the hardware USART transmit buffer is completely empty, indicating all
+ * pending transmissions have completed.
+ *
+ * \return Boolean \c true if no characters are buffered for transmission, \c false otherwise.
+ */
+ static inline bool Serial_IsSendComplete(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
+ static inline bool Serial_IsSendComplete(void)
+ {
+ return ((UCSR1A & (1 << TXC1)) ? true : false);
+ }
+
/** Transmits a given byte through the USART.
*
+ * \note If no buffer space is available in the hardware USART, this function will block. To check if
+ * space is available before calling this function, see \ref Serial_IsSendReady().
+ *
* \param[in] DataByte Byte to transmit through the USART.
*/
static inline void Serial_SendByte(const char DataByte) ATTR_ALWAYS_INLINE;
static inline void Serial_SendByte(const char DataByte)
{
- while (!(UCSR1A & (1 << UDRE1)));
+ while (!(Serial_IsSendReady()));
UDR1 = DataByte;
}