diff options
Diffstat (limited to 'LUFA/Drivers/Peripheral/AVR8')
-rw-r--r-- | LUFA/Drivers/Peripheral/AVR8/Serial_AVR8.h | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/LUFA/Drivers/Peripheral/AVR8/Serial_AVR8.h b/LUFA/Drivers/Peripheral/AVR8/Serial_AVR8.h index f951f6b74..e8860a511 100644 --- a/LUFA/Drivers/Peripheral/AVR8/Serial_AVR8.h +++ b/LUFA/Drivers/Peripheral/AVR8/Serial_AVR8.h @@ -210,14 +210,39 @@ 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; } |