diff options
Diffstat (limited to 'LUFA/Drivers/Peripheral/XMEGA/Serial_XMEGA.h')
| -rw-r--r-- | LUFA/Drivers/Peripheral/XMEGA/Serial_XMEGA.h | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/LUFA/Drivers/Peripheral/XMEGA/Serial_XMEGA.h b/LUFA/Drivers/Peripheral/XMEGA/Serial_XMEGA.h index 1161ef674..e7f9fee24 100644 --- a/LUFA/Drivers/Peripheral/XMEGA/Serial_XMEGA.h +++ b/LUFA/Drivers/Peripheral/XMEGA/Serial_XMEGA.h @@ -216,8 +216,37 @@ return ((USART->STATUS & USART_RXCIF_bm) ? 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. + * + * \param[in,out] USART Pointer to the base of the USART peripheral within the device. + * + * \return Boolean \c true if a character can be queued for transmission immediately, \c false otherwise. + */ + static inline bool Serial_IsSendReady(USART_t* const USART) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); + static inline bool Serial_IsSendReady(USART_t* const USART) + { + return (USART->STATUS & USART_DREIF_bm) ? true : false); + } + + /** Indicates whether the hardware USART transmit buffer is completely empty, indicating all + * pending transmissions have completed. + * + * \param[in,out] USART Pointer to the base of the USART peripheral within the device. + * + * \return Boolean \c true if no characters are buffered for transmission, \c false otherwise. + */ + static inline bool Serial_IsSendComplete(USART_t* const USART) ATTR_ALWAYS_INLINE ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); + static inline bool Serial_IsSendComplete(USART_t* const USART) + { + return (USART->STATUS & USART_TCXIF_bm) ? 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,out] USART Pointer to the base of the USART peripheral within the device. * \param[in] DataByte Byte to transmit through the USART. */ @@ -226,7 +255,7 @@ static inline void Serial_SendByte(USART_t* const USART, const char DataByte) { - while (!(USART->STATUS & USART_DREIF_bm)); + while (!(Serial_IsSendReady(USART)); USART->DATA = DataByte; } |