diff options
Diffstat (limited to 'LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h')
| -rw-r--r-- | LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h new file mode 100644 index 0000000..a797990 --- /dev/null +++ b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h @@ -0,0 +1,155 @@ +/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2010.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.lufa-lib.org
+*/
+
+/*
+ Copyright 2010 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
+ without fee, provided that the above copyright notice appear in
+ all copies and that both that the copyright notice and this
+ permission notice and warranty disclaimer appear in supporting
+ documentation, and that the name of the author not be used in
+ advertising or publicity pertaining to distribution of the
+ software without specific, written prior permission.
+
+ The author disclaim all warranties with regard to this
+ software, including all implied warranties of merchantability
+ and fitness. In no event shall the author be liable for any
+ special, indirect or consequential damages or any damages
+ whatsoever resulting from loss of use, data or profits, whether
+ in an action of contract, negligence or other tortious action,
+ arising out of or in connection with the use or performance of
+ this software.
+*/
+
+/** \file
+ * \brief TWI peripheral driver for the U7, U6 and U4 USB AVRs.
+ *
+ * Master mode TWI driver for the AT90USB1287, AT90USB1286, AT90USB647, AT90USB646, ATMEGA16U4 and ATMEGA32U4 AVRs.
+ *
+ * \note This file should not be included directly. It is automatically included as needed by the TWI driver
+ * dispatch header located in LUFA/Drivers/Peripheral/TWI.h.
+ */
+
+/** \ingroup Group_TWI
+ * @defgroup Group_TWI_AVRU4U6U7 Series U4, U6 and U7 Model TWI Driver
+ *
+ * Master mode TWI driver for the AT90USB1287, AT90USB1286, AT90USB647, AT90USB646, ATMEGA16U4 and ATMEGA32U4 AVRs.
+ *
+ * \note This file should not be included directly. It is automatically included as needed by the TWI driver
+ * dispatch header located in LUFA/Drivers/Peripheral/TWI.h.
+ *
+ * @{
+ */
+
+#ifndef __TWI_AVRU4U6U7_H__
+#define __TWI_AVRU4U6U7_H__
+
+ /* Includes: */
+ #include "../../../Common/Common.h"
+
+ #include <avr/io.h>
+ #include <stdbool.h>
+ #include <util/twi.h>
+ #include <util/delay.h>
+
+ /* Enable C linkage for C++ Compilers: */
+ #if defined(__cplusplus)
+ extern "C" {
+ #endif
+
+ /* Preprocessor Checks: */
+ #if !defined(__INCLUDE_FROM_TWI_H)
+ #error Do not include this file directly. Include LUFA/Drivers/Peripheral/TWI.h instead.
+ #endif
+
+ /* Public Interface - May be used in end-application: */
+ /* Inline Functions: */
+ /** Initialises the TWI hardware into master mode, ready for data transmission and reception. This must be
+ * before any other TWI operations.
+ */
+ static inline void TWI_Init(void) ATTR_ALWAYS_INLINE;
+ static inline void TWI_Init(void)
+ {
+ TWCR |= (1 << TWEN);
+ }
+
+ /** Turns off the TWI driver hardware. If this is called, any further TWI operations will require a call to
+ * \ref TWI_Init() before the TWI can be used again.
+ */
+ static inline void TWI_ShutDown(void) ATTR_ALWAYS_INLINE;
+ static inline void TWI_ShutDown(void)
+ {
+ TWCR &= ~(1 << TWEN);
+ }
+
+ /** Sends a TWI STOP onto the TWI bus, terminating communication with the currently addressed device. */
+ static inline void TWI_StopTransmission(void) ATTR_ALWAYS_INLINE;
+ static inline void TWI_StopTransmission(void)
+ {
+ TWCR = ((1 << TWINT) | (1 << TWSTO) | (1 << TWEN));
+ }
+
+ /** Sends a byte to the currently addressed device on the TWI bus.
+ *
+ * \param[in] Byte Byte to send to the currently addressed device
+ *
+ * \return Boolean true if the recipient ACKed the byte, false otherwise
+ */
+ static inline bool TWI_SendByte(const uint8_t Byte)
+ {
+ TWDR = Byte;
+ TWCR = ((1 << TWINT) | (1 << TWEN));
+ while (!(TWCR & (1 << TWINT)));
+
+ return ((TWSR & TW_STATUS_MASK) == TW_MT_DATA_ACK);
+ }
+
+ /** Receives a byte from the currently addressed device on the TWI bus.
+ *
+ * \param[in] Byte Location where the read byte is to be stored
+ * \param[in] LastByte Indicates if the byte should be ACKed if false, NAKed if true
+ *
+ * \return Boolean true if the byte reception successfully completed, false otherwise
+ */
+ static inline bool TWI_ReceiveByte(uint8_t* const Byte,
+ const bool LastByte)
+ {
+ uint8_t TWCRMask = ((1 << TWINT) | (1 << TWEN));
+
+ if (!(LastByte))
+ TWCRMask |= (1 << TWEA);
+
+ TWCR = TWCRMask;
+ while (!(TWCR & (1 << TWINT)));
+ *Byte = TWDR;
+
+ return ((TWSR & TW_STATUS_MASK) == TW_MR_DATA_ACK);
+ }
+
+ /* Function Prototypes: */
+ /** Begins a master mode TWI bus communication with the given slave device address.
+ *
+ * \param[in] SlaveAddress Address of the slave TWI device to communicate with
+ * \param[in] TimeoutMS Timeout period within which the slave must respond, in milliseconds
+ *
+ * \return Boolean true if the device is ready for data, false otherwise
+ */
+ bool TWI_StartTransmission(const uint8_t SlaveAddress,
+ const uint8_t TimeoutMS);
+
+ /* Disable C linkage for C++ Compilers: */
+ #if defined(__cplusplus)
+ }
+ #endif
+
+#endif
+
+/** @} */
+
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