diff options
Diffstat (limited to 'LUFA/Drivers/Peripheral/AVRU4U6U7')
| -rw-r--r-- | LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.c | 54 | ||||
| -rw-r--r-- | LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h | 141 |
2 files changed, 195 insertions, 0 deletions
diff --git a/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.c b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.c new file mode 100644 index 000000000..6028bbae9 --- /dev/null +++ b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.c @@ -0,0 +1,54 @@ +/*
+ Copyright (C) Dean Camera, 2010.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.fourwalledcubicle.com
+*/
+
+#include "TWI.h"
+
+bool TWI_StartTransmission(uint8_t SlaveAddress)
+{
+ for (;;)
+ {
+ uint8_t IterationsRemaining = 50;
+ bool BusCaptured = false;
+
+ while (IterationsRemaining-- && !BusCaptured)
+ {
+ TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));
+ while (!(TWCR & (1 << TWINT)));
+
+ switch (TWSR & TW_STATUS_MASK)
+ {
+ case TW_START:
+ case TW_REP_START:
+ BusCaptured = true;
+ break;
+ case TW_MT_ARB_LOST:
+ continue;
+ default:
+ return false;
+ }
+ }
+
+ if (!(BusCaptured))
+ return false;
+
+ TWDR = SlaveAddress;
+ TWCR = ((1 << TWINT) | (1 << TWEN));
+ while (!(TWCR & (1 << TWINT)));
+
+ GPIOR0 = (TWSR & TW_STATUS_MASK);
+
+ switch (TWSR & TW_STATUS_MASK)
+ {
+ case TW_MT_SLA_ACK:
+ case TW_MR_SLA_ACK:
+ return true;
+ default:
+ TWI_StopTransmission();
+ break;
+ }
+ }
+}
diff --git a/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h new file mode 100644 index 000000000..0247668dc --- /dev/null +++ b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h @@ -0,0 +1,141 @@ +/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2010.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.fourwalledcubicle.com
+*/
+
+/*
+ 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
+ *
+ * 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
+ *
+ * @{
+ */
+
+#ifndef __TWI_AVRU4U6U7_H__
+#define __TWI_AVRU4U6U7_H__
+
+ /* Includes: */
+ #include "../../../Common/Common.h"
+
+ #include <avr/io.h>
+ #include <stdbool.h>
+ #include <util/twi.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: */
+ /* Pseudo-Function Macros: */
+ #if defined(__DOXYGEN__)
+ /** Initializes 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);
+
+ /** 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);
+ #else
+ #define TWI_Init() MACROS{ TWCR |= (1 << TWEN); }MACROE
+ #define TWI_ShutDown() MACROS{ TWCR &= ~(1 << TWEN); }MACROE
+ #endif
+
+ /* Inline Functions: */
+ /** Sends a TWI STOP onto the TWI bus, terminating communication with the currently addressed device. */
+ 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 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(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 Byte Location where the read byte is to be stored
+ * \param LastByte Indicates if the byte should be ACKed if false, NAKed if true
+ *
+ * \return Boolean true if the byte reception sucessfully completed, false otherwise
+ */
+ static inline bool TWI_ReceiveByte(uint8_t* Byte, 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 SlaveAddress Address of the slave TWI device to communicate with
+ *
+ * \return Boolean true if the device is ready for data, false otherwise
+ */
+ bool TWI_StartTransmission(uint8_t SlaveAddress);
+
+ /* Disable C linkage for C++ Compilers: */
+ #if defined(__cplusplus)
+ }
+ #endif
+
+#endif
+
+/** @} */
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