/*
LUFA Library
- Copyright (C) Dean Camera, 2011.
+ Copyright (C) Dean Camera, 2013.
dean [at] fourwalledcubicle [dot] com
www.lufa-lib.org
*/
/*
- Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+ Copyright 2013 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
advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
- The author disclaim all warranties with regard to this
+ The author disclaims 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
this software.
*/
+#include "../../../Common/Common.h"
+#if (ARCH == ARCH_AVR8) && defined(TWCR)
+
#define __INCLUDE_FROM_TWI_C
#include "../TWI.h"
TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));
TimeoutRemaining = (TimeoutMS * 100);
- while (TimeoutRemaining-- && !(BusCaptured))
+ while (TimeoutRemaining && !(BusCaptured))
{
if (TWCR & (1 << TWINT))
{
}
_delay_us(10);
+ TimeoutRemaining--;
}
if (!(TimeoutRemaining))
TWCR = ((1 << TWINT) | (1 << TWEN));
TimeoutRemaining = (TimeoutMS * 100);
- while (TimeoutRemaining--)
+ while (TimeoutRemaining)
{
if (TWCR & (1 << TWINT))
break;
_delay_us(10);
+ TimeoutRemaining--;
}
if (!(TimeoutRemaining))
}
}
+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);
+}
+
+bool TWI_ReceiveByte(uint8_t* const Byte,
+ const bool LastByte)
+{
+ uint8_t TWCRMask;
+
+ if (LastByte)
+ TWCRMask = ((1 << TWINT) | (1 << TWEN));
+ else
+ TWCRMask = ((1 << TWINT) | (1 << TWEN) | (1 << TWEA));
+
+ TWCR = TWCRMask;
+ while (!(TWCR & (1 << TWINT)));
+ *Byte = TWDR;
+
+ uint8_t Status = (TWSR & TW_STATUS_MASK);
+
+ return ((LastByte) ? (Status == TW_MR_DATA_NACK) : (Status == TW_MR_DATA_ACK));
+}
+
uint8_t TWI_ReadPacket(const uint8_t SlaveAddress,
const uint8_t TimeoutMS,
const uint8_t* InternalAddress,
- const uint8_t InternalAddressLen,
+ uint8_t InternalAddressLen,
uint8_t* Buffer,
uint8_t Length)
{
uint8_t ErrorCode;
-
- if ((ErrorCode = TWI_WritePacket(SlaveAddress, TimeoutMS, InternalAddress, InternalAddressLen,
- NULL, 0)) != TWI_ERROR_NoError)
- {
- return ErrorCode;
- }
- if ((ErrorCode = TWI_StartTransmission((SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_READ,
- TimeoutMS)) == TWI_ERROR_NoError)
+ if ((ErrorCode = TWI_StartTransmission((SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_WRITE,
+ TimeoutMS)) == TWI_ERROR_NoError)
{
- while (Length--)
+ while (InternalAddressLen--)
{
- if (!(TWI_ReceiveByte(Buffer++, (Length == 0))))
+ if (!(TWI_SendByte(*(InternalAddress++))))
{
ErrorCode = TWI_ERROR_SlaveNAK;
break;
}
}
-
- TWI_StopTransmission();
+
+ if ((ErrorCode = TWI_StartTransmission((SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_READ,
+ TimeoutMS)) == TWI_ERROR_NoError)
+ {
+ while (Length--)
+ {
+ if (!(TWI_ReceiveByte(Buffer++, (Length == 0))))
+ {
+ ErrorCode = TWI_ERROR_SlaveNAK;
+ break;
+ }
+ }
+
+ TWI_StopTransmission();
+ }
}
-
+
return ErrorCode;
}
break;
}
}
-
+
TWI_StopTransmission();
}
-
+
return ErrorCode;
}
+
+#endif