X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/5a4def747897c1c6ffbe465506d846c7c686d3e9..0019fbd1294ccc9ecb0ac4ddb5d8c71efcf9597f:/LUFA/Drivers/Peripheral/TWI.c diff --git a/LUFA/Drivers/Peripheral/TWI.c b/LUFA/Drivers/Peripheral/TWI.c index 64f847544..2f4e4ed42 100644 --- a/LUFA/Drivers/Peripheral/TWI.c +++ b/LUFA/Drivers/Peripheral/TWI.c @@ -1,14 +1,14 @@ /* - Copyright (C) Dean Camera, 2010. + Copyright (C) Dean Camera, 2011. dean [at] fourwalledcubicle [dot] com - www.fourwalledcubicle.com + www.lufa-lib.org */ #include "TWI.h" -bool TWI_StartTransmission(const uint8_t SlaveAddress, - const uint8_t TimeoutMS) +uint8_t TWI_StartTransmission(const uint8_t SlaveAddress, + const uint8_t TimeoutMS) { for (;;) { @@ -33,17 +33,17 @@ bool TWI_StartTransmission(const uint8_t SlaveAddress, continue; default: TWCR = (1 << TWEN); - return false; + return TWI_ERROR_BusFault; } } _delay_us(10); } - if (!(BusCaptured)) + if (!(TimeoutRemaining)) { TWCR = (1 << TWEN); - return false; + return TWI_ERROR_BusCaptureTimeout; } TWDR = SlaveAddress; @@ -59,17 +59,85 @@ bool TWI_StartTransmission(const uint8_t SlaveAddress, } if (!(TimeoutRemaining)) - return false; + return TWI_ERROR_SlaveResponseTimeout; switch (TWSR & TW_STATUS_MASK) { case TW_MT_SLA_ACK: case TW_MR_SLA_ACK: - return true; + return TWI_ERROR_NoError; default: TWCR = ((1 << TWINT) | (1 << TWSTO) | (1 << TWEN)); - return false; + return TWI_ERROR_SlaveNotReady; + } + } +} + +uint8_t TWI_ReadPacket(const uint8_t SlaveAddress, + const uint8_t TimeoutMS, + const uint8_t* InternalAddress, + 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) + { + while (Length--) + { + if (!(TWI_ReceiveByte(Buffer++, (Length == 0)))) + { + ErrorCode = TWI_ERROR_SlaveNAK; + break; + } } + + TWI_StopTransmission(); } + + return ErrorCode; } +uint8_t TWI_WritePacket(const uint8_t SlaveAddress, + const uint8_t TimeoutMS, + const uint8_t* InternalAddress, + uint8_t InternalAddressLen, + const uint8_t* Buffer, + uint8_t Length) +{ + uint8_t ErrorCode; + + if ((ErrorCode = TWI_StartTransmission((SlaveAddress & TWI_DEVICE_ADDRESS_MASK) | TWI_ADDRESS_WRITE, + TimeoutMS)) == TWI_ERROR_NoError) + { + while (InternalAddressLen--) + { + if (!(TWI_SendByte(*(InternalAddress++)))) + { + ErrorCode = TWI_ERROR_SlaveNAK; + break; + } + } + + while (Length--) + { + if (!(TWI_SendByte(*(Buffer++)))) + { + ErrorCode = TWI_ERROR_SlaveNAK; + break; + } + } + + TWI_StopTransmission(); + } + + return ErrorCode; +}