X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/071e02c6b6b4837fa9cf0b6d4c749994e02638d7..0019fbd1294ccc9ecb0ac4ddb5d8c71efcf9597f:/LUFA/Drivers/Peripheral/TWI.c

diff --git a/LUFA/Drivers/Peripheral/TWI.c b/LUFA/Drivers/Peripheral/TWI.c
index bd6e85384..2f4e4ed42 100644
--- a/LUFA/Drivers/Peripheral/TWI.c
+++ b/LUFA/Drivers/Peripheral/TWI.c
@@ -1,20 +1,21 @@
 /*
-     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(uint8_t SlaveAddress, uint8_t TimeoutMS)
+uint8_t TWI_StartTransmission(const uint8_t SlaveAddress,
+                              const uint8_t TimeoutMS)
 {
 	for (;;)
 	{
 		bool     BusCaptured = false;
 		uint16_t TimeoutRemaining;
 
-		TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));	
+		TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));
 
 		TimeoutRemaining = (TimeoutMS * 100);
 		while (TimeoutRemaining-- && !(BusCaptured))
@@ -28,46 +29,115 @@ bool TWI_StartTransmission(uint8_t SlaveAddress, uint8_t TimeoutMS)
 						BusCaptured = true;
 						break;
 					case TW_MT_ARB_LOST:
-						TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));	
+						TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));
 						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;
 		TWCR = ((1 << TWINT) | (1 << TWEN));
-		
+
 		TimeoutRemaining = (TimeoutMS * 100);
 		while (TimeoutRemaining--)
 		{
 			if (TWCR & (1 << TWINT))
 			  break;
-			  
+
 			_delay_us(10);
 		}
-		
+
 		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;
+}