Added support to the AVRISP-MKII project for ISP speeds slower than 125KHz via a new software SPI driver.

Added new SPI_ORDER_* data order masks to the SPI peripheral driver.

11 files changed, 269 insertions, 90 deletions

diff --git a/Demos/Device/ClassDriver/MassStorage/MassStorage.c b/Demos/Device/ClassDriver/MassStorage/MassStorage.c
index f91a998d9..b1ec7d375 100644
--- a/Demos/Device/ClassDriver/MassStorage/MassStorage.c
+++ b/Demos/Device/ClassDriver/MassStorage/MassStorage.c
@@ -87,7 +87,7 @@ void SetupHardware(void)
 
 	/* Hardware Initialization */
 	LEDs_Init();
-	SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_SCK_LEAD_FALLING | SPI_SAMPLE_TRAILING | SPI_MODE_MASTER);
+	SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_ORDER_MSB_FIRST | SPI_SCK_LEAD_FALLING | SPI_SAMPLE_TRAILING | SPI_MODE_MASTER);
 	Dataflash_Init();
 	USB_Init();
 
diff --git a/Demos/Device/ClassDriver/MassStorageKeyboard/MassStorageKeyboard.c b/Demos/Device/ClassDriver/MassStorageKeyboard/MassStorageKeyboard.c
index 2a6e3dd78..4ac5ebde3 100644
--- a/Demos/Device/ClassDriver/MassStorageKeyboard/MassStorageKeyboard.c
+++ b/Demos/Device/ClassDriver/MassStorageKeyboard/MassStorageKeyboard.c
@@ -113,7 +113,7 @@ void SetupHardware(void)
 	LEDs_Init();
 	Joystick_Init();
 	Buttons_Init();
-	SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_SCK_LEAD_FALLING | SPI_SAMPLE_TRAILING | SPI_MODE_MASTER);
+	SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_ORDER_MSB_FIRST | SPI_SCK_LEAD_FALLING | SPI_SAMPLE_TRAILING | SPI_MODE_MASTER);
 	Dataflash_Init();
 	USB_Init();
 
diff --git a/Demos/Device/LowLevel/MassStorage/MassStorage.c b/Demos/Device/LowLevel/MassStorage/MassStorage.c
index 93b7c6102..5b0ab17ca 100644
--- a/Demos/Device/LowLevel/MassStorage/MassStorage.c
+++ b/Demos/Device/LowLevel/MassStorage/MassStorage.c
@@ -76,7 +76,7 @@ void SetupHardware(void)
 
 	/* Hardware Initialization */
 	LEDs_Init();
-	SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_SCK_LEAD_FALLING | SPI_SAMPLE_TRAILING | SPI_MODE_MASTER);
+	SPI_Init(SPI_SPEED_FCPU_DIV_2 | SPI_ORDER_MSB_FIRST | SPI_SCK_LEAD_FALLING | SPI_SAMPLE_TRAILING | SPI_MODE_MASTER);
 	Dataflash_Init();
 	USB_Init();
 
diff --git a/LUFA/Drivers/Peripheral/SPI.h b/LUFA/Drivers/Peripheral/SPI.h
index d66e9fe24..06a8f1880 100644
--- a/LUFA/Drivers/Peripheral/SPI.h
+++ b/LUFA/Drivers/Peripheral/SPI.h
@@ -99,6 +99,15 @@
 
 			/** SPI data sample mode mask for SPI_Init(). Indicates that the data should be sampled on the trailing edge. */
 			#define SPI_SAMPLE_TRAILING            (1 << CPHA)
+
+			/** SPI data order mask for SPI_Init(). Indicates that data should be shifted out MSB first. */
+			#define SPI_ORDER_MSB_FIRST            (0 << DORD)
+
+			/** SPI data order mask for SPI_Init(). Indicates that data should be shifted out MSB first. */
+			#define SPI_ORDER_LSB_FIRST            (1 << DORD)
+
+			/** SPI data sample mode mask for SPI_Init(). Indicates that the data should be sampled on the trailing edge. */
+			#define SPI_SAMPLE_TRAILING            (1 << CPHA)
 			
 			/** SPI mode mask for SPI_Init(). Indicates that the SPI interface should be initialized into slave mode. */
 			#define SPI_MODE_SLAVE                 (0 << MSTR)
@@ -111,7 +120,7 @@
 			 *  SPI routines.
 			 *
 			 *  \param[in] SPIOptions  SPI Options, a mask consisting of one of each of the SPI_SPEED_*,
-			 *                         SPI_SCK_*, SPI_SAMPLE_* and SPI_MODE_* masks.
+			 *                         SPI_SCK_*, SPI_SAMPLE_*, SPI_ORDER_* and SPI_MODE_* masks.
 			 */
 			static inline void SPI_Init(const uint8_t SPIOptions)
 			{
diff --git a/LUFA/ManPages/ChangeLog.txt b/LUFA/ManPages/ChangeLog.txt
index c4f0f9401..2e8496e30 100644
--- a/LUFA/ManPages/ChangeLog.txt
+++ b/LUFA/ManPages/ChangeLog.txt
@@ -18,6 +18,8 @@
   *  - Added ability to set the serial baud rate via the user's terminal in the XPLAINBridge project
   *  - Added new LUFA module variables for the different source modules in the core library makefile to simplify project makefiles
   *  - Added start of a new Test and Measurement class demo (thanks to Peter Lawrence)
+  *  - Added new SPI_ORDER_* data order masks to the SPI peripheral driver
+  *  - Added support to the AVRISP-MKII project for ISP speeds slower than 125KHz via a new software SPI driver
   *
   *  <b>Changed:</b>
   *  - The RingBuff library code has been replaced in the XPLAINBridge, Benito and USBtoSerial projects with an ultra lightweight
diff --git a/Projects/AVRISP-MKII/AVRISP-MKII.txt b/Projects/AVRISP-MKII/AVRISP-MKII.txt
index 519a49c7a..15c2dab62 100644
--- a/Projects/AVRISP-MKII/AVRISP-MKII.txt
+++ b/Projects/AVRISP-MKII/AVRISP-MKII.txt
@@ -54,7 +54,6 @@
  *  drivers. When prompted, direct your OS to install Atmel's AVRISP-MKII drivers provided with AVRStudio.
  *
  *  Note that this design currently has the following limitations:
- *    - Minimum ISP target clock speed of 500KHz due to hardware SPI module prescaler limitations
  *    - No reversed/shorted target connector detection and notification
  *    - A seperate header is required for each of the ISP, PDI and TPI programming protocols that the user wishes to use
  *
diff --git a/Projects/AVRISP-MKII/Lib/ISP/ISPProtocol.c b/Projects/AVRISP-MKII/Lib/ISP/ISPProtocol.c
index d6e02fa2b..e8423f467 100644
--- a/Projects/AVRISP-MKII/Lib/ISP/ISPProtocol.c
+++ b/Projects/AVRISP-MKII/Lib/ISP/ISPProtocol.c
@@ -72,7 +72,7 @@ void ISPProtocol_EnterISPMode(void)
 
 	/* Perform execution delay, initialize SPI bus */
 	ISPProtocol_DelayMS(Enter_ISP_Params.ExecutionDelayMS); 
-	SPI_Init(ISPTarget_GetSPIPrescalerMask() | SPI_SCK_LEAD_RISING | SPI_SAMPLE_LEADING | SPI_MODE_MASTER);
+	ISPTarget_Init();
 
 	/* Continuously attempt to synchronize with the target until either the number of attempts specified
 	 * by the host has exceeded, or the the device sends back the expected response values */
@@ -86,7 +86,7 @@ void ISPProtocol_EnterISPMode(void)
 		for (uint8_t RByte = 0; RByte < sizeof(ResponseBytes); RByte++)
 		{
 			ISPProtocol_DelayMS(Enter_ISP_Params.ByteDelay);
-			ResponseBytes[RByte] = SPI_TransferByte(Enter_ISP_Params.EnterProgBytes[RByte]);
+			ResponseBytes[RByte] = ISPTarget_TransferByte(Enter_ISP_Params.EnterProgBytes[RByte]);
 		}
 		
 		/* Check if polling disabled, or if the polled value matches the expected value */
@@ -124,7 +124,7 @@ void ISPProtocol_LeaveISPMode(void)
 	/* Perform pre-exit delay, release the target /RESET, disable the SPI bus and perform the post-exit delay */
 	ISPProtocol_DelayMS(Leave_ISP_Params.PreDelayMS);
 	ISPTarget_ChangeTargetResetLine(false);
-	SPI_ShutDown();
+	ISPTarget_ShutDown();
 	ISPProtocol_DelayMS(Leave_ISP_Params.PostDelayMS);
 
 	/* Turn off the synchronous USART to terminate the recovery clock on XCK pin */
@@ -204,10 +204,10 @@ void ISPProtocol_ProgramMemory(uint8_t V2Command)
 			bool    IsOddByte   = (CurrentByte & 0x01);
 			uint8_t ByteToWrite = *(NextWriteByte++);
 		
-			SPI_SendByte(Write_Memory_Params.ProgrammingCommands[0]);
-			SPI_SendByte(CurrentAddress >> 8);
-			SPI_SendByte(CurrentAddress & 0xFF);
-			SPI_SendByte(ByteToWrite);
+			ISPTarget_SendByte(Write_Memory_Params.ProgrammingCommands[0]);
+			ISPTarget_SendByte(CurrentAddress >> 8);
+			ISPTarget_SendByte(CurrentAddress & 0xFF);
+			ISPTarget_SendByte(ByteToWrite);
 			
 			/* AVR FLASH addressing requires us to modify the write command based on if we are writing a high
 			 * or low byte at the current word address */
@@ -231,10 +231,10 @@ void ISPProtocol_ProgramMemory(uint8_t V2Command)
 		/* If the current page must be committed, send the PROGRAM PAGE command to the target */
 		if (Write_Memory_Params.ProgrammingMode & PROG_MODE_COMMIT_PAGE_MASK)
 		{
-			SPI_SendByte(Write_Memory_Params.ProgrammingCommands[1]);
-			SPI_SendByte(StartAddress >> 8);
-			SPI_SendByte(StartAddress & 0xFF);
-			SPI_SendByte(0x00);
+			ISPTarget_SendByte(Write_Memory_Params.ProgrammingCommands[1]);
+			ISPTarget_SendByte(StartAddress >> 8);
+			ISPTarget_SendByte(StartAddress & 0xFF);
+			ISPTarget_SendByte(0x00);
 			
 			/* Check if polling is possible, if not switch to timed delay mode */
 			if (!(PollAddress))
@@ -266,10 +266,10 @@ void ISPProtocol_ProgramMemory(uint8_t V2Command)
 				MustLoadExtendedAddress = false;
 			}
 
-			SPI_SendByte(Write_Memory_Params.ProgrammingCommands[0]);
-			SPI_SendByte(CurrentAddress >> 8);
-			SPI_SendByte(CurrentAddress & 0xFF);
-			SPI_SendByte(ByteToWrite);
+			ISPTarget_SendByte(Write_Memory_Params.ProgrammingCommands[0]);
+			ISPTarget_SendByte(CurrentAddress >> 8);
+			ISPTarget_SendByte(CurrentAddress & 0xFF);
+			ISPTarget_SendByte(ByteToWrite);
 			
 			/* AVR FLASH addressing requires us to modify the write command based on if we are writing a high
 			 * or low byte at the current word address */
@@ -343,10 +343,10 @@ void ISPProtocol_ReadMemory(uint8_t V2Command)
 		}
 
 		/* Read the next byte from the desired memory space in the device */
-		SPI_SendByte(Read_Memory_Params.ReadMemoryCommand);
-		SPI_SendByte(CurrentAddress >> 8);
-		SPI_SendByte(CurrentAddress & 0xFF);
-		Endpoint_Write_Byte(SPI_ReceiveByte());
+		ISPTarget_SendByte(Read_Memory_Params.ReadMemoryCommand);
+		ISPTarget_SendByte(CurrentAddress >> 8);
+		ISPTarget_SendByte(CurrentAddress & 0xFF);
+		Endpoint_Write_Byte(ISPTarget_ReceiveByte());
 		
 		/* Check if the endpoint bank is currently full, if so send the packet */
 		if (!(Endpoint_IsReadWriteAllowed()))
@@ -406,7 +406,7 @@ void ISPProtocol_ChipErase(void)
 	
 	/* Send the chip erase commands as given by the host to the device */
 	for (uint8_t SByte = 0; SByte < sizeof(Erase_Chip_Params.EraseCommandBytes); SByte++)
-	  SPI_SendByte(Erase_Chip_Params.EraseCommandBytes[SByte]);
+	  ISPTarget_SendByte(Erase_Chip_Params.EraseCommandBytes[SByte]);
 
 	/* Use appropriate command completion check as given by the host (delay or busy polling) */
 	if (!(Erase_Chip_Params.PollMethod))
@@ -442,7 +442,7 @@ void ISPProtocol_ReadFuseLockSigOSCCAL(uint8_t V2Command)
 
 	/* Send the Fuse or Lock byte read commands as given by the host to the device, store response */
 	for (uint8_t RByte = 0; RByte < sizeof(ResponseBytes); RByte++)
-	  ResponseBytes[RByte] = SPI_TransferByte(Read_FuseLockSigOSCCAL_Params.ReadCommandBytes[RByte]);
+	  ResponseBytes[RByte] = ISPTarget_TransferByte(Read_FuseLockSigOSCCAL_Params.ReadCommandBytes[RByte]);
 		
 	Endpoint_Write_Byte(V2Command);
 	Endpoint_Write_Byte(STATUS_CMD_OK);
@@ -471,7 +471,7 @@ void ISPProtocol_WriteFuseLock(uint8_t V2Command)
 
 	/* Send the Fuse or Lock byte program commands as given by the host to the device */
 	for (uint8_t SByte = 0; SByte < sizeof(Write_FuseLockSig_Params.WriteCommandBytes); SByte++)
-	  SPI_SendByte(Write_FuseLockSig_Params.WriteCommandBytes[SByte]);
+	  ISPTarget_SendByte(Write_FuseLockSig_Params.WriteCommandBytes[SByte]);
 		
 	Endpoint_Write_Byte(V2Command);
 	Endpoint_Write_Byte(STATUS_CMD_OK);
@@ -507,9 +507,9 @@ void ISPProtocol_SPIMulti(void)
 	while (CurrTxPos < SPI_Multi_Params.RxStartAddr)
 	{
 		if (CurrTxPos < SPI_Multi_Params.TxBytes)
-		  SPI_SendByte(SPI_Multi_Params.TxData[CurrTxPos]);
+		  ISPTarget_SendByte(SPI_Multi_Params.TxData[CurrTxPos]);
 		else
-		  SPI_SendByte(0);
+		  ISPTarget_SendByte(0);
 		
 		CurrTxPos++;
 	}
@@ -518,9 +518,9 @@ void ISPProtocol_SPIMulti(void)
 	while (CurrRxPos < SPI_Multi_Params.RxBytes)
 	{
 		if (CurrTxPos < SPI_Multi_Params.TxBytes)
-		  Endpoint_Write_Byte(SPI_TransferByte(SPI_Multi_Params.TxData[CurrTxPos++]));
+		  Endpoint_Write_Byte(ISPTarget_TransferByte(SPI_Multi_Params.TxData[CurrTxPos++]));
 		else
-		  Endpoint_Write_Byte(SPI_ReceiveByte());
+		  Endpoint_Write_Byte(ISPTarget_ReceiveByte());
 		  
 		/* Check to see if we have filled the endpoint bank and need to send the packet */
 		if (!(Endpoint_IsReadWriteAllowed()))
diff --git a/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.c b/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.c
index 2df8710eb..7c40ff847 100644
--- a/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.c
+++ b/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.c
@@ -37,7 +37,7 @@
 
 #if defined(ENABLE_ISP_PROTOCOL) || defined(__DOXYGEN__)
 
-/** List of SPI prescaler masks for possible AVRStudio ISP programming speeds. */
+/** List of hardware SPI prescaler masks for possible AVRStudio ISP programming speeds. */
 static uint8_t SPIMaskFromSCKDuration[] PROGMEM =
 {
 #if (F_CPU == 8000000)
@@ -61,25 +61,147 @@ static uint8_t SPIMaskFromSCKDuration[] PROGMEM =
 #endif
 };
 
-/** Converts the given AVR Studio SCK duration parameter (set by a SET PARAM command from the host) to the nearest
- *  possible SPI clock prescaler mask for passing to the SPI_Init() routine.
- *
- *  \return Nearest SPI prescaler mask for the given SCK frequency
+/** Lookup table to convert the slower ISP speeds into a compare value for the software SPI driver. */
+static uint16_t TimerCompareFromSCKDuration[] PROGMEM =
+{
+	TIMER_COMP(96386), TIMER_COMP(89888), TIMER_COMP(84211), TIMER_COMP(79208), TIMER_COMP(74767),
+	TIMER_COMP(70797), TIMER_COMP(67227), TIMER_COMP(64000), TIMER_COMP(61069), TIMER_COMP(58395),
+	TIMER_COMP(55945), TIMER_COMP(51613), TIMER_COMP(49690), TIMER_COMP(47905), TIMER_COMP(46243),
+	TIMER_COMP(43244), TIMER_COMP(41885), TIMER_COMP(39409), TIMER_COMP(38278), TIMER_COMP(36200),
+	TIMER_COMP(34335), TIMER_COMP(32654), TIMER_COMP(31129), TIMER_COMP(29740), TIMER_COMP(28470),
+	TIMER_COMP(27304), TIMER_COMP(25724), TIMER_COMP(24768), TIMER_COMP(23461), TIMER_COMP(22285),
+	TIMER_COMP(21221), TIMER_COMP(20254), TIMER_COMP(19371), TIMER_COMP(18562), TIMER_COMP(17583),
+	TIMER_COMP(16914), TIMER_COMP(16097), TIMER_COMP(15356), TIMER_COMP(14520), TIMER_COMP(13914),
+	TIMER_COMP(13224), TIMER_COMP(12599), TIMER_COMP(12031), TIMER_COMP(11511), TIMER_COMP(10944),
+	TIMER_COMP(10431), TIMER_COMP(9963),  TIMER_COMP(9468),  TIMER_COMP(9081),  TIMER_COMP(8612),
+	TIMER_COMP(8239),  TIMER_COMP(7851),  TIMER_COMP(7498),  TIMER_COMP(7137),  TIMER_COMP(6809),
+	TIMER_COMP(6478),  TIMER_COMP(6178),  TIMER_COMP(5879),  TIMER_COMP(5607),  TIMER_COMP(5359),
+	TIMER_COMP(5093),  TIMER_COMP(4870),  TIMER_COMP(4633),  TIMER_COMP(4418),  TIMER_COMP(4209),
+	TIMER_COMP(4019),  TIMER_COMP(3823),  TIMER_COMP(3645),  TIMER_COMP(3474),  TIMER_COMP(3310),
+	TIMER_COMP(3161),  TIMER_COMP(3011),  TIMER_COMP(2869),  TIMER_COMP(2734),  TIMER_COMP(2611),
+	TIMER_COMP(2484),  TIMER_COMP(2369),  TIMER_COMP(2257),  TIMER_COMP(2152),  TIMER_COMP(2052),
+	TIMER_COMP(1956),  TIMER_COMP(1866),  TIMER_COMP(1779),  TIMER_COMP(1695),  TIMER_COMP(1615),
+	TIMER_COMP(1539),  TIMER_COMP(1468),  TIMER_COMP(1398),  TIMER_COMP(1333),  TIMER_COMP(1271),
+	TIMER_COMP(1212),  TIMER_COMP(1155),  TIMER_COMP(1101),  TIMER_COMP(1049),  TIMER_COMP(1000),
+	TIMER_COMP(953),   TIMER_COMP(909),   TIMER_COMP(866),   TIMER_COMP(826),   TIMER_COMP(787),
+	TIMER_COMP(750),   TIMER_COMP(715),   TIMER_COMP(682),   TIMER_COMP(650),   TIMER_COMP(619),
+	TIMER_COMP(590),   TIMER_COMP(563),   TIMER_COMP(536),   TIMER_COMP(511),   TIMER_COMP(487),
+	TIMER_COMP(465),   TIMER_COMP(443),   TIMER_COMP(422),   TIMER_COMP(402),   TIMER_COMP(384),
+	TIMER_COMP(366),   TIMER_COMP(349),   TIMER_COMP(332),   TIMER_COMP(317),   TIMER_COMP(302),
+	TIMER_COMP(288),   TIMER_COMP(274),   TIMER_COMP(261),   TIMER_COMP(249),   TIMER_COMP(238),
+	TIMER_COMP(226),   TIMER_COMP(216),   TIMER_COMP(206),   TIMER_COMP(196),   TIMER_COMP(187),
+	TIMER_COMP(178),   TIMER_COMP(170),   TIMER_COMP(162),   TIMER_COMP(154),   TIMER_COMP(147),
+	TIMER_COMP(140),   TIMER_COMP(134),   TIMER_COMP(128),   TIMER_COMP(122),   TIMER_COMP(116),
+	TIMER_COMP(111),   TIMER_COMP(105),   TIMER_COMP(100),   TIMER_COMP(95.4),  TIMER_COMP(90.9),
+	TIMER_COMP(86.6),  TIMER_COMP(82.6),  TIMER_COMP(78.7),  TIMER_COMP(75.0),  TIMER_COMP(71.5),
+	TIMER_COMP(68.2),  TIMER_COMP(65.0),  TIMER_COMP(61.9),  TIMER_COMP(59.0),  TIMER_COMP(56.3),
+	TIMER_COMP(53.6),  TIMER_COMP(51.1)
+};
+
+/** Currently selected SPI driver, either hardware (for fast ISP speeds) or software (for slower ISP speeds). */
+bool HardwareSPIMode = true;
+
+/** Software SPI data register for sending and receiving */
+volatile uint8_t SoftSPI_Data;
+
+/** Number of bits left to transfer in the software SPI driver */
+volatile uint8_t SoftSPI_BitsRemaining;
+
+
+/** ISR to handle software SPI transmission and reception */
+ISR(TIMER1_COMPA_vect, ISR_BLOCK)
+{
+	if (!(PINB & (1 << 1)))
+	{
+		if (SoftSPI_Data & 0x80)
+		  PORTB |=  (1 << 2);
+		else
+		  PORTB &= ~(1 << 2);
+	}
+	else
+	{
+		SoftSPI_Data <<= 1;
+
+		if (!(SoftSPI_BitsRemaining--))
+		  TCCR1B = 0;
+
+		if (PINB & (1 << 3))
+		  SoftSPI_Data |= 0x01;	
+	}
+
+	PORTB ^= (1 << 1);	
+}
+
+/** Initializes the appropriate SPI driver (hardware or software, depending on the selected ISP speed) ready for
+ *  communication with the attached target.
  */
-uint8_t ISPTarget_GetSPIPrescalerMask(void)
+void ISPTarget_Init(void)
 {
 	uint8_t SCKDuration = V2Params_GetParameterValue(PARAM_SCK_DURATION);
 
-	if (SCKDuration >= sizeof(SPIMaskFromSCKDuration))
-	  SCKDuration = (sizeof(SPIMaskFromSCKDuration) - 1);
-	  
-	return pgm_read_byte(&SPIMaskFromSCKDuration[SCKDuration]);
+	if (SCKDuration < sizeof(SPIMaskFromSCKDuration))
+	{
+		HardwareSPIMode = true;
+
+		SPI_Init(pgm_read_byte(&SPIMaskFromSCKDuration[SCKDuration]) | SPI_ORDER_MSB_FIRST |
+		                       SPI_SCK_LEAD_RISING | SPI_SAMPLE_LEADING | SPI_MODE_MASTER);
+	}
+	else
+	{
+		HardwareSPIMode = false;
+		
+		DDRB  |= ((1 << 1) | (1 << 2));
+		PORTB |= ((1 << 0) | (1 << 3));
+
+		TIMSK1 = (1 << OCIE1A);
+		OCR1A  = pgm_read_word(&TimerCompareFromSCKDuration[SCKDuration - sizeof(SPIMaskFromSCKDuration)]);
+	}
+}
+
+/** Shuts down the current selected SPI driver (hardware or software, depending on the selected ISP speed) so that no
+ *  further communications can occur until the driver is re-initialized.
+ */
+void ISPTarget_ShutDown(void)
+{
+	if (HardwareSPIMode)
+	{
+		SPI_ShutDown();
+	}
+	else
+	{
+		DDRB  &= ~((1 << 1) | (1 << 2));
+		PORTB &= ~((1 << 0) | (1 << 3));	
+	}
+}
+
+/** Sends and receives a single byte of data to and from the attached target via software SPI.
+ *
+ *  \param[in] Byte  Byte of data to send to the attached target
+ *
+ *  \return Received byte of data from the attached target
+ */
+uint8_t ISPTarget_TransferSoftSPIByte(const uint8_t Byte)
+{
+	SoftSPI_Data          = Byte;
+	SoftSPI_BitsRemaining = 8;
+
+	if (SoftSPI_Data & 0x01)
+	  PORTB |=  (1 << 2);
+	else
+	  PORTB &= ~(1 << 2);
+
+	TCNT1  = 0;
+	TCCR1B = ((1 << WGM12) | (1 << CS11));
+	while (SoftSPI_BitsRemaining && TimeoutTicksRemaining);
+	TCCR1B = 0;
+	
+	return SoftSPI_Data;
 }
 
 /** Asserts or deasserts the target's reset line, using the correct polarity as set by the host using a SET PARAM command.
  *  When not asserted, the line is tristated so as not to interfere with normal device operation.
  *
- *  \param[in] ResetTarget Boolean true when the target should be held in reset, false otherwise
+ *  \param[in] ResetTarget  Boolean true when the target should be held in reset, false otherwise
  */
 void ISPTarget_ChangeTargetResetLine(const bool ResetTarget)
 {
@@ -97,14 +219,44 @@ void ISPTarget_ChangeTargetResetLine(const bool ResetTarget)
 	}
 }
 
+/** Waits until the target has completed the last operation, by continuously polling the device's
+ *  BUSY flag until it is cleared, or until the command timeout period has expired.
+ *
+ *  \return V2 Protocol status \ref STATUS_CMD_OK if the no timeout occurred, \ref STATUS_RDY_BSY_TOUT otherwise
+ */
+uint8_t ISPTarget_WaitWhileTargetBusy(void)
+{
+	do
+	{
+		ISPTarget_SendByte(0xF0);
+		ISPTarget_SendByte(0x00);
+		ISPTarget_SendByte(0x00);
+	}
+	while ((ISPTarget_ReceiveByte() & 0x01) && TimeoutTicksRemaining);
+
+	return TimeoutTicksRemaining ? STATUS_CMD_OK : STATUS_RDY_BSY_TOUT;
+}
+
+/** Sends a low-level LOAD EXTENDED ADDRESS command to the target, for addressing of memory beyond the
+ *  64KB boundary. This sends the command with the correct address as indicated by the current address
+ *  pointer variable set by the host when a SET ADDRESS command is issued.
+ */
+void ISPTarget_LoadExtendedAddress(void)
+{
+	ISPTarget_SendByte(LOAD_EXTENDED_ADDRESS_CMD);
+	ISPTarget_SendByte(0x00);
+	ISPTarget_SendByte((CurrentAddress & 0x00FF0000) >> 16);
+	ISPTarget_SendByte(0x00);	
+}
+
 /** Waits until the last issued target memory programming command has completed, via the check mode given and using
  *  the given parameters.
  *
  *  \param[in] ProgrammingMode  Programming mode used and completion check to use, a mask of PROG_MODE_* constants
- *  \param[in] PollAddress  Memory address to poll for completion if polling check mode used
- *  \param[in] PollValue  Poll value to check against if polling check mode used
- *  \param[in] DelayMS  Milliseconds to delay before returning if delay check mode used
- *  \param[in] ReadMemCommand  Device low-level READ MEMORY command to send if value check mode used
+ *  \param[in] PollAddress      Memory address to poll for completion if polling check mode used
+ *  \param[in] PollValue        Poll value to check against if polling check mode used
+ *  \param[in] DelayMS          Milliseconds to delay before returning if delay check mode used
+ *  \param[in] ReadMemCommand   Device low-level READ MEMORY command to send if value check mode used
  *
  *  \return V2 Protocol status \ref STATUS_CMD_OK if the no timeout occurred, \ref STATUS_RDY_BSY_TOUT or
  *          \ref STATUS_CMD_TOUT otherwise
@@ -128,11 +280,11 @@ uint8_t ISPTarget_WaitForProgComplete(const uint8_t ProgrammingMode,
 		case PROG_MODE_PAGED_VALUE_MASK:
 			do
 			{
-				SPI_SendByte(ReadMemCommand);
-				SPI_SendByte(PollAddress >> 8);
-				SPI_SendByte(PollAddress & 0xFF);
+				ISPTarget_SendByte(ReadMemCommand);
+				ISPTarget_SendByte(PollAddress >> 8);
+				ISPTarget_SendByte(PollAddress & 0xFF);
 			}
-			while ((SPI_TransferByte(0x00) == PollValue) && TimeoutTicksRemaining);
+			while ((ISPTarget_TransferByte(0x00) == PollValue) && TimeoutTicksRemaining);
 
 			if (!(TimeoutTicksRemaining))
 			 ProgrammingStatus = STATUS_CMD_TOUT;
@@ -147,34 +299,4 @@ uint8_t ISPTarget_WaitForProgComplete(const uint8_t ProgrammingMode,
 	return ProgrammingStatus;
 }
 
-/** Waits until the target has completed the last operation, by continuously polling the device's
- *  BUSY flag until it is cleared, or until the command timeout period has expired.
- *
- *  \return V2 Protocol status \ref STATUS_CMD_OK if the no timeout occurred, \ref STATUS_RDY_BSY_TOUT otherwise
- */
-uint8_t ISPTarget_WaitWhileTargetBusy(void)
-{
-	do
-	{
-		SPI_SendByte(0xF0);
-		SPI_SendByte(0x00);
-		SPI_SendByte(0x00);
-	}
-	while ((SPI_ReceiveByte() & 0x01) && TimeoutTicksRemaining);
-
-	return TimeoutTicksRemaining ? STATUS_CMD_OK : STATUS_RDY_BSY_TOUT;
-}
-
-/** Sends a low-level LOAD EXTENDED ADDRESS command to the target, for addressing of memory beyond the
- *  64KB boundary. This sends the command with the correct address as indicated by the current address
- *  pointer variable set by the host when a SET ADDRESS command is issued.
- */
-void ISPTarget_LoadExtendedAddress(void)
-{
-	SPI_SendByte(LOAD_EXTENDED_ADDRESS_CMD);
-	SPI_SendByte(0x00);
-	SPI_SendByte((CurrentAddress & 0x00FF0000) >> 16);
-	SPI_SendByte(0x00);	
-}
-
 #endif
diff --git a/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.h b/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.h
index 869e0e58b..967849abd 100644
--- a/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.h
+++ b/Projects/AVRISP-MKII/Lib/ISP/ISPTarget.h
@@ -56,21 +56,68 @@
 		#endif
 
 	/* Macros: */
-		/** Total number of allowable ISP programming speeds supported by the device. */
-		#define TOTAL_ISP_PROGRAMMING_SPEEDS  7
-		
 		/** Low level device command to issue an extended FLASH address, for devices with other 128KB of FLASH. */
 		#define LOAD_EXTENDED_ADDRESS_CMD     0x4D
 		
+		/** Macro to convert an ISP frequency to a number of timer clock cycles for the software SPI driver */
+		#define TIMER_COMP(freq) ((((F_CPU / 8) / freq) / 2) - 1)
+
+	/* External Variables: */
+		extern bool HardwareSPIMode;
+
 	/* Function Prototypes: */
-		uint8_t ISPTarget_GetSPIPrescalerMask(void);
+		void    ISPTarget_Init(void);
+		void    ISPTarget_ShutDown(void);
+		uint8_t ISPTarget_TransferSoftSPIByte(const uint8_t Byte);
 		void    ISPTarget_ChangeTargetResetLine(const bool ResetTarget);
+		uint8_t ISPTarget_WaitWhileTargetBusy(void);
+		void    ISPTarget_LoadExtendedAddress(void);
 		uint8_t ISPTarget_WaitForProgComplete(const uint8_t ProgrammingMode,
 		                                      const uint16_t PollAddress,
 		                                      const uint8_t PollValue,
 		                                      const uint8_t DelayMS,
 		                                      const uint8_t ReadMemCommand);
-		uint8_t ISPTarget_WaitWhileTargetBusy(void);
-		void    ISPTarget_LoadExtendedAddress(void);
+
+	/* Inline Functions: */
+		/** Sends a byte of ISP data to the attached target, using the appropriate SPI hardware or
+		 *  software routines depending on the selected ISP speed.
+		 *
+		 *  \param[in] Byte  Byte of data to send to the attached target
+		 */
+		static inline void ISPTarget_SendByte(const uint8_t Byte)
+		{
+			if (HardwareSPIMode)
+			  SPI_SendByte(Byte);
+			else
+			  ISPTarget_TransferSoftSPIByte(Byte);
+		}
+
+		/** Receives a byte of ISP data from the attached target, using the appropriate
+		 *  SPI hardware or software routines depending on the selected ISP speed.
+		 *
+		 *  \return Received byte of data from the attached target
+		 */
+		static inline uint8_t ISPTarget_ReceiveByte(void)
+		{
+			if (HardwareSPIMode)
+			  return SPI_ReceiveByte();
+			else
+			  return ISPTarget_TransferSoftSPIByte(0x00);
+		}
+
+		/** Sends and receives a byte of ISP data to and from the attached target, using the
+		 *  appropriate SPI hardware or software routines depending on the selected ISP speed.
+		 *
+		 *  \param[in] Byte  Byte of data to send to the attached target
+		 *
+		 *  \return Received byte of data from the attached target
+		 */
+		static inline uint8_t ISPTarget_TransferByte(const uint8_t Byte)
+		{
+			if (HardwareSPIMode)
+			  return SPI_TransferByte(Byte);
+			else
+			  return ISPTarget_TransferSoftSPIByte(Byte);
+		}
 
 #endif
diff --git a/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c b/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c
index 56b18f60a..f4ab2bd69 100644
--- a/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c
+++ b/Projects/AVRISP-MKII/Lib/V2ProtocolParams.c
@@ -68,7 +68,7 @@ static ParameterItem_t ParameterTable[] =
 
 		{ .ParamID          = PARAM_SCK_DURATION,
 		  .ParamPrivileges  = PARAM_PRIV_READ | PARAM_PRIV_WRITE,
-		  .ParamValue       = (TOTAL_ISP_PROGRAMMING_SPEEDS - 1) },
+		  .ParamValue       = 6                                  },
 
 		{ .ParamID          = PARAM_RESET_POLARITY,
 		  .ParamPrivileges  = PARAM_PRIV_WRITE,
diff --git a/Projects/AVRISP-MKII/Lib/XPROG/XPROGProtocol.h b/Projects/AVRISP-MKII/Lib/XPROG/XPROGProtocol.h
index c812578e5..978a5a2ab 100644
--- a/Projects/AVRISP-MKII/Lib/XPROG/XPROGProtocol.h
+++ b/Projects/AVRISP-MKII/Lib/XPROG/XPROGProtocol.h
@@ -98,12 +98,12 @@
 
 		#define XPRG_PARAM_NVMBASE                  0x01
 		#define XPRG_PARAM_EEPPAGESIZE              0x02
-		#define XPRG_PARAM_NVMCMD_REG               0x03 /* Undocumented, Reverse-engineered */
-		#define XPRG_PARAM_NVMCSR_REG               0x04 /* Undocumented, Reverse-engineered */
+		#define XPRG_PARAM_NVMCMD_REG               0x03
+		#define XPRG_PARAM_NVMCSR_REG               0x04
 		
 		#define XPRG_PROTOCOL_PDI                   0x00
 		#define XPRG_PROTOCOL_JTAG                  0x01
-		#define XPRG_PROTOCOL_TPI                   0x02 /* Undocumented, Reverse-engineered */
+		#define XPRG_PROTOCOL_TPI                   0x02
 		
 		#define XPRG_PAGEMODE_WRITE                 (1 << 1)
 		#define XPRG_PAGEMODE_ERASE                 (1 << 0)