Implemented on-demand PLL clock generation for the U4, U6 and U7 series USB AVRs...
[pub/USBasp.git] / Bootloaders / CDC / BootloaderCDC.c
index b2a278e..99e0ccb 100644 (file)
@@ -1,21 +1,21 @@
 /*
              LUFA Library
 /*
              LUFA Library
-     Copyright (C) Dean Camera, 2010.
-              
+     Copyright (C) Dean Camera, 2011.
+
   dean [at] fourwalledcubicle [dot] com
   dean [at] fourwalledcubicle [dot] com
-      www.fourwalledcubicle.com
+           www.lufa-lib.org
 */
 
 /*
 */
 
 /*
-  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
 
 
-  Permission to use, copy, modify, distribute, and sell this 
+  Permission to use, copy, modify, distribute, and sell this
   software and its documentation for any purpose is hereby granted
   software and its documentation for any purpose is hereby granted
-  without fee, provided that the above copyright notice appear in 
+  without fee, provided that the above copyright notice appear in
   all copies and that both that the copyright notice and this
   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 
+  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 without specific, written prior permission.
 
   The author disclaim all warranties with regard to this
  *
  *  Main source file for the CDC class bootloader. This file contains the complete bootloader logic.
  */
  *
  *  Main source file for the CDC class bootloader. This file contains the complete bootloader logic.
  */
+
 #define  INCLUDE_FROM_BOOTLOADERCDC_C
 #include "BootloaderCDC.h"
 
 #define  INCLUDE_FROM_BOOTLOADERCDC_C
 #include "BootloaderCDC.h"
 
-/** Line coding options for the virtual serial port. Although the virtual serial port data is never
- *  sent through a physical serial port, the line encoding data must still be read and preserved from
- *  the host, or the host will detect a problem and fail to open the port. This structure contains the
- *  current encoding options, including baud rate, character format, parity mode and total number of 
- *  bits in each data chunk.
+/** Contains the current baud rate and other settings of the first virtual serial port. This must be retained as some
+ *  operating systems will not open the port unless the settings can be set successfully.
  */
  */
-CDC_Line_Coding_t LineCoding = { .BaudRateBPS = 9600,
-                                 .CharFormat  = OneStopBit,
-                                 .ParityType  = Parity_None,
-                                 .DataBits    = 8            };
+static CDC_LineEncoding_t LineEncoding = { .BaudRateBPS = 0,
+                                           .CharFormat  = CDC_LINEENCODING_OneStopBit,
+                                           .ParityType  = CDC_PARITY_None,
+                                           .DataBits    = 8                            };
 
 /** Current address counter. This stores the current address of the FLASH or EEPROM as set by the host,
  *  and is used when reading or writing to the AVRs memory (either FLASH or EEPROM depending on the issued
  *  command.)
  */
 
 /** Current address counter. This stores the current address of the FLASH or EEPROM as set by the host,
  *  and is used when reading or writing to the AVRs memory (either FLASH or EEPROM depending on the issued
  *  command.)
  */
-uint32_t CurrAddress;
+static uint32_t CurrAddress;
 
 /** Flag to indicate if the bootloader should be running, or should exit and allow the application code to run
  *  via a watchdog reset. When cleared the bootloader will exit, starting the watchdog and entering an infinite
  *  loop until the AVR restarts and the application runs.
  */
 
 /** Flag to indicate if the bootloader should be running, or should exit and allow the application code to run
  *  via a watchdog reset. When cleared the bootloader will exit, starting the watchdog and entering an infinite
  *  loop until the AVR restarts and the application runs.
  */
-bool RunBootloader = true;
+static bool RunBootloader = true;
 
 
 
 
-/** Main program entry point. This routine configures the hardware required by the bootloader, then continuously 
+/** Main program entry point. This routine configures the hardware required by the bootloader, then continuously
  *  runs the bootloader processing routine until instructed to soft-exit, or hard-reset via the watchdog to start
  *  the loaded application code.
  */
  *  runs the bootloader processing routine until instructed to soft-exit, or hard-reset via the watchdog to start
  *  the loaded application code.
  */
@@ -77,7 +74,7 @@ int main(void)
                CDC_Task();
                USB_USBTask();
        }
                CDC_Task();
                USB_USBTask();
        }
-       
+
        /* Disconnect from the host - USB interface will be reset later along with the AVR */
        USB_Detach();
 
        /* Disconnect from the host - USB interface will be reset later along with the AVR */
        USB_Detach();
 
@@ -96,11 +93,11 @@ void SetupHardware(void)
 
        /* Disable clock division */
        clock_prescale_set(clock_div_1);
 
        /* Disable clock division */
        clock_prescale_set(clock_div_1);
-       
+
        /* Relocate the interrupt vector table to the bootloader section */
        MCUCR = (1 << IVCE);
        MCUCR = (1 << IVSEL);
        /* Relocate the interrupt vector table to the bootloader section */
        MCUCR = (1 << IVCE);
        MCUCR = (1 << IVSEL);
-       
+
        /* Initialize USB Subsystem */
        USB_Init();
 }
        /* Initialize USB Subsystem */
        USB_Init();
 }
@@ -112,75 +109,60 @@ void EVENT_USB_Device_ConfigurationChanged(void)
 {
        /* Setup CDC Notification, Rx and Tx Endpoints */
        Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPNUM, EP_TYPE_INTERRUPT,
 {
        /* Setup CDC Notification, Rx and Tx Endpoints */
        Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPNUM, EP_TYPE_INTERRUPT,
-                                      ENDPOINT_DIR_IN, CDC_NOTIFICATION_EPSIZE,
+                                  ENDPOINT_DIR_IN, CDC_NOTIFICATION_EPSIZE,
                                   ENDPOINT_BANK_SINGLE);
 
        Endpoint_ConfigureEndpoint(CDC_TX_EPNUM, EP_TYPE_BULK,
                                   ENDPOINT_BANK_SINGLE);
 
        Endpoint_ConfigureEndpoint(CDC_TX_EPNUM, EP_TYPE_BULK,
-                                      ENDPOINT_DIR_IN, CDC_TXRX_EPSIZE,
+                                  ENDPOINT_DIR_IN, CDC_TXRX_EPSIZE,
                                   ENDPOINT_BANK_SINGLE);
 
        Endpoint_ConfigureEndpoint(CDC_RX_EPNUM, EP_TYPE_BULK,
                                   ENDPOINT_BANK_SINGLE);
 
        Endpoint_ConfigureEndpoint(CDC_RX_EPNUM, EP_TYPE_BULK,
-                                      ENDPOINT_DIR_OUT, CDC_TXRX_EPSIZE,
+                                  ENDPOINT_DIR_OUT, CDC_TXRX_EPSIZE,
                                   ENDPOINT_BANK_SINGLE);
 }
 
                                   ENDPOINT_BANK_SINGLE);
 }
 
-/** Event handler for the USB_UnhandledControlRequest event. This is used to catch standard and class specific
- *  control requests that are not handled internally by the USB library, so that they can be handled appropriately
- *  for the application.
+/** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
+ *  the device from the USB host before passing along unhandled control requests to the library for processing
+ *  internally.
  */
  */
-void EVENT_USB_Device_UnhandledControlRequest(void)
+void EVENT_USB_Device_ControlRequest(void)
 {
 {
-       uint8_t* LineCodingData = (uint8_t*)&LineCoding;
+       /* Ignore any requests that aren't directed to the CDC interface */
+       if ((USB_ControlRequest.bmRequestType & (CONTROL_REQTYPE_TYPE | CONTROL_REQTYPE_RECIPIENT)) !=
+           (REQTYPE_CLASS | REQREC_INTERFACE))
+       {
+               return;
+       }
 
        /* Process CDC specific control requests */
        switch (USB_ControlRequest.bRequest)
        {
 
        /* Process CDC specific control requests */
        switch (USB_ControlRequest.bRequest)
        {
-               case REQ_GetLineEncoding:
+               case CDC_REQ_GetLineEncoding:
                        if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
                        {
                                Endpoint_ClearSETUP();
 
                        if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
                        {
                                Endpoint_ClearSETUP();
 
-                               for (uint8_t i = 0; i < sizeof(LineCoding); i++)
-                                 Endpoint_Write_Byte(*(LineCodingData++));     
-                               
-                               Endpoint_ClearIN();
-                               
-                               Endpoint_ClearStatusStage();
-                       }
-                       
-                       break;
-               case REQ_SetLineEncoding:
-                       if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
-                       {
-                               Endpoint_ClearSETUP();
-
-                               while (!(Endpoint_IsOUTReceived()))
-                               {                               
-                                       if (USB_DeviceState == DEVICE_STATE_Unattached)
-                                         return;
-                               }
-                       
-                               for (uint8_t i = 0; i < sizeof(LineCoding); i++)
-                                 *(LineCodingData++) = Endpoint_Read_Byte();
-
+                               /* Write the line coding data to the control endpoint */
+                               Endpoint_Write_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t));
                                Endpoint_ClearOUT();
                                Endpoint_ClearOUT();
-
-                               Endpoint_ClearStatusStage();
                        }
                        }
-       
+
                        break;
                        break;
-               case REQ_SetControlLineState:
+               case CDC_REQ_SetLineEncoding:
                        if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
                        {
                                Endpoint_ClearSETUP();
                        if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
                        {
                                Endpoint_ClearSETUP();
-                               
-                               Endpoint_ClearStatusStage();
+
+                               /* Read the line coding data in from the host into the global struct */
+                               Endpoint_Read_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t));
+                               Endpoint_ClearIN();
                        }
                        }
-       
+
                        break;
        }
 }
 
                        break;
        }
 }
 
+#if !defined(NO_BLOCK_SUPPORT)
 /** Reads or writes a block of EEPROM or FLASH memory to or from the appropriate CDC data endpoint, depending
  *  on the AVR910 protocol command issued.
  *
 /** Reads or writes a block of EEPROM or FLASH memory to or from the appropriate CDC data endpoint, depending
  *  on the AVR910 protocol command issued.
  *
@@ -190,20 +172,20 @@ static void ReadWriteMemoryBlock(const uint8_t Command)
 {
        uint16_t BlockSize;
        char     MemoryType;
 {
        uint16_t BlockSize;
        char     MemoryType;
-       
+
        bool     HighByte = false;
        uint8_t  LowByte  = 0;
        bool     HighByte = false;
        uint8_t  LowByte  = 0;
-       
+
        BlockSize  = (FetchNextCommandByte() << 8);
        BlockSize |=  FetchNextCommandByte();
        BlockSize  = (FetchNextCommandByte() << 8);
        BlockSize |=  FetchNextCommandByte();
-       
+
        MemoryType =  FetchNextCommandByte();
 
        if ((MemoryType != 'E') && (MemoryType != 'F'))
        {
                /* Send error byte back to the host */
                WriteNextResponseByte('?');
        MemoryType =  FetchNextCommandByte();
 
        if ((MemoryType != 'E') && (MemoryType != 'F'))
        {
                /* Send error byte back to the host */
                WriteNextResponseByte('?');
-               
+
                return;
        }
 
                return;
        }
 
@@ -221,23 +203,23 @@ static void ReadWriteMemoryBlock(const uint8_t Command)
                                #if (FLASHEND > 0xFFFF)
                                WriteNextResponseByte(pgm_read_byte_far(CurrAddress | HighByte));
                                #else
                                #if (FLASHEND > 0xFFFF)
                                WriteNextResponseByte(pgm_read_byte_far(CurrAddress | HighByte));
                                #else
-                               WriteNextResponseByte(pgm_read_byte(CurrAddress | HighByte));                                   
+                               WriteNextResponseByte(pgm_read_byte(CurrAddress | HighByte));
                                #endif
                                #endif
-                               
+
                                /* If both bytes in current word have been read, increment the address counter */
                                if (HighByte)
                                  CurrAddress += 2;
                                /* If both bytes in current word have been read, increment the address counter */
                                if (HighByte)
                                  CurrAddress += 2;
-                               
+
                                HighByte = !HighByte;
                        }
                        else
                        {
                                /* Read the next EEPROM byte into the endpoint */
                                HighByte = !HighByte;
                        }
                        else
                        {
                                /* Read the next EEPROM byte into the endpoint */
-                               WriteNextResponseByte(eeprom_read_byte((uint8_t*)(uint16_t)(CurrAddress >> 1)));
+                               WriteNextResponseByte(eeprom_read_byte((uint8_t*)(intptr_t)(CurrAddress >> 1)));
 
                                /* Increment the address counter after use */
                                CurrAddress += 2;
 
                                /* Increment the address counter after use */
                                CurrAddress += 2;
-                       }                       
+                       }
                }
        }
        else
                }
        }
        else
@@ -249,11 +231,11 @@ static void ReadWriteMemoryBlock(const uint8_t Command)
                        boot_page_erase(PageStartAddress);
                        boot_spm_busy_wait();
                }
                        boot_page_erase(PageStartAddress);
                        boot_spm_busy_wait();
                }
-               
+
                while (BlockSize--)
                {
                        if (MemoryType == 'F')
                while (BlockSize--)
                {
                        if (MemoryType == 'F')
-                       {       
+                       {
                                /* If both bytes in current word have been written, increment the address counter */
                                if (HighByte)
                                {
                                /* If both bytes in current word have been written, increment the address counter */
                                if (HighByte)
                                {
@@ -262,20 +244,18 @@ static void ReadWriteMemoryBlock(const uint8_t Command)
 
                                        /* Increment the address counter after use */
                                        CurrAddress += 2;
 
                                        /* Increment the address counter after use */
                                        CurrAddress += 2;
-
-                                       HighByte = false;
                                }
                                else
                                {
                                        LowByte = FetchNextCommandByte();
                                }
                                else
                                {
                                        LowByte = FetchNextCommandByte();
-                               
-                                       HighByte = true;
                                }
                                }
+                               
+                               HighByte = !HighByte;
                        }
                        else
                        {
                                /* Write the next EEPROM byte from the endpoint */
                        }
                        else
                        {
                                /* Write the next EEPROM byte from the endpoint */
-                               eeprom_write_byte((uint8_t*)(uint16_t)(CurrAddress >> 1), FetchNextCommandByte());                                      
+                               eeprom_write_byte((uint8_t*)((intptr_t)(CurrAddress >> 1)), FetchNextCommandByte());
 
                                /* Increment the address counter after use */
                                CurrAddress += 2;
 
                                /* Increment the address counter after use */
                                CurrAddress += 2;
@@ -287,15 +267,16 @@ static void ReadWriteMemoryBlock(const uint8_t Command)
                {
                        /* Commit the flash page to memory */
                        boot_page_write(PageStartAddress);
                {
                        /* Commit the flash page to memory */
                        boot_page_write(PageStartAddress);
-                       
+
                        /* Wait until write operation has completed */
                        boot_spm_busy_wait();
                }
                        /* Wait until write operation has completed */
                        boot_spm_busy_wait();
                }
-       
+
                /* Send response byte back to the host */
                /* Send response byte back to the host */
-               WriteNextResponseByte('\r');            
+               WriteNextResponseByte('\r');
        }
 }
        }
 }
+#endif
 
 /** Retrieves the next byte from the host in the CDC data OUT endpoint, and clears the endpoint bank if needed
  *  to allow reception of the next data packet from the host.
 
 /** Retrieves the next byte from the host in the CDC data OUT endpoint, and clears the endpoint bank if needed
  *  to allow reception of the next data packet from the host.
@@ -306,7 +287,7 @@ static uint8_t FetchNextCommandByte(void)
 {
        /* Select the OUT endpoint so that the next data byte can be read */
        Endpoint_SelectEndpoint(CDC_RX_EPNUM);
 {
        /* Select the OUT endpoint so that the next data byte can be read */
        Endpoint_SelectEndpoint(CDC_RX_EPNUM);
-       
+
        /* If OUT endpoint empty, clear it and wait for the next packet from the host */
        while (!(Endpoint_IsReadWriteAllowed()))
        {
        /* If OUT endpoint empty, clear it and wait for the next packet from the host */
        while (!(Endpoint_IsReadWriteAllowed()))
        {
@@ -318,7 +299,7 @@ static uint8_t FetchNextCommandByte(void)
                          return 0;
                }
        }
                          return 0;
                }
        }
-       
+
        /* Fetch the next byte from the OUT endpoint */
        return Endpoint_Read_Byte();
 }
        /* Fetch the next byte from the OUT endpoint */
        return Endpoint_Read_Byte();
 }
@@ -332,20 +313,20 @@ static void WriteNextResponseByte(const uint8_t Response)
 {
        /* Select the IN endpoint so that the next data byte can be written */
        Endpoint_SelectEndpoint(CDC_TX_EPNUM);
 {
        /* Select the IN endpoint so that the next data byte can be written */
        Endpoint_SelectEndpoint(CDC_TX_EPNUM);
-       
+
        /* If IN endpoint full, clear it and wait until ready for the next packet to the host */
        if (!(Endpoint_IsReadWriteAllowed()))
        {
                Endpoint_ClearIN();
        /* If IN endpoint full, clear it and wait until ready for the next packet to the host */
        if (!(Endpoint_IsReadWriteAllowed()))
        {
                Endpoint_ClearIN();
-               
+
                while (!(Endpoint_IsINReady()))
                while (!(Endpoint_IsINReady()))
-               {                               
+               {
                        if (USB_DeviceState == DEVICE_STATE_Unattached)
                          return;
                }
        }
                        if (USB_DeviceState == DEVICE_STATE_Unattached)
                          return;
                }
        }
-       
-       /* Write the next byte to the OUT endpoint */
+
+       /* Write the next byte to the IN endpoint */
        Endpoint_Write_Byte(Response);
 }
 
        Endpoint_Write_Byte(Response);
 }
 
@@ -356,221 +337,232 @@ void CDC_Task(void)
 {
        /* Select the OUT endpoint */
        Endpoint_SelectEndpoint(CDC_RX_EPNUM);
 {
        /* Select the OUT endpoint */
        Endpoint_SelectEndpoint(CDC_RX_EPNUM);
-       
+
        /* Check if endpoint has a command in it sent from the host */
        /* Check if endpoint has a command in it sent from the host */
-       if (Endpoint_IsOUTReceived())
-       {
-               /* Read in the bootloader command (first byte sent from host) */
-               uint8_t Command = FetchNextCommandByte();
+       if (!(Endpoint_IsOUTReceived()))
+         return;
 
 
-               if ((Command == 'L') || (Command == 'P') || (Command == 'T') || (Command == 'E'))
-               {
-                       if (Command == 'E')
-                         RunBootloader = false;
-                       if (Command == 'T')
-                         FetchNextCommandByte();
+       /* Read in the bootloader command (first byte sent from host) */
+       uint8_t Command = FetchNextCommandByte();
 
 
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');                    
-               }
-               else if (Command == 't')
-               {
-                       /* Return ATMEGA128 part code - this is only to allow AVRProg to use the bootloader */
-                       WriteNextResponseByte(0x44);
+       if (Command == 'E')
+       {
+               RunBootloader = false;
+       
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 'T')
+       {
+               FetchNextCommandByte();
 
 
-                       WriteNextResponseByte(0x00);
-               }
-               else if (Command == 'a')
-               {
-                       /* Indicate auto-address increment is supported */
-                       WriteNextResponseByte('Y');
-               }
-               else if (Command == 'A')
-               {
-                       /* Set the current address to that given by the host */
-                       CurrAddress   = (FetchNextCommandByte() << 9);
-                       CurrAddress  |= (FetchNextCommandByte() << 1);
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if ((Command == 'L') || (Command == 'P'))
+       {
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 't')
+       {
+               /* Return ATMEGA128 part code - this is only to allow AVRProg to use the bootloader */
+               WriteNextResponseByte(0x44);
+               WriteNextResponseByte(0x00);
+       }
+       else if (Command == 'a')
+       {
+               /* Indicate auto-address increment is supported */
+               WriteNextResponseByte('Y');
+       }
+       else if (Command == 'A')
+       {
+               /* Set the current address to that given by the host */
+               CurrAddress   = (FetchNextCommandByte() << 9);
+               CurrAddress  |= (FetchNextCommandByte() << 1);
 
 
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');
-               }
-               else if (Command == 'p')
-               {
-                       /* Indicate serial programmer back to the host */
-                       WriteNextResponseByte('S');              
-               }
-               else if (Command == 'S')
-               {
-                       /* Write the 7-byte software identifier to the endpoint */
-                       for (uint8_t CurrByte = 0; CurrByte < 7; CurrByte++)
-                         WriteNextResponseByte(SOFTWARE_IDENTIFIER[CurrByte]);         
-               }
-               else if (Command == 'V')
-               {
-                       WriteNextResponseByte('0' + BOOTLOADER_VERSION_MAJOR);
-                       WriteNextResponseByte('0' + BOOTLOADER_VERSION_MINOR);
-               }
-               else if (Command == 's')
-               {
-                       WriteNextResponseByte(AVR_SIGNATURE_3);         
-                       WriteNextResponseByte(AVR_SIGNATURE_2);
-                       WriteNextResponseByte(AVR_SIGNATURE_1);
-               }
-               else if (Command == 'b')
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 'p')
+       {
+               /* Indicate serial programmer back to the host */
+               WriteNextResponseByte('S');
+       }
+       else if (Command == 'S')
+       {
+               /* Write the 7-byte software identifier to the endpoint */
+               for (uint8_t CurrByte = 0; CurrByte < 7; CurrByte++)
+                 WriteNextResponseByte(SOFTWARE_IDENTIFIER[CurrByte]);
+       }
+       else if (Command == 'V')
+       {
+               WriteNextResponseByte('0' + BOOTLOADER_VERSION_MAJOR);
+               WriteNextResponseByte('0' + BOOTLOADER_VERSION_MINOR);
+       }
+       else if (Command == 's')
+       {
+               WriteNextResponseByte(AVR_SIGNATURE_3);
+               WriteNextResponseByte(AVR_SIGNATURE_2);
+               WriteNextResponseByte(AVR_SIGNATURE_1);
+       }
+       else if (Command == 'e')
+       {
+               /* Clear the application section of flash */
+               for (uint32_t CurrFlashAddress = 0; CurrFlashAddress < BOOT_START_ADDR; CurrFlashAddress += SPM_PAGESIZE)
                {
                {
-                       WriteNextResponseByte('Y');
-                               
-                       /* Send block size to the host */
-                       WriteNextResponseByte(SPM_PAGESIZE >> 8);
-                       WriteNextResponseByte(SPM_PAGESIZE & 0xFF);             
+                       boot_page_erase(CurrFlashAddress);
+                       boot_spm_busy_wait();
+                       boot_page_write(CurrFlashAddress);
+                       boot_spm_busy_wait();
                }
                }
-               else if (Command == 'e')
-               {
-                       /* Clear the application section of flash */
-                       for (uint32_t CurrFlashAddress = 0; CurrFlashAddress < BOOT_START_ADDR; CurrFlashAddress++)
-                       {
-                               boot_page_erase(CurrFlashAddress);
-                               boot_spm_busy_wait();
-                               boot_page_write(CurrFlashAddress);
-                               boot_spm_busy_wait();
 
 
-                               CurrFlashAddress += SPM_PAGESIZE;
-                       }
-                       
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');            
-               }
-               else if (Command == 'l')
-               {
-                       /* Set the lock bits to those given by the host */
-                       boot_lock_bits_set(FetchNextCommandByte());
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       #if !defined(NO_LOCK_BYTE_WRITE_SUPPORT)
+       else if (Command == 'l')
+       {
+               /* Set the lock bits to those given by the host */
+               boot_lock_bits_set(FetchNextCommandByte());
 
 
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');
-               }
-               else if (Command == 'r')
-               {
-                       WriteNextResponseByte(boot_lock_fuse_bits_get(GET_LOCK_BITS));          
-               }
-               else if (Command == 'F')
-               {
-                       WriteNextResponseByte(boot_lock_fuse_bits_get(GET_LOW_FUSE_BITS));
-               }
-               else if (Command == 'N')
-               {
-                       WriteNextResponseByte(boot_lock_fuse_bits_get(GET_HIGH_FUSE_BITS));             
-               }
-               else if (Command == 'Q')
-               {
-                       WriteNextResponseByte(boot_lock_fuse_bits_get(GET_EXTENDED_FUSE_BITS));         
-               }
-               else if (Command == 'C')
-               {                       
-                       /* Write the high byte to the current flash page */
-                       boot_page_fill(CurrAddress, FetchNextCommandByte());
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       #endif
+       else if (Command == 'r')
+       {
+               WriteNextResponseByte(boot_lock_fuse_bits_get(GET_LOCK_BITS));
+       }
+       else if (Command == 'F')
+       {
+               WriteNextResponseByte(boot_lock_fuse_bits_get(GET_LOW_FUSE_BITS));
+       }
+       else if (Command == 'N')
+       {
+               WriteNextResponseByte(boot_lock_fuse_bits_get(GET_HIGH_FUSE_BITS));
+       }
+       else if (Command == 'Q')
+       {
+               WriteNextResponseByte(boot_lock_fuse_bits_get(GET_EXTENDED_FUSE_BITS));
+       }
+       #if !defined(NO_BLOCK_SUPPORT)
+       else if (Command == 'b')
+       {
+               WriteNextResponseByte('Y');
 
 
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');            
-               }
-               else if (Command == 'c')
-               {                       
-                       /* Write the low byte to the current flash page */
-                       boot_page_fill(CurrAddress | 1, FetchNextCommandByte());
-                       
-                       /* Increment the address */
-                       CurrAddress += 2;
-
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');            
-               }
-               else if (Command == 'm')
-               {
-                       /* Commit the flash page to memory */
-                       boot_page_write(CurrAddress);
-                       
-                       /* Wait until write operation has completed */
-                       boot_spm_busy_wait();
+               /* Send block size to the host */
+               WriteNextResponseByte(SPM_PAGESIZE >> 8);
+               WriteNextResponseByte(SPM_PAGESIZE & 0xFF);
+       }
+       else if ((Command == 'B') || (Command == 'g'))
+       {
+               /* Delegate the block write/read to a separate function for clarity */
+               ReadWriteMemoryBlock(Command);
+       }
+       #endif
+       #if !defined(NO_FLASH_BYTE_SUPPORT)
+       else if (Command == 'C')
+       {
+               /* Write the high byte to the current flash page */
+               boot_page_fill(CurrAddress, FetchNextCommandByte());
 
 
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');            
-               }
-               else if ((Command == 'B') || (Command == 'g'))
-               {
-                       /* Delegate the block write/read to a separate function for clarity */
-                       ReadWriteMemoryBlock(Command);
-               }
-               else if (Command == 'R')
-               {
-                       #if (FLASHEND > 0xFFFF)
-                       uint16_t ProgramWord = pgm_read_word_far(CurrAddress);
-                       #else
-                       uint16_t ProgramWord = pgm_read_word(CurrAddress);                      
-                       #endif
-                       
-                       WriteNextResponseByte(ProgramWord >> 8);
-                       WriteNextResponseByte(ProgramWord & 0xFF);
-               }
-               else if (Command == 'D')
-               {
-                       /* Read the byte from the endpoint and write it to the EEPROM */
-                       eeprom_write_byte((uint8_t*)((uint16_t)(CurrAddress >> 1)), FetchNextCommandByte());
-                       
-                       /* Increment the address after use */                   
-                       CurrAddress += 2;
-       
-                       /* Send confirmation byte back to the host */
-                       WriteNextResponseByte('\r');            
-               }
-               else if (Command == 'd')
-               {
-                       /* Read the EEPROM byte and write it to the endpoint */
-                       WriteNextResponseByte(eeprom_read_byte((uint8_t*)((uint16_t)(CurrAddress >> 1))));
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 'c')
+       {
+               /* Write the low byte to the current flash page */
+               boot_page_fill(CurrAddress | 0x01, FetchNextCommandByte());
 
 
-                       /* Increment the address after use */
-                       CurrAddress += 2;
-               }
-               else if (Command == 27)
-               {
-                       /* Escape is sync, ignore */
-               }
-               else
-               {
-                       /* Unknown command, return fail code */
-                       WriteNextResponseByte('?');
-               }
+               /* Increment the address */
+               CurrAddress += 2;
 
 
-               /* Select the IN endpoint */
-               Endpoint_SelectEndpoint(CDC_TX_EPNUM);
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 'm')
+       {
+               /* Commit the flash page to memory */
+               boot_page_write(CurrAddress);
 
 
-               /* Remember if the endpoint is completely full before clearing it */
-               bool IsEndpointFull = !(Endpoint_IsReadWriteAllowed());
+               /* Wait until write operation has completed */
+               boot_spm_busy_wait();
 
 
-               /* Send the endpoint data to the host */
-               Endpoint_ClearIN();
-               
-               /* If a full endpoint's worth of data was sent, we need to send an empty packet afterwards to signal end of transfer */
-               if (IsEndpointFull)
-               {
-                       while (!(Endpoint_IsINReady()))
-                       {                               
-                               if (USB_DeviceState == DEVICE_STATE_Unattached)
-                                 return;
-                       }
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 'R')
+       {
+               #if (FLASHEND > 0xFFFF)
+               uint16_t ProgramWord = pgm_read_word_far(CurrAddress);
+               #else
+               uint16_t ProgramWord = pgm_read_word(CurrAddress);
+               #endif
+
+               WriteNextResponseByte(ProgramWord >> 8);
+               WriteNextResponseByte(ProgramWord & 0xFF);
+       }
+       #endif
+       #if !defined(NO_EEPROM_BYTE_SUPPORT)
+       else if (Command == 'D')
+       {
+               /* Read the byte from the endpoint and write it to the EEPROM */
+               eeprom_write_byte((uint8_t*)((intptr_t)(CurrAddress >> 1)), FetchNextCommandByte());
 
 
-                       Endpoint_ClearIN();
-               }
+               /* Increment the address after use */
+               CurrAddress += 2;
 
 
-               /* Wait until the data has been sent to the host */
+               /* Send confirmation byte back to the host */
+               WriteNextResponseByte('\r');
+       }
+       else if (Command == 'd')
+       {
+               /* Read the EEPROM byte and write it to the endpoint */
+               WriteNextResponseByte(eeprom_read_byte((uint8_t*)((intptr_t)(CurrAddress >> 1))));
+
+               /* Increment the address after use */
+               CurrAddress += 2;
+       }
+       #endif
+       else if (Command != 27)
+       {
+               /* Unknown (non-sync) command, return fail code */
+               WriteNextResponseByte('?');
+       }
+
+       /* Select the IN endpoint */
+       Endpoint_SelectEndpoint(CDC_TX_EPNUM);
+
+       /* Remember if the endpoint is completely full before clearing it */
+       bool IsEndpointFull = !(Endpoint_IsReadWriteAllowed());
+
+       /* Send the endpoint data to the host */
+       Endpoint_ClearIN();
+
+       /* If a full endpoint's worth of data was sent, we need to send an empty packet afterwards to signal end of transfer */
+       if (IsEndpointFull)
+       {
                while (!(Endpoint_IsINReady()))
                while (!(Endpoint_IsINReady()))
-               {                               
+               {
                        if (USB_DeviceState == DEVICE_STATE_Unattached)
                          return;
                }
                        if (USB_DeviceState == DEVICE_STATE_Unattached)
                          return;
                }
-               
-               /* Select the OUT endpoint */
-               Endpoint_SelectEndpoint(CDC_RX_EPNUM);
 
 
-               /* Acknowledge the command from the host */
-               Endpoint_ClearOUT();
+               Endpoint_ClearIN();
+       }
+
+       /* Wait until the data has been sent to the host */
+       while (!(Endpoint_IsINReady()))
+       {
+               if (USB_DeviceState == DEVICE_STATE_Unattached)
+                 return;
        }
        }
+
+       /* Select the OUT endpoint */
+       Endpoint_SelectEndpoint(CDC_RX_EPNUM);
+
+       /* Acknowledge the command from the host */
+       Endpoint_ClearOUT();
 }
 }
+