Begin work to convert embedded-creations USBaspLoader-tiny85 port to bootloadHID

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+USBaspLoader-tiny85 is a modification to the USBaspLoader project giving 
+support for the ATtiny85 microcontroller.  This is a signification modification
+as the tiny85 has very limited boot loader support in the hardware.  The 
+boot loader becomes a part of the application it has loaded by taking over the
+application's reset and USB-related interrupt vectors, yet the application 
+does not need to be modified to support the boot loader.  The boot loader does
+take up more flash (about 2.8k) than the standard USBaspLoader (about 2k), so
+the space available for the application is smaller.
+
+
+WORKING WITH THE BOOT LOADER
+============================
+Because of the limited pin count on the tiny85, the boot loader doesn't look
+for an external condition to enter boot loader mode, it does it automatically
+before starting the application.  On reset the boot loader enumerates with the PC
+as a USBasp programmer, and jumps to the application after 5 seconds if there are
+no USBasp commands sent by the PC.  You can flash the device with AVRDUDE 
+through a "virtual" USBasp programmer. If there is no valid application loaded
+(determined by verifying a checksum calculation across application program space)
+the boot loader will stay connected as a USBasp programmer until the flash is 
+written.
+
+
+HARDWARE CONFIGURATIONS
+=======================
+Even through the ATtiny85 only has 6 IO pins, there are a couple ways designers have 
+connected the USB signals to the tiny85.  
+
+Configuration 1
+The first configuration this bootloader supported was the configuration used by the 
+V-USB example "EasyLogger", and by Sparkfun in their AVR Stick: D- is connected to PB0
+and D+ is connected to PB2 (INT0).  This is convenient as INT0 can be used for USB, 
+and the Pin Change interrupts can be left free for the application to use, but 
+inconvienient as INT0 shares the same pin as USCK/SCL preventing use of the USI peripheral 
+in SPI or I2C mode.  Also, PB0 is used for MOSI/DI/SDA, preventing use of the USI 
+peripheral in UART mode as well as SPI and I2C.
+
+Configuration 2
+An alternate configuration, used by Little Wire, puts the D+ pin on PB4 and D- on PB3, 
+and uses Pin Change interrupts instead of INT0 for USB.  This allows the USI peripheral
+to be used by the application, but prevents using external interrupts: Pin Change 
+interrupts are used by USB, and INT0 shouldn't be used as it's a higher priority 
+interrupt than Pin Change, and will interfere with USB communication.
+
+(There's a third configuration used by vusbtiny: similar to configuration 2 but with the
+D- and D+ pins swapped.  I don't plan to support that configuration in the precompiled 
+binaries, though it can be generated easily by changing bootloaderconfig.h and recompiling.)
+
+
+For more information on the USBaspLoader-tiny85, please visit the
+following URL:
+
+http://www.embeddded-creations.com
+
+(c) 2012 Louis Beaudoin
+
+Below is the unmodified README file for USBaspLoader:
+
+=========================================================================
+
+This is the README file for USBaspLoader.
+
+USBaspLoader is a USB boot loader for AVR microcontrollers. It can be used on
+all AVRs with at least 2 kB of boot loader section, e.g. the popular ATMega8.
+The firmware is flashed into the upper 2 kB of the flash memory and takes
+control immediately after reset. If a certain hardware condition is met
+(this condition can be configured, e.g. a jumper), the boot loader waits for
+data on the USB interface and loads it into the remaining part of the flash
+memory. If the condition is not met, control is passed to the loaded firmware.
+
+This boot loader is similar to Thomas Fischl's avrusbboot and our own
+bootloadHID, but it requires no separate command line tool to upload the data.
+USBaspLoader emulates Thomas Fischl's USBasp programmer instead. You can thus
+use AVRDUDE to upload flash memory data (and if the option is enabled) EEPROM
+data.
+
+Since USBaspLoader cooperates with AVRDUDE, it can be used in conjunction with
+the Arduino software to upload flash memory data.
+
+
+FILES IN THE DISTRIBUTION
+=========================
+Readme.txt ........ The file you are currently reading.
+firmware .......... Source code of the controller firmware.
+firmware/usbdrv ... USB driver -- See Readme.txt in that directory for info
+License.txt ....... Public license (GPL2) for all contents of this project.
+Changelog.txt ..... Logfile documenting changes in soft-, firm- and hardware.
+
+
+BUILDING AND INSTALLING
+=======================
+This project can be built on Unix (Linux, FreeBSD or Mac OS X) or Windows.
+
+For all platforms, you must first describe your hardware in the file
+"firmware/bootloaderconfig.h". See the documentation in the example provided
+with this distribution for details. Then edit "firmware/Makefile" to reflect
+the target device, the device's boot loader address and fuse bit values.
+
+Building on Windows:
+You need WinAVR for the firmware, see http://winavr.sourceforge.net/.
+To build the firmware with WinAVR, change into the "firmware" directory,
+check whether you need to edit the "Makefile" (e.g. change device settings,
+programmer hardware, clock rate etc.) or bootloaderconfig.h and type "make"
+to compile the source code. Before you upload the code to the device with
+"make flash", you should set the fuses with "make fuse". To protect the boot
+loader from overwriting itself, set the lock bits with "make lock" after
+uploading the firmware.
+
+Building on Unix (Linux, FreeBSD and Mac):
+You need the GNU toolchain and avr-libc for the firmware. See
+    http://www.nongnu.org/avr-libc/user-manual/install_tools.html
+for a good description on how to install the GNU compiler toolchain and
+avr-libc on Unix. For Mac OS X, we provide a read-made package, see
+    http://www.obdev.at/avrmacpack/
+
+To build the firmware, change to the "firmware" directory, edit "Makefile"
+and bootloaderconfig.h as described in the Windows paragraph above and type
+"make" to compile the source code. Before you upload the code to the device
+with "make flash", you should set the fuses with "make fuse". Then protect the
+boot loader firmware with "make lock".
+
+
+WORKING WITH THE BOOT LOADER
+============================
+The boot loader is quite easy to use. Set the jumper (or whatever condition
+you have configured) for boot loading on the target hardware, connect it to
+the host computer and (if not bus powered) issue a Reset on the AVR.
+
+You can now flash the device with AVRDUDE through a "virtual" USBasp
+programmer.
+
+
+USING THE USB DRIVER FOR YOUR OWN PROJECTS
+==========================================
+This project is not intended as a reference implementation. If you want to
+use AVR-USB in your own projects, please see
+   * PowerSwitch for the most basic example,
+   * Automator for an HID example or
+   * AVR-Doper for a very complex example on how to simulate a serial
+     interface (virtual COM port).
+All these projects can be downloaded from http://www.obdev.at/avrusb/
+
+
+ABOUT THE LICENSE
+=================
+It is our intention to make our USB driver and this demo application
+available to everyone. Moreover, we want to make a broad range of USB
+projects and ideas for USB devices available to the general public. We
+therefore want that all projects built with our USB driver are published
+under an Open Source license. Our license for the USB driver and demo code is
+the GNU General Public License Version 2 (GPL2). See the file "License.txt"
+for details.
+
+If you don't want to publish your source code under the GPL2, you can simply
+pay money for AVR-USB. As an additional benefit you get USB PIDs for free,
+licensed exclusively to you. See the file "CommercialLicense.txt" in the usbdrv
+directory for details.
+
+
+MORE INFORMATION
+================
+For more information about Objective Development's firmware-only USB driver
+for Atmel's AVR microcontrollers please visit the URL
+
+    http://www.obdev.at/products/avrusb/
+
+A technical documentation of the driver's interface can be found in the
+file "firmware/usbdrv/usbdrv.h".
+
+
+--
+(c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH.
+http://www.obdev.at/