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<section>Device Firmware Upgrade</section>
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<para>
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Since the device firmware is Free Software licensed under GNU GPL,
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we encourage and enable users to enhance and adapt the firmware according to
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their needs. In order to really benefit from this freedom, we have embedded
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an easy mechanism to update the device firmware without any special tools /
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adapters / cables / programmers or the like.
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</para>
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<para>
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The OpenPICC implements the USB Device Firmware Upgrade speficication,
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as released by the USB Association. Using this protocol, it is possible to
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update the device firmware via special-purpose USB control requests.
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</para>
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<para>
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A software implementation of the USB DFU host side was already available for
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Linux under the name of "dfu-programmer". However, this program did not
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implement the true standard, but some vendor-specific dialect of it.
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Therefore, dfu-programmer has been enhanced to have full native support
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for standard DFU.
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</para>
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</section> <!-- DFU -->
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<section>Emergency Firmware Flash</section>
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<para>
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The AT91SAM7 microcontroller used in the device contains a USB flash loader
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(called SAM-BA) in read-only memory. By setting a jumper on the PCB and
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powering up the device for 20 seconds, this loader can be copied into the
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first 8kb of flash memory, overwriting the existing content.
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</para>
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<para>
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So if the DFU loader has become inoperable, e.g. because of bugs in
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experimental DFU modifications, SAM-BA can be employed to rescue the system.
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</para>
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<para>
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Apart from proprietary Windows software by Atmel, there's the Free Software
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sam7utils project which provides a host program called 'sam7' to interface
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with SAM-BA and facilitate a full-flash rewrite with DFU and the device firmware.
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</para>
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<para>
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For more information on the flash procedure, we refer to the AT91SAM7 product
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documentation, as well as the sam7utils documentation.
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</para>
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</section> <!-- SAM-BA -->
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