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AT32UC3A DFU bootloader & freertos

Posted by Manwlis Giannos on July 24, 2007
Hello to all
According to atmel the new newly shipped eval boards EVK11xx are containing AT32UC mcus with preloaded the USB DFU bootloader. The documentation about the bootloader contains guidelines of how can be programmed without the use of JTAGICE MK II. Does the freertos tarball contain special configuration for flashing the mcu without erasing or overlaping the bootloader user space, using the flashing sw tools BatchISP & Flip3? If yes what is the procedure someone must follow?
Thank you in advance.


RE: AT32UC3A DFU bootloader & freertos

Posted by Dave on July 24, 2007
Have you read http://www.freertos.org/a00111.html ?

How the heap is allocated depends on the memory management scheme you include in your makefile. If you are using heap_1 or heap_2 then the "FreeRTOS heap" is just an array from which data is grabed when FreeRTOS wants to create a task or queue. It is not the heap as your compiler knows it. heap_3 is just a wrapper for malloc and free.

The stacks for the tasks come from the "FreeRTOS heap". Task context is saved into this space.

The scheduler uses Supervisor mode stack, but not much. Interrupts use IRQ or FIQ stacks. Nothing uses User mode stack unless you call main in User mode.


RE: AT32UC3A DFU bootloader & freertos

Posted by Dave on July 24, 2007
Replied to the wrong post. Sorry I don't know anything about the AVR32 boot loader. Is it like the SAM-BA on the SAM7?


RE: AT32UC3A DFU bootloader & freertos

Posted by Manwlis Giannos on July 25, 2007
Thanks for your reply Dave. I don't know yet. I'm trying to figure this out in order to proceed on purchase of EVK1100 eval board. I know exactly what is SAM-BA and in a first view resembles to the DFU bootloader but how much...


RE: AT32UC3A DFU bootloader & freertos

Posted by Richard on July 25, 2007
A FreeRTOS.org application is 'just another' application with no special requirements that I know of regarding bootloaders. Just to check I passed your question on to one of the Atmel guys, and here is his response:

"Yes, there is no difference whether the application uses FreeRTOS or
not. The FreeRTOS makefiles can program the flash using the bootloader.
For that, uses the following command:
make isp program run

Here is a doc on the bootloader:


RE: AT32UC3A DFU bootloader & freertos

Posted by Manwlis Giannos on July 26, 2007
Thanks Richard for the reply. 1 last question if you know. "Flashing" with the "isp" procedure needs only a single USB cable connection or through JTAG or , at last, the JTAGICE device as indicated in "freertos" demo concerning the at32uc3a device located on the evk1100 eval board.

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