TMS320F28035 bootloading to SD card

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The TMS320F28035 microcontroller has limited flash memory (128KB), which poses challenges for larger program binaries exceeding this size. Bootloading from an SD card is possible by configuring the bootmode using GPIO pins, but the boot ROM primarily loads code into on-chip memory, raising questions about running programs directly from the SD card. To set OTP values for bootmode configuration, a program must be written and loaded into flash, with changes persisting after a reset. The program format for the SD card is not strictly defined, allowing the use of binaries generated from Code Composer Studio. Overall, while running programs from SD is complex, understanding the bootloading process and file formats can help navigate these limitations.
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I'm using a TMS320F28035 (TI -piccolo series) microcontroller and it came to my attention that the chip only has about 128KB of flash memory and the binaries for my main program are easily 150KB or larger. So that's where my SD dilemma comes in. The documentation (section 2.1)

http://www.ti.com/lit/ug/sprugo0a/sprugo0a.pdf

shows that it has bootloading software that only needs the TRST line to be low and then specify the bootmode using 2 GPIO pins, I'd be using "GetMode" (section 3.3.9)

http://www.ti.com/lit/ds/sprs584i/sprs584i.pdf

By default Get Mode goes to flash but I can specify the SD interface, one of the serial interfaces I can't remember at the moment probably SPI, by setting the OTP values (OTP_KEY, OTP_BMODE) appropriately. Their locations are given and values necessary as well for the desired bootmode.


My Questions:


1 - The lines that state that "the boot ROM will load code and data into on-chip memory from an external... " makes me think that it simply loads everything it can fit onto flash memory which isn't the entire program. Am I wrong in my assumption if is it possible to run the program from the SD card or does it have to fit in the flash?

2 - In order to set the OTP values, do I have to write a program and load that into the flash and run it to make those changes and will they stick on the next reset ?

3 - Does the program have to be formatted in a special format or can I simply take the binaries generated from Code Composer Studio and drop that onto the SD?

Thanks for any help you can provide
 
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Turns out running the program from the SD is incredibly difficult, but luckily CCS's output file .out under the binaries folder isn't the actual program size.
 
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