I am using a TMDSRM48HDK. I am experimenting to see how I could implement a bootloader wit the dev kit as a proof of concept for our end design. I found the following Wiki information:
http://processors.wiki.ti.com/index.php/RM4x_Hercules_MCU_Bootloader
This led me to the following document (and a few others):
http://www.ti.com/lit/an/spna196/spna196.pdf#page=2&zoom=auto,-100,433
For the record I haven't taken the sample code and attempted to run it yet... I had a few questions first.
- From the Dev Kit Users Guide I can't tell what SPI port the SD Card is on. I see the sample bootloader code uses port 2. Is the SD Card on port 2?
- Looking through the pdf, sample code, and wiki page, I see that the SPI port is set into slave mode. I have limited experience with ARM processors. Does setting this port into slave mode, allow the processor to read from the SD card, or whatever device is on port 2?
- Assuming that being a slave to the SD Card allows for reading, how does the code know what/where to read from the SD Card? Does the hex/out/bin file just need to be present on the card?
- Is the process to bootload off of a USB drive similar, except via USB?
Thank you!
