• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 99 subscribers
  • Views 289 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS320C6748: Boot loader in tms320c6748

nolan
Intellectual 590 points
Part Number: TMS320C6748

Hi,

I want to implement Power on self test (POST) to my  board. From what i have understood  the POST is done during the boot process before it enters the main application.

Here are a few doubts that i have:

1) So if i am to add POST codes how to add it along the boot code which is written by the manufacturer(of course TI) and i think it cant be modified. 

2)  Is the Secondary boot loader  in any way related to the self test routines.

Thanks and Regards,

NOLAN

  • 0
    TI__Guru** 116170 points

    ROM is software that is programmed in the device and only functions to load the initial code from flash/boot media specified using the boot pins. The image on the bootmedia is provided by the user but the ROM code can`t be changed hence the need for secondary bootloaders to allow for customization such as adding power on self tests, etc

    We have seen varies different implementations of Power on self test depending on customer use cases. There are some customers who integrate POST as part of the application loaded by the bootROM such that there is control code that will decide whether to run the Self test and will then branch to the actual application. When the application starts, it will assume all the initialization of clocks, pinmux, external DDR memory is done and will assume device is in stable state since execution of self tests/diagnostics is complete.

    The other approach as you suggested is to use a secondary bootloader. This implements the device boot in two stages. ROM will load the secondary boot loader which is a user defined bootloader that performs all required initialization and then branches to application. In this case you can add the POST code to the secondary bootloader code such that it executes after initialization is complete and before control is passed to the application. 

    Hope the guidance helps. Let us know if you have any follow up questions.

    Regards,

    Rahul