TMS320F28335: Boot from Flash not working

Mohan,

Can you confirm the boot pins are driven to all "1" to boot to flash as shown below?  Was there any other change to the project except the CCS version, especially the .cmd file?

Best,
Matthew

Hi Mathew,

yes, boot pins are set to High.

It's a custom board, I tested in two boards of the same configuration. The behavior is the same.

There were changes done in the application post main in recent changes. I loaded the last baselined build where the changes were not considered. Even then its not working.

Please do let me know what other steps I can take to solve this, or any method where I can check the boot-to-jump addresses can be verified.

Regards,

Mohan

Mohan,

We need to try and emulate what is happening in standalone boot mode when you are connected via JTAG.  After you load the .out file, ccs will automatically go to main for you.  We want to not use this, so if you execute a CPU reset it will then jump to the start address in the Boot ROM.  If you run after this, I expect you will see the same bad behavior in stand alone, but please verify this, i.e. the Boot ROM doesn't get to your code in flash but is hung somewhere.

We can then load the ROM symbols and debug from there. C:\ti\c2000\C2000Ware_4_03_00_00\libraries\boot_rom\f2833x\v2_0\rom_sources

Just to circle back a bit to your original message, you mentioned that this was previously working with an older version of CCS.  Has there been any other changes to your system such as HW/PCB, etc?  It will be helpful to know what other differences might be.

Can you confirm the marking on the top of the MCU is F28335 and not F28235?

Best,
Matthew

Hi Matthew,

To confirm, I am using F28335, in my team we use only two controllers one is F28335 and the other is F28388D.

The board I am using is a custom board based on F28335 and no changes are made to the hardware.

In debug mode, I verified the boot mode pin values and all are high.

I debugged the unit as per your comments and below are the observation:

1. All the jump addresses were as expected.

2. Control transferred from Boot to cinit and then to main without stalling anywhere.

during the debugging the boot mode pin status gave a value of "F" which was matching for the boot from flash settings.

but when the same was power cycled, again the issue was the same it didn't boot.

Please let me know what else I can try.

Thank you,

Mohan

Mohan,

I want to see if there is some issue with the power up sequence.  In stand alone mode, after power up (and the part does not boot), can you manually pull XRSn low then back high and see if the device boots correctly?  If this works, then we need to look at the VDDIO/VDD/VDDA rails and XRSn as they come active to make sure we are within the DS spec for these during power up.

Best,

Matthew