LPC540xx Image_marker value 0 or 0xEDDC94BD?

[danielgull]

Hi

I am a bit confused by the User Manual UM11060 Rev 1.5 25 November 2019.

On page 24 in Table 9 "Plain image layout" the "image_header" is declared as a "Reserved" block with a value of "0x0".

On page 25 in Table 11 "XIP image layout" the "image_header" is declared as a "Reserved" block with a value of "0x0".

On page 26 in Table 12 "Image header for the LPC540xx devices" the "image_header" at the table header offset "0x24" describes that this parameter should be "Always set to 0xEDDC94BD."

The MCXUXpresso SDK for "SDK_2.7.0_LPCXpresso54018" uses the value 0xEDDC94BD in the startup file "startup_LPC54018.s"

So what is it now? Is the "image_header" "0x0" or "0xEDDC94BD"?

Many thanks

Dani

[diego_charles · Accepted solution]

Hi Daniel ,

I hope you are doing well.

The image marker should be always  0xEDDC94BD, 

The HEADER OFFSET ,  should by pointing to the image header marker,  the first element of the image header structure ,  represented by the Table 12.

The offset 0x24, also named image_marker (in the image header structure) is also set to 0xEDDC94BD.

The application note  LPC540xx Image Header Structure  provides more details on this.

I hope this helps.

Best regards, Diego.