Reply
Posts: 1
Registered: ‎03-16-2017

EM357 application bootloader memory protection

We are buying ETRX357-LRS modules preloaded with our custom application bootloader. Recently we pulled from the field several modules having the issue with upgrade. Comparing the bootloader images from troubled modules we our original bootloader found multiple differences (below):

 

Original app. bootloader (type = 2):

08000000: 00 04 00 20 4F 02 00 08 65 02 00 08 65 02 00 08

08000010: A7 0B 07 01 00 00 00 00 01 02 0E 00 00 20 00 08

 

Not working bootloader (type = 1):

08000000: 00 04 00 20 D5 1E 00 08 A5 0E 00 08 A5 0E 00 08

08000010: A7 0B 09 01 00 00 00 00 03 01 00 56 00 20 00 08

 

Another not working bootloader. Correct type, but has some other differences:

08000000: 00 04 00 20 8F 02 00 08 A5 02 00 08 A5 02 00 08

08000010: A7 0B 07 01 00 00 00 00 01 02 04 01 00 20 00 08

 

Question:

Is it possible that bootloader is modified by the stack or by the bootloader itself?