how to enter ISP mode via user application--LPC Board

[anshulkhare]

Hi all,
i am trying to find API for entering in UART ISP mode in LPC board.
There is a firmware which is up and running on the board, from that firmware, i need to call the API to enter into ISP mode.
can anyone guide me on this, if it is possible from user application?
is there any application note or example is available for the same?

can anyone guide for the application note for communicating in ISP mode using blhost?

Thanks in Advance.

[anshulkhare]

@Pavel_Hernandez Thanks for your reply.

in ISP mode can we upgrade signed image on the chip where security is enabled, using blhost?

[Pavel_Hernandez]

Hello,

If you mean "security is enabled" is the "secure boot" turned on, so you can't program a new image anymore.

Best regards,
Pavel

[Pavel_Hernandez]

All ISP, JTAG. IAP can be used to program after enabling a secure boot. but you must use it program signed image, otherwise, it can't pass the secure boot check.

It's not possible to program the flash with IDE debug because it's not a signed image when debugging code.

AN12283 LPC55Sxx Secure Boot
AN13037 LPC55Sxx Debug Authentication

Maybe that app note could help you.

Best regards,
Pavel

[anshulkhare]

Hello @Pavel_Hernandez 

does it mean if secure boot is enabled ,in that case user application can not be upgrade using ISP or IAP?

[Pavel_Hernandez]

Hello,

I review your information and I recommend review the RunBootloader API chapter 9.3.4 in User Manual.

The ROM bootloader provides an API for the user application to enter the ISP mode
based on the designated ISP interface mode.

And suggest review the documentation for the blhost. MCUBLHOSTUG.pdf (nxp.com)

This thread maybe could help you. Solved: Configure LPC55 to enter/re-invoke ROM Bootloader ... - NXP Community

If you have more questions, please let me know.

Best regards,
Pavel