AnsweredAssumed Answered

How to reduce Kinetis flash bootloader v2.0.0 code size

Question asked by Isao Takashima on Jun 22, 2017
Latest reply on Jul 4, 2017 by Hui_Ma

We want to implement firmware update mechanism to our system which use the KL17Z.

We understand that the KL17Z integrated ROM bootloader, but we want to use our custom protocol on the UART, then we cannot use it ROM bootloader.

NXP release below bootloader reference project.

- Developer’s Serial Bootloader (REV 13)
- NXP_Kinetis_Bootloader_2.0.0 package



We checked code size, the Developer’s Serial Bootloader code side is about 1KB, but NXP_Kinetis_Bootloader_2.0.0 package code size of KL25Z is about 16KB even if enable only UART.


So, we cannot find out URL link address of the now. But we had download few years ago, then we can build it project and check code size.

Therefore we think that it is better to use NXP_Kinetis_Bootloader_2.0.0 package.

But it code size is very large.


Here is our questions.

1. Does NXP recommend that use NXP_Kinetis_Bootloader_2.0.0 package instead of Developer’s Serial Bootloader(AN2295SW)?

2. Please advise how to reduce NXP_Kinetis_Bootloader_2.0.0 package code size.

3. If we can use Developer’s Serial Bootloader(AN2295SW), please let us know URL link address of


Please reply as soon as possible.


Best regards,