How to use mbed os 6.5 for LPC55S69

Unfortunately, the mbed team has discontinued support for the mbed os 6 series on the LPC55S69. However, according to my research, it was supported up to 6.5.

TARGET_NXP: Remove support for LPC55S69

For reasons unknown, it is now supported up to 5.15. Therefore, when we install 6.5, mbed cli get an unsupported error when compiling. However, the source code for 6.5 still contains the necessary hardware information for LPC55S69.

Mbed team most likely verified the operation test at least up to 6.5. Essentially, they should be available to use 6.5 selectively for us.

I’ve researched ways to enable it, using the 6.0 alpha version in git to break the unsupported MPU error out from the mbed cli. The following will be entirely at your own risk, as no official support is expected.

The 6.0 alpha has still information about LPC55S69 there. I’ll use it to overwrite os 6.0 alpha preprocessing file to os 6.5 directory. Of course, I won’t touch the source of the os files.


The compile on the mbed cli will now mostly work. The only modification is to add “define# MBED_CONF_TARGET_DEFAULT_ADC_VREF 1” to mbed_config.h etc. for AnalogIn.h.

Now the sample code works on EVK. However, I am not sure if it is really safe for complex code.