KL25Z can only enter bootloader mode and blinks 8 times with pause (= error)

[svdm]

I'm using a FRDM-KL25Z board. When pluggin the device to my laptop (win 11) nothing happens. When entering bootloader mode, the device is shown on my laptop as BOOTLOADER, but the status LED blinks 8 times with a 2 second pause. Tried updating the firmware following these instructions (https://mcuoneclipse.com/2014/11/01/illustrated-step-by-step-instructions-updating-the-freescale-fre...) but without succes. I also noticed the application version is: 0.00 ...

Does anyone has an idea how to solve this? Thanks in advance!

[CarlosGarabito]

You need a computer with Windows 7 and then follow Erich Styger's steps to update your bootloader.

[svdm]

Thanks for your reply Carlos! Are you sure it is not possible to use the board with an win11 machine? A couple of weeks ago it did work with my win11 machine. Or could this be due to a recent update?

[ErichStyger]

The issue is with Windows scanning USB storage devices, which confuses the older bootloader version of OpenSDA.

I know for sure that updating the boards with Win7 works (that's why I keep an old Win7 laptop on the shelf, e.g. using https://mcuoneclipse.com/2014/11/01/illustrated-step-by-step-instructions-updating-the-freescale-fre... ). You might try a Win10 based approach I have described here:

https://mcuoneclipse.com/2018/04/10/recovering-opensda-boards-with-windows-10/

(but I have not used that one for years as doing things with the Win7 Laptop instead).

I hope this helps,

Erich