KL25Z to KL26Z migration

[marcelosousa]

I have a working custom board with KL25Z128VLH4. I am planning to move to KL26Z or KL27Z due to the lower price and additional features. I tried to populate the same board with a KL26Z128VLH4, but it doesn't work. It always show the message “Device is secured. Erase to unsecure?” and it never succeeds. I tried both OpenSDA and Ulink2 interfaces, but the results are the same. According to the reference manuals, there is no hardware difference to justify this behavior. Do you have any clues?

[BlackNight]

Hi Marcelo,

in your debugger connection settings, have you specified the KL26Z device?

Erich

[marcelosousa]

Yes, I did. When the "device secure" message is shown and I confirm to unsecure, the following error message appears: "cannot access memory (@ 0xf0002ff0,  Read, Acc Size: 4 Byte) ". This address is the Device Id register. So, I can presume it is communicating via SWD properly, but commands are not executed. 

[BlackNight]

It looks to me that the connection itself is not reliable. The debugger tries to read the device ID register, but fails. I would check the solder points/etc.

Erich