Hi, i have a simple application for MKL05Z32, and i bought 5 devices for prototyping. With small changes in the circuit it worked and i have a big pressure for the fabrication of the first 100 products.
The problem is that whitin those 5 devices i couldn't program 2, it's said to be secure, and couldn't unsecure it.
I'm using USBDM, and the information that it's secured comes from their software.
I can see a sawtooth in the reset pin.
I tryed many procedure exposed in forums, force reset low and make a power cycle, 100nF cap in the reset pin, etc..
I see some possibilities:
1 - Those devices comes randomly secured, and i'm doing something wrong trying to unsecure it. So, making 100 products, i'm risking loosing ~ 40% (2/5), that comes secured.
2 - Those devices were manually soldered, so i could have damaged those that i couldn't program. Would i get those message if it's a hardware problem?