Tool/software:
The Keywriter is an application designed primarily for programming the keys and converting the device from HSFS to HSSE.
During the keywriting procedure, one may encounter errors reflected by the non-zero value in the "Keywriter Debug Response" log on the UART port used by the keywriter application. One can decode this non-zero value using the following documentation to understand the cause of the failure:
In addition to returning the error code, the TIFS Keywriter also dumps the logs, which often provide more insights into the cause of the failure.
This FAQ discusses the various methods for obtaining these TIFS Keywriter logs.