I am extending the Micropython implementation on a Teensy 4 and similar. The set-up uses all flash beyond 1MByte for a file system. It happens more or less regularly, that the halfkay loader performs a full flash erase on firmware update, which wipes also the file system. Which is inconvenient. But that happens only when the file system used more than just a few blocks of the flash. I already tried to keep the upper 64kByte of the flash untouched, but that did not help.
So my question is: what triggers the halfkay loader to do a full flash erase, and not only erasing the sectors it need for the new firmware. At the moment, the firmware has a size of ~140k.
Note: With a MIMXRT1020-EVK board (with a different loader) this does not happen. It's a halfkay phenomenon. When it runs, I can tell by the duration of the short stop after a few actions what happens.
roberthh
So my question is: what triggers the halfkay loader to do a full flash erase, and not only erasing the sectors it need for the new firmware. At the moment, the firmware has a size of ~140k.
Note: With a MIMXRT1020-EVK board (with a different loader) this does not happen. It's a halfkay phenomenon. When it runs, I can tell by the duration of the short stop after a few actions what happens.
roberthh