Update for my F6 driver:
Boards arrived, I populated one (should have made a photo; will do when I flash a new firmware next time) and wrote a firmware for it, based on mokkadrv, but highly configurable, and making use of 2 status LEDs:
By default it has 3 modes, L,M,H (number of modes and brightness levels can be reconfigured).
When off: A short click switches to the last mode (high), a long press starts in the first mode (low), keep holding the button to get to the higher modes. A double-click starts strobe. So no memory - but that can be changed, see below.
When on, a short click switches off, a press&hold cycles through the modes in a L-M-H-M-L-M... fashion.
A very long press/hold activates the battery indicator; the red status LED blinks the number of full volts, the blue one the tenths of a volt, e.g. 3*red, 8*blue means 3.8V.
A 4*click (4 quick taps) let you change the current modes' brightness by then ramping up&down via press&hold, a short click sets that new level - temporarily, i.e. it does not survive a power loss. So you can adapt the levels to your current situation without changing your standard config; but it can be made permanent, see below.
A 6*click leads to lockout mode, the light can be reactivated by a 3*click.
An 8*click brings you to the configuration menu, where you can
- add or delete a mode
- configure whether a short click when off starts the light in the first mode (low), last mode (high; default) or memory.
- configure whether a long click when off starts in the first mode (low; default), last mode (high), memory or ramping.
- permanently save your current configuration, reload it, or restore the factory defaults.
18kHz PWM, step-down on low battery (3.0V), shutdown at 2.8V.
I have plans for a couple more features, and some of them before I'll release these (e.g. currently double-click and triple-click lead to strobe and can't be changed).
I also ordered some components (resistors, status LEDs etc) so I can send kits (board and components) later.