Pretty much all PWM-based lights will whine, especially on medium modes. However, the fast PWM setting is a high enough pitch that most humans can’t hear it. If you can hear a faint 19 kHz tone, you must have truly exceptional hearing.
One other possibility is perhaps you’ve flashed it with the wrong fuse settings? That will change the MCU speed and thus the PWM speed. It should be “-Ulfuse:w:0x75:m -Uhfuse:w:0xFF:m” for a low fuse of 0x75 and high fuse of 0xFF.
Hmm I’ll have to check the fuses. I compared it to a whistle app, and the driver whine sounds like about 15khz
Just wondering if the majority would prefer the battery check before strobe in the hidden reverse loop?
I use a ZL600MK2L2 as my daily carry and I would enjoy not having to go through the stobe to check the battery every day when I get home.
Can you specify what I would have to do and what I would see to check the battery from off?
Example: 4 quick clicks from off = full bright then medium bright while you click, then one second pause off and flash battery level at high.
As a child my doctor thought I was partly deaf. Looked at my mom like “Poor woman, doesn’t realize her child can’t hear”.
Test results, exceptional hearing. Beyond the average range. The doctor had been pretty sure but I wasn’t deaf, I was just ignoring him. 
Likely wasn’t saying anything that interested me. My mom knew it but it was more amusing to let the results inform him.
As long as its faint, 19 kHz isn’t too annoying. For me at least, high frequencies lose much of their volume if an ear isn’t actually facing toward the source.
Okay. There were no objections, so here is the source (so far) for the BLF EE A6 firmware:
This is not final; it’s just what we’re working with so far. At the very least, all the hardcoded values will be recalibrated to fit the production samples when they arrive, and there may be other changes as well.
At that link, the .txt file describes the interface in detail. There is also a .png with a UI diagram, but it’s a bit out of date.
As for getting to the battery check mode, the sequence is: Fully click to turn the light on, medium tap (turbo), med tap (strobe), med tap (battcheck). The reason they are in this order is because it gives the fastest access to turbo, which gets used a lot. After that, the fastest access is strobe, which tends to be needed quickly when it’s used. Battery check / beacon is usually less urgent.
is anyone of you firmware-gods interested in selling ready to use drivers ?
I doubt it, that is quite a different undertaking, once someone starts doing that he/she can count on quite a mass-production. Led4power can not keep up with the demand for his LD1 driver either. Ledsmoke has a too busy life to continue his BLFDDdriver service.
Perhaps Richard will pick up this driver with this firmware once it is finished?
Personally I would happily settle for pre-flashed Attiny's, that should be a lot less work. But if needed, Richard does that service too.
Then I'm not part of those two crowds, my UI for this driver (in any light) would be moon->350mA->fullFETblast, no memory ☺.
But the 4mode setting of your A6 firmware is good second favorite of mine ☺
It sounds likely that there may be a group buy for a firmware tool kit, and the code is available, so if anyone wants to change the modes or UI it should be reasonably straightforward to do.
I’m not interested in selling drivers. Aside from never having actually built one, I think selling stuff would take the fun out of this hobby. But I’m happy to keep making code for people to use.
In any case, the mode groups in the current version are:
0.3lm ............................. 1600lm
G1: moon, low, med1, med2, high1, high2, turbo
G2: low, med, high, turbo
Both groups are spaced on a visually-linear scale, but they don’t have the same lowest mode.
it will be the driver for BLF Eagle Eye A6 ??? G2- Super!
No production samples have been made or tested yet, so we don’t have any confirmation on final specs. All info so far is about prototypes and what we hope to build.
A Group but would be great. I would like a firmware tool kit. Having two lights with different modes for different purposes. Count me in
I would love to GB a correct firmware tool kit. Count me in [/quote]
+1!
If there is a firmware kit group buy, it’ll be in a different thread. 
Modes sound great, I hope the few people in the “4 modes, any more or it sucks” group appreciate the work for it.
Oh yeah, and the dress is gold and white.
Yes gold & white…….
4 modes are way too much (and I do appreciate the work :-) )
*blue+black*
Nope, that’s it. The group buy is over. You had to go and mention “the dress”, the symbol of everything wrong with the modern world. Now we’re doomed to an eternity of stock 2.8A nanjg drivers with on-time memory and blinkies in the main sequence.
As usual I don't know what is going on in the last few posts. I would suggest that if you all readdress the problem that the problem will be addressed.
Hrrmph. They started it.