A D4 will melt thin plastic without much trouble , it will shrivel a crisp packet down to nothing from an inch or so away it doesn’t have to be black.
Let’s get one thing straight. It does not require a depleted cell for the problem to arise. It just so happens that one of the early observations was with a cell in that condition. Some users have reported triggering it with cells at 3.8V. In my case the cell was at 3.5V after the episode of severely heating the light while unattended and after a few further experiments to confirm the issue. A VTC6 or 30Q as recommended has a lot of energy left at those voltages!
Perhaps, TK could explain why the muggle bug is less likely to be activated with a fully charged cell. I would think if the state of charge had anything to do with this, a fully charged cell would allow more on time and deliver more amps than a depleted one.
I tested one of my lights in muggle mode with a 30Q cell charged to 4.0 volts. After 30 min I stopped the test, because the light hadn’t turned on, and I had lost patience waiting for it to do so.
From what people on this forum have reported, the bug only occurs on cells below approximately 3.8 amps in muggle mode.
Supposedly it does not occur with full cells. At least that’s what people who have tried to replicate it on this forum have said.
Why that is so? … I have no idea. But if that is indeed the case, then the chances of fire are much reduced. The light won’t produce max output at only 3.8v
Agreed.
The muggle mode bug is probably never going to cause a D4 to explode.
When the bug occurs, the battery isn’t shorting. It’s simply that the light isn’t ramping down due to heat when it should. For the battery to explode without a short, the heat transferred through the battery tube to the body would have to be enough to cause it to catch fire. That simply isn’t the case. The heat may cause damage to the head. It may make the light too hot to hold. It may even warp the battery’s shrink wrap… but it should be far below what is needed to cause the cell to spontaneously combust.
The thread has gotten a bit busy, so apologies in advance for a long multi-reply. I’ll probably post a couple of these while I’m catching up…
Yes, and all the tests passed. But the test plan didn’t include testing muggle mode’s “off” state for more than 5 minutes on a half-empty cell. That has been added to the plan though.
It’s probably not a great idea to give any device with removable li-ion batteries to a child. When the battery is taken out, it can cause severe burns in a fraction of a second. I know this, unfortunately, from first-hand experience… 
Due to the type of power source used, it is somewhat similar to handing a child a box of matches. It doesn’t really matter much if the box is taped shut; it’s not safe regardless of whether the tape is there.
That’s definitely a good side to all this. I’ve been trying for like a year to get manufacturers to use standardized firmware flashing pads, and trying to get someone to make the adapters commercially available. The driver side of things has seen good progress, but until now, the adapters were still limited to only what people can build at home.
Full details about the universal 4x2 adapter are here: [Oshpark] HQ ProgKey - Universal Driver Programming Key
It does not fit the D18, because the D18 doesn’t have any reflashing pads. It requires unsoldering the LED wires and pulling the driver halfway out, to allow a SOIC8 clip to be used.
However, it should work on D4v2 and any future Emisar lights… and it may also work on products from Fireflies, Mateminco, the BLF Lantern, and maybe others. This depends on whether Emisar’s adapter makes the wires remappable, and whether it is physically compatible with Lexel’s pinouts. But those details are not yet known.
I’m planning to make a photo-based guide, but it would be helpful to have more than just that. In particular, I don’t really know the best ways to do flashing in Windows and MacOS.
Not quite. As of a couple months ago, I get some compensation via Patreon. And I don’t do Emisar’s hardware enablement for free. So it’s not zero. But it’s a long way from a normal software development wage. Basically, I do about 90% to 95% of this stuff for free, and get paid for the other 5% to 10%.
In this case, no. The issue only happened on brand new hardware no one else had access to yet. Also, although the many-eyeballs factor of free software is often a huge benefit, it’s very uncommon for anyone to do anyone else’s hardware enablement QA work. When making software drivers for new hardware, nobody except the manufacturer is going to do any testing on that.
There is the additional complication that Emisar wants to keep everything private until products are released, because of cloning issues. The main consequence of publishing early would likely not be a reduction of bugs, but a reduction of purchases… since other companies might copy the design and get to market first. So publishing early wasn’t really an option.
Paypal is nice for buyers that way. However, please try to resolve things some other way first. Paypal can be pretty harsh to sellers, so filing disputes is kind of a “nuclear option” to use only after trying everything else.
To do that, simply ramp up to the highest level before going into momentary mode. It uses the last-ramped level. Or it can also use strobe modes, if you access one of those right before momentary mode.
Depending on how bright you want it, you may also need to raise the ramp ceiling first, which only needs to be done once. In the ramp config mode, simply click once when configuring the ceiling level, to raise it as high as it can go.
- Turn the light on.
- Click 4 times to get to ramp config mode.
- Wait a few seconds to skip the first menu option (floor level).
- At the second prompt, click one time.
- Wait until it falls out of the menu and goes back to regular mode.
After this, the ramp should go all the way up. Then simply ramp up to the top before entering momentary mode.
I try really hard not to be though…
I would pull out an avatar pic and make a joke, but in the context of this discussion it’s probably best not to. So I’ll just say this: People complaining don’t bother me. Even the occasional people making threats don’t bother me. What bothers me about all this is not catching the bug in the first place, not living up to my own standards… even if they’re impossible standards.
Thanks very much to ToyKeeper for the comprehensive and reasonable answer. And thanks to everyone else for keeping calm.
Just a quick note of thanks to TK and Hank for creating the most fully-featured and affordable flashlights many of us could ever dream of. Lessons will be learned, bugs fixed, and I hope the innovation continues.
[quote=ToyKeeper]
“Not quite. As of a couple months ago, I get some compensation via Patreon. And I don’t do Emisar’s hardware enablement for free. So it’s not zero. But it’s a long way from a normal software development wage. Basically, I do about 90% to 95% of this stuff for free, and get paid for the other 5% to 10%.”
No good deed goes unpunished.
The majority of us that have been a part of the community understand the depth of your contributions. I have been reading this forum since 2012, I just never registered an account. While I recognize the danger this bug poses, it has also been dramatically blown out of proportion. I see people who think this is an opportunity to get free product by filing PayPal claims, and they have an incentive to make this seem worse than it is. Some people acknowledge the bug and then state they are insanely worried, but for the majority of us who never use momentary or muggle mode it is hard to change to this mode by accident. “Those who can, do; those who can’t, complain.”
I Know that this bug is a PITA, and a bit of an inconvenience (not for me because I almost never buy the very first of anything 
), but at least there was no major damage to life, limb, or property. How many people had to die before Boeing acknowledged the software bug in the 737 max? How many people have car companies killed before issuing (usually forced) recalls? Look at the opioid epidemic here in the U.S., just to name a few. I can’t turn on my tv without a bunch of commercials from lawyers telling me I may be entitled to compensation.
My point is; hats off to Hank and TK both for admitting that there is a problem and trying to help find a solution to that problem. We could use more of that in today’s world I think. Would it have been nice if there wasn’t a very weird and obscure bug in the software? Yes. Is there a solution? Yes. Will it be easier for experienced modders? Probably. Will I or anyone else that attempts the fix themselves become more experienced? Most Likely! We can whine and moan about this, or freak out about what could happen. I could also step outside and get hit by a car or a rogue meteorite, but I’m not gonna spend the rest of my life hiding in my house.
Thanks TK for quickly fixing this bug, and thanks Hank and everyone else for working to get that solution out “to the masses”.
Sorry for the long rant, but this post has been a long read.
I’m typing this on a windows PC and patch Tuesday is just a couple of weeks away 
I’ve been flashing from my laptop under Windows 10 and would be happy to help with that part. Getting the right driver installed was the toughest Windows-specific problem I encountered, but there turned out to be a very simple solution to that.
There are others who are better qualified, but please let me know if there’s anything I can do.
Yep, there are currently operating flashlight brands that would not even consider making a bug like this public.
Unfortunately when you make something more complicated there are more failure points, x100 for coding.
Here's how completely naive I am about this whole flashing f/w thing. I figured it was just being done in Windows, which is how I plan to do it, hopefully, maybe.
My windows machine that I used for flashing crashed and burned right at the moment of a recent update.
I’ve reinstalled 7 but not upgraded to 10. Yet. IIRC it was a pain to get all the software installed but I put in all the IDE stuff to hopefully pick around at the code.
For files that are to be installed as-is do you need anything beyond the USB driver? There are so many different tutorials on the site with slightly different approaches.
Love the idea of a walk-through of what needs to be installed then how to flash the .hex file TK posts.
Couldn’t help but be reminded of this dramatic childhood memory:
Ordered the key-pcb a couple of days ago from OSH PARK. Got this email from them today. Apparently, these are build-to-order.
=================quote=====================
HQ ProgKey v1 -ABC- copy sent to fab.
Hi Terry!
Your boards are being made as you read this!
We've sent the panel containing your boards to the fabricator. We expect to get them back around July 29th.
In case you're interested, there are 88 other orders on the panel along with yours, adding up to a total of 555 boards. Neat eh?
Awesome review/overview/manual, as always, TK. If I want a reference manual for a light, I just save a copy of your review. If there isn’t one, then I’m out of luck and will have to throw the light into the trash as it’s impossible to ascertain the proper mechanisms and rituals of operation 
.
Ah, such loveliness. Sleep, little MCU, sleep… anyone who keeps them running without good cause is off my list of survivors when the aliens come and I load up my rocket for escape. Elon’s admittedly ahead of me on the actual construction, but mine is still better as it has more LED’s.
On the software side you just need the USB driver for your controller and the main AVRDUDE program to flash a hex file. It looked like getting the right driver installed would be ugly, but I ran across a utility called ZADIG that does it for you and eliminates all of the hassle. You just plug in your controller and run ZADIG. It will detect and identifier your controller. Then you tell it to install “libusb-win32”. You can then run AVRDUDE to flash the code to your light’s controller chip.
Got the same mail today with exactly the same text.I ordered v2(123)on 07/21
My case still in a dead end. Hank’s programming tool won’t help and I don’t know what the owner will said.