D.I.Y. Illuminated tailcap

Hard to find words to describe that. :stuck_out_tongue:

I wonder how obnoxious the fancy “smart” tailcap is, with the defaults on the code I made for it. It, um, spins. But it only spins for a short while before it picks a color and goes into beacon mode.

Great work emarkd!

I haven’t checked out this thread in a while because I didn’t have anything to add.

First, let me say that I love the three matching colored S2+ tails!

Second, is a bit of news. I asked Simon if he could have the internal seals changed from the existing black rubber to clear.
He is instructing the factory to do just that. :slight_smile:

If I’m not mistaken this will allow you to have your seal and light it too!

I used pictures posted in the SS switch thread to explain what I was talking about to Simon. I told him that the black inner seal or seals had to be made of a clear or translucent material. I see the one main seal in the first picture below but is there a second? Can you guys have a look at what I sent and let me know if you think those two pictures cover it?



Edit: The sooner I get confirmation on this the sooner I can get this in motion…

J-Dub74, any change of being able to buy the new seals (or whole switch) separately once Simon gets these made?

I’d love to mod some of my existing S2+’s with the lighted tail caps but wouldn’t want to buy whole new hosts for them.

Thanks jdub, and that’s good news! There’s only one seal. That upper black bit is just an oring and it’s not exposed when it’s all put together. No reason to change it. I’ve been replacing my gasket with some bits of disposable painter’s glove. It works pretty well, but it can’t be nearly as resilient as a solid, thicker gasket would be.

I actually like it! That is special leds? Does it ever settle down or just go forever like that?

It’s still very early in the process but I already asked Simon to make some extras if he can work out the “clear” seals. I don’t know if it would be just extra seals made available or new switch assemblies but the seed has been planted on behalf of this lighted tailcap effort. There is also a new black stainless switch sample in the works that should incorporate the clear seal from the start. That’s just moving past the conceptual phase though so some time will be required to work out the details.

Goes on forever :frowning:

It is in my EDC now for checking out how annoying it actually is, and that is a confirmative 8-|
But the brightness is regulated by a 50K Ohm pot easily adjustable through the tail spring, so I could make it very dim and that pot also has a position which turns the tail leds off.

The leds came from tme.eu and have a inbuilt alternating slow and fast party-sequence. The six leds start synchronised, but within a minute it is this random psycho-stuff

Awesome, thank you! Look forward to picking up a few to mod existing lights.

FWIW, I updated STAR_1mode a little to remove the rest of its memory-related functions. It no longer writes to eeprom at all.

Would still need some small changes to run at a low mode instead of turbo, though.

The “alternating slow and fast party-sequence” looks pretty obnoxious.

Do you think it’d be okay with just a quick spin at boot, then showing only a steady color according to voltage? (the spin gives the voltage time to settle a bit, and visually indicates “measuring, please wait”)

I really should get or build some so I can test it and get the standby power down even further. I think I found a way to reduce standby by about 0.3mA by putting the MCU into a deeper sleep.

Don’t worry. Your led spin sounds cool and nothing like those crazy RGB party leds. Plus people could disable it if they wish.

+1, sounds really cool and not annoying at all, unlike my epileptic seventies disco tailcap.

I was thinking about a “spinning led” as well, might need 8-10 leds to really get the full effect though…

Something like this:

But I’d want it to be slower, and I think I would like it to have a “tail” (ie. one 100% lit led, one at 50, one at 15 or something like that - same color, just dimmer).

How many leds can one realistically fit on one of these boards if they are modified?

Wouldn’t want the effect on all the time though, that would quickly get annoying, unless it starts of fast, but then slows down to really slow after a short while…

Thank you very much! I’ll be giving this a go soon and may shoot you a PM to verify things before flashing. Still waiting on all the pieces to arrive :).

On a 19mm PCB w/ the donut hole in the middle? I’d ballpark 10 LEDs in the orientation used on rev6 and 20 LEDs in the orientation used on rev5. Note that we are limited on IO pins with the SO8 package: it’s got 8 pins where 3 are reserved for power/ground/reset. I believe TK also wants to use one for voltage monitoring. That leaves 4 pins available. Charlieplexing the LEDs should give 12 addressable LEDs. Offhand I don’t think that it would be possible to overload the voltage monitoring pin with 1 pin of the charlieplex, but if possible then 20 LEDs could be individually addressed. (It would also be a big pain to do since we also want to do voltage monitoring at the same time as the spin.) Depending on the desired patterns 50% of the LEDs can be hooked up in parallel to one another (typically those diagonally across from one another). For example, that would allow 4 pins to control 24 LEDs in pairs.

There would be no hardware PWM for these charlieplexed LEDs, so a tail effect would be harder to achieve. Software PWM could be used, maybe AVR136 (files) could be a good reference.

I don’t have experience with charlieplexing, but the ATtiny13A has very limited code space. Cramming spinning patterns in (many pin state changes for the charlieplexed pins) and also software PWM could be impractical. Depending on the pattern I believe that some (all) LEDs will also not receive 100% duty cycle…

Soft PWM is possible but pretty obnoxious to deal with. It’d be easier to use a MCU with more hardware PWM channels. But this is limited since it can’t spin or do PWM in deep sleep mode, and it probably should be asleep most of the time to keep standby power down. Hardware PWM is possible in a light sleep mode, but I suspect it might use less power in deep sleep even if the LEDs are brighter.

The current design uses 3 pairs of LEDs, though a 4th pair could probably be added without a lot of extra trouble. Three works well because they can be red/green/blue.

I’ve been too busy to get and assemble any tailcaps yet, but I have a Convoy S7 waiting for some extra bling (as if mirror-shined steel isn’t already blingy enough). :slight_smile:

Edit: It also occurs to me that the tailcap really doesn’t need to run at the full 4.8 (~4.0 actual) MHz. It’s probably a good idea to underclock the MCU to save power, especially if it’s not doing any PWM. I’m looking forward to seeing how low I can get the standby power…

If y’all want different versions I am happy to make a change, I am just waiting for some kind of a consensus or instruction. Obviously wight has the Eagle skills, he can do his own versions if he wants too.

I really like the current design… I just need to get some actual hardware; either pre-built or a bag of enough parts to build and adjust my own.

I really intended to build one of the “smart” boards this past weekend and then all sorts of unexpected things came up. I’ve got all the parts sitting here ready to go, just gotta put it all together. Hopefully I can get that done in the next few days. I’m anxious to see what’s possible with this design.