Weekly Update: June 10, 2017

One step forward, one step back, and maybe a step or two to the side.

No, we’re not dancing. I’m describing the power for the V3. With BronyCon approaching faster than I’d like – 9 weeks away from now – I can’t really take too much time to re-design things. I tried two things: One, a separate power supply board, and Two, using a single buck/boost regulator.

Neither of those are going to happen.

The separate power supply board is simply too expensive to start off with. If I was getting 500 of them, that wouldn’t be an issue, but with a production run of around 100 units, it’s about 3x more expensive than it should be. That said, an updated V3, when I have the opportunities to purchase in larger quantities, may feature a separate power supply board. Additionally, such a power supply board would be available separately for whatever sort of crazy contraptions you can think up. I AM going to be integrating most of the power supply board’s design into the V3 – That is, the ATTiny84 for control and additional GPIO and battery monitoring.

The voltage regulators, on the other hand, are going back to the ones that have been tested and I know work. The single buck/boost one I simply could not get functioning. If that was an issue with the soldering, or board design, or something else, I don’t know – And I don’t really have the time to figure that out. Both of the other regulators I have tested and work fine. Thankfully, there isn’t much of a price difference, it’s just a matter of squeezing them onto the board. Which I’ve already done.

In other news, it seems unlikely that there will be a case ready for BronyCon. While I really hope this next design will be the one I get a fully functioning prototype out of, I’ve said that for the other ones, too. I’ll be honest – There is entirely a possibility that the V3 will not be ready before BronyCon. I really doubt that will happen – Especially with having someone else manufacture them – but it IS possible that things just don’t work out. That said, there’s still about six weeks to work with, so I’m not terribly worried yet. I’ve already placed an order for more prototypes, so right now I’m just waiting for them.

At this point, I’m sure you know the drill. DiscordTwitterFacebook.

A most shocking update

Greetings, ladies and gentlemen! I’ve got a great big nice update for you today.

Over the last week or so, the parts orders that I’ve placed have trickled in and I’ve accumulated quite the pile of boxes. Today, I finally got the “Big One” – The final circuit boards! So, I immediately set about assembling the first “Production” DigiBadge V2 (I’d have assembled a pendant, but there’s one package due in later this week I still need). Used the solder stencil, put it in the reflow oven, hand-soldered the screen and battery on. Drop some batteries in, flip the switch…

Nothing. Batteries get warm. Out comes the multimeter! Check the resistance between ground and supply. There’s a short. Spot two of them on either side of the microcontroller. A dab with the solder wick fixes these real quick. Put the batteries back in, hit the switch.

Nothing. Except wait, the microcontroller’s getting hot! That’s typically indicative of backwards voltage. Check things, double check things, everything looks right. On a hunch, I look at the battery pack, and go grab my previous V2 prototype. Surprise! The battery packs are not identical – The ones I had been using had switched pins compared to the ones from the bulk source.

So I sigh in exasperation, take the batteries out, put them in backwards, and switch the thing back on. I didn’t expect much, as reverse polarity is typically the easiest way to fry a chip, but the badge fired right up and sprung to life, working absolutely splendidly. This issue will be addressed in the upcoming V2.1 DigiBadge, but if you get a DigiBadge at BronyCon or until I run out of stock on the V2, you’ll have to remember to put your batteries in backwards. Additionally, as this is a part issue with the battery holder – Something shared between the DigiBadge and the Pendant – this will mean that pendant batteries must also be placed backwards. As with the DigiBadge V2.1, this will be addressed in a Pendant V1.1.

But there is good news! The issue with the SD card resetting the chip seems to not be present with this specific badge. I’m not going to promise it’ll work with your V2, as I’m not 100% sure WHY it’s working properly, but it’s allowing me to debug and address the issues with the code. I’ll be keeping my eye on all of the standard-production V2s and seeing if it may have been an issue arising from me hand-soldering parts that weren’t designed to be hand-soldered. If it does rear up again, I’ve got an idea for how to address it in the V2.1.

If you haven’t yet, you can pre-order the V2 and the Pendant over in our shop!