The GAT Stand - Badge Addon Holder

Supercon is over. A number of people got these stands. I tried to make sure addon makers got them. The stand was demonstrated to many people who generally liked the idea of scheduled or light-sensitive operation. A few of you traded or bartered for them to have them for yourselves - I appreciate it.

So what’s next?

• I still have a lot of parts. I will be selling fully assembled and kit versions of this in the coming weeks.
• Also in the coming weeks I’ll collect and open up all design resources I can, such as schematic, board files, acrylic cut files, and holder base STEP file.
• I’ll implement at least a basic USB CDC device for configuration of the RTC and scheduled, and maybe I2C slave read/write commands.
• The user manual will be expanded with photos and should be easier to understand.
• A photo-based kit assembly guide will be created.
• Have other plans and ideas…

If you’d like to support the project, you will be able to buy these in a couple weeks.

haven't had time to focus on this project at all - been super occupied with the nametag for the prior week.

I think I got roughly 100 boards done for supercon.

cutting final acrylic pieces now. about 2/3 will be in dark smoke and 1/3 clear.

all the bases for 100 or so units were 3D printed as I was doing nametag assembly. mostly black but also have white, red, and retro beige.

final soldering and assembly of these will be done during con. if someone wants a "kit" then maybe I can make instructions. it's a bit fiddly to get the soldering done right but people with attention to detail could do it.

Progress has been slow. Trying to modify about 100 boards for Supercon in case there’s demand. There’s no time to fully assemble many, so I’ll make up an assembly instruction guide at Supercon. Some final acrylic testing remains, then I can start making stands. Total engrave and cut time is about 6-8 hours.

I thought I got my USB connections backwards but thankfully I didn’t. I should have a working UF2 bootloader to make firmware updates easy. This will likely be what I am working on and testing on the first day of Supercon unless some time frees up. Worst case, there is a ROM vendor bootloader.

I’ve shown the design to a few people. They like it and want one, which is promising.

Started reworking boards to fix the power issue. I haven't even tested / seen how well this will work in acrylic yet. Perhaps getting ahead of myself... about 30 units have been repaired so far. Will try to get to 100. My other project is due in tomorrow so I only have the rest of today to do this.

Code should be finalized for con. Basic soft power with memory works. I have added the automatic brightness detect option as a jumper setting. Maybe I'll add a UF2 bootloader to allow easier updates by end users. Kinda braindead but the code for this already exists, so it shouldn't be hard to get working...

The filament-as-lightpipe idea works very well. Now to find a glue gun to attach it. Or maybe I'll just melt the filament into place... but I risk melting and damaging the LED. Will play around with this.

I hope to have photos for this project by the end of the day - because after today, I won't have time to work on this project until free time at Supercon.

Having some issues with the first boards.

The output control IC lists in the datasheet that a large value capacitor is highly recommended, but it is causing brownouts on the badge. This could have been mitigated with a small change in design (specifically, moving the fuse after the 3V3 vreg but before the output switch as there's nothing else on the 3V3 that is likely to cause a fault / need protected) but it's too late for that now. I tested a few different configurations:

• Paralleling a 10uF cap on the input, things were improved. I could hotplug microdoom, but could not start it cold.
• Removing the large bulk cap on the output, I could reliably start microdoom.
• Testing another board without the parallel input cap and with output cap removed, things were still bad.

For these to work at Supercon, I'm going to need to hotplate and remove every bulk output cap and solder in a 10uF input 0603 cap. Very time consuming.

Designed the base stand and acrylic insert. Very rushed but it should work. Then I went to sleep.

PCBs arrived today. Just opened the box. I'll cut out a base and test fitment while testing the code. If it works then I guess I'll be laser cutting and 3D printing all day...

One con of this design is that it is _very_ small and light. This is also the design intent, but does mean that heavy / thick USB-C cables can easily move and tilt these around. Use flexible cables.

I've been busy preparing other projects for Supercon 8. Those should be wrapped up tonight. Tomorrow I will focus on the GAT Stand.

PCBs are expected to arrive tomorrow. Worst case, they're here by Wednesday. I'll only have a day or two to experiment with base designs and cut acrylic for this project so the next couple of days will be packed.

If I can get this done, this will be available as a partial assembly kit at Supercon. Limited bases will be available due to 3D printer time.

I added ambient brightness detect code yesterday. Still not doing anything with it; the code was copied from Peppercon 9. Will need to test ambient light levels to get good ideas for hardcoded defaults. Need to hook into buttons to enable / disable the feature and show status somehow using the RGBLED. Will likely need to redo the LED code to allow for, say, breathing patterns; the code sucks right now.

For SC8, I am considering adding I2C scanner and arbitrary read/write routines. I may not have time for this until Supercon. I think it would be a handy tool to have if addons are a focus... guess what I do here will depend on features and capabilities of the Supercon 8 badge.

edit 2200: have tracking number for PCBs. looks like Monday I get to design the acrylic stand and 3D printed base.

Code status:

I started and basically completed initial code last night. It should be enough to have soft power buttons with memory.

RTC is initialized but has no way to set it. A flashing LED akin to a flashing 12:00 on a VCR will exist until I implement a way to set the clock. Even if there was some way to set the RTC, there's no alarms / timers implemented yet.

Backup battery is used to store non-volatile settings related to soft power.

I2C master support isn't implemented yet, but should be a mostly copy-and-paste job. However, there isn't anything to implement yet - every addon is different and I don't have anything in mind. Maybe I'll put something together at Supercon.

Addon GPIO ports are configured as per the provisional GAT standard to set the ID of the addon to 0. This is a weak pulldown on both pins so nothing else is happening. I may implement arbitrary GPIO or a WS LED driver that can be used on this port. Long-term goal would be Corsair iCUE support to control external RGBLED via the PC.

Board fabrication status:

The PCB stackup was rush completed and sent for fab on 20241014. The front sub-boards are half done. The main board is fabricated but SMT assembly has not yet started. I hope there are no delays...