Thursday, August 16, 2018

Gherkin Gore

A failure to Gherkin

Found Gherkins on Amazon. This is what arrived.

It was loose in a large box with several other items (That now smell like pickles). The only padding was the bunched up brown paper.

Gherkin gore. 4 of the 12 bottles were cracked open. There must be a trail of pickle juice somewhere.

Monday, August 13, 2018

Luddite 2

ANSI 60% on a Pro Micro

Second version of the Luddite. Fits fine in a cheap plastic case. Or can be assembled with a second PCB as a base like the first version.

The circuit is the same as the first version, some components were moved to avoid the stabilizers.

Gerber file on github. Firmware.

Luddite in a cheap $10 plastic case.

Top of the assembled PCB. Diodes and resistors.

Bottom of the assembled board. Mini USB connector, 24pin socket, and MOSFET for LEDs. The tiny ESD protection chip is just below the mini USB connector.

Closeup of the USB connector. The 4 pads are for the pigtail to connect to the Pro Micro, in the same way as the GNAP!

Wednesday, August 8, 2018

Another black Pro Micro that's not the right size.

Odd sized Pro Micro that's too wide

There are black Pro Micro's on eBay and AliExpress that are a different size than the normal Pro Micro. This makes it incompatible with any PCB designed for a normal Pro Micro. It's has the same pinout and the same circuitry, but will not fit.

The top of the fat Pro Micro. It is 0.1" wider than a normal Pro Micro. The only good thing is the type of Micro USB connector it uses has feet that fit into the PCB. It should be much harder to break the USB connector off.

Bottom of the fat Pro Micro is flat. You can see the holes that the USB connector fits into.

On the left is a normal size black Pro Micro, compatible with the common cheap blue ones. On the right is the fat Pro Micro. They both use the larger version of the AtMega32U4.

Side by side comparison. Normal black Pro Micro, fat Pro Micro, Pro Micro with Mini USB connector.

End to end comparison.6

Monday, July 23, 2018

Green Eggs

Someone doesn't like green switches

Something to appease your coworkers who hate clicky switches.

This was originally supposed to look like a doughnut. But it makes a better egg, a green egg.

8 switches connected to a Pro Micro.

Runs a simple Arduino sketch. Gerber files on github.

Friday, July 20, 2018

Monster POS

5x5x9 Macropad with POS keycaps

225 key macropad covered with POS keycaps. Most are DSA some are DCS. 2x1, 2x2 and 3x1 keycaps.

 Mostly DSA profile. The "Yes" keycap is DCS.

All POS keycaps.

Showing the base of the keyboard and the PCB and plate layers. The Maple Mini sticks out the top.

Monday, July 16, 2018

Half n Half

Another split keyboard

I made this a while ago. It's sort of a wider Gherkin with dedicated thumb switches.

Construction is the same as a 25 or foobar. It is a single PCB design that can be assembled flipped, either left hand or right hand side up.

Gerber files on github. Firmware on github.

Blank XDA keycaps. XDA has many smaller space bars. Since the space bar is isolated you can use whatever size you want.

Both halves connected with a TRRS cable.

A second PCB is used as a base. 3M rubber bumpons.

M2 spacers and screws. Pro Micros and TRRS jacks.

Wednesday, July 11, 2018


Too many pens

EasyEDA/JLCPCB have been sending a pen with each order. The collapsible "Pill" pen is from Flashquark.

JLCPCB stopped including a pen in the last few orders I've received. They must have run out.

Monday, July 9, 2018

Tall and Short

Two 4x4 macropads

A 4x4 with a SA keycaps and a Chocopad from

Fat and thin. The two extremes available in current mechanical switches and keycaps.

Both are powered by a Pro Micro.This is a Rev 1.0 Chocopad. The ones is selling now are black and have a nice bottom PCB.

1.5 inches tall vs 0.875.

Monday, July 2, 2018

Kolea Case

Top and bottom plates for the Kolea

I broke one of the switches on my Kolea when I dropped it. The switches are very exposed. I made these plates to make the Kolea much sturdier. It will also make it possible to use plate mount switches as well as PCB mount ones.

Gerber files on github.

The switches are held much more securely with the top plate.

I scuffed up the PCB to take off the shine. There is a hole in the bottom plate to access the reset button the Teensy LC.

The plates are held together with M2 spacers and screws.

Monday, June 25, 2018

Alps Prototype

Experimenting with an Alps GNAP!

Made a top plate and PCB for Alps style switches. The plate matches the plate for the regular GNAP!

Alps uses a 1-1.2mm thick mounting plate. I made the PCB out of 1.2mm FR4 material. The switches fit well and are secure. Unfortunately the 1.2mm flexes a lot more than the usual 1.6mm FR4 material.

On the Rainbow Cat Vomit I also used 1.2mm FR4, but had many more supports in the middle. I may try using 1.6mm and see how that works. The switches just won't lock into place, but the PCB should hold them down.

The other problem is the 2u stabilizer. There are many different styles. I will probably use the MX compatible one since the Signature Plastics Alps 2u keycaps use those.

Wednesday, June 20, 2018

STM32 Flashing

Programming a Maple Mini

These are the steps to flash a Maple Mini with TMK for the 5x5x9 board.

First you will need the original Maple Mini bootloader. This file is in BIN binary format.

You will also need the compiled HEX file from TMK. A walkthough for compiling TMK with ChibiOS is here.

The STM32 Flasher Demo can be downloaded here. You will need to register to download.

A 3.3v USB to TTL Serial adapter. Often called a FTDI cable. It must have 3.3V i/o. Most have an option for either 5v or 3.3v. Install drivers for the USB serial adapter if necessary. It should show up in Windows Device Manager as a COM port.

This USB Serial adapter has a jumper to switch between 5v and 3.3v output.
You will need jumper wires to connect TX, RX, GND, and 3.3v.

The connections on the Maple Mini. On the 5x5x9 these are broken out to a header.

The BOOT1 pin needs to be connected to ground to run the Serial bootloader. On the 5x5x9 there is a switch that makes this connection.

To enter the serial bootloader you hold down both BUT1 and RESET. Then while continuing to hold BUT1 you release RESET. Then release BUT1. It will now be in Serial bootloader mode.

You can now run the STM32 Flasher (Demonstrator GUI).

 Pick the COM port of your USB Serial adapter.

If you pick the wrong COM port or the Maple Mini is not in Serial bootloader, or the TX/RX pins are reversed you will get this error. Try again. The program is buggy and you may have to quit the program if you get this error.

If it connects you will get this screen.

Do not change anything on the next screen.

Click on "Download to device". Click on the file selector.

Change the file type to BIN and select the Maple Mini Bootloader file.

 Click next to flash to bootloader.

It should take only a few seconds.

When complete click back.

Click the file selector again.

 This time select HEX files and open the compiled TMK hex file.

 Click next to flash the firmware file.

 Wait for it to finish.

Close when done.

You can skip flashing the bootloader the next time.

Monday, June 18, 2018

Gnapkin Plates

Forks and Spoons

Made some PCB plates for the Gnapkin.

Files on github.

Assembled with Kailh Burnt Orange switches. The top of the plate has as copper layer.

 Bottom plate is plain and also has a copper layer under the soldermask.

M2 spacers and screws hold the two plates together.

Access to the USB port on the Pro Micro.

I added blue LEDs under the switches.

These are actually 3mm round flanged LEDs. They fit snugly in the bottom of the switches. This would interfere with a click bar if the switch had one.

Dark Grey XDA blanks.

Next to a plateless Gnapkin.