pierce 2.0 is a split modular wireless / semi-wireless 36 key column staggered keyboard. The design is inspired by Corne with more pinky stagger as well as only using 1u keycaps.
It is possible to build a wireless version or a semi wireless version. If building the wireless version an additional reciever dongle is required.
In the semi wireless version the wired half is also acting as a reciever for the wireless half.
Both versions have full QMK support.
Supported switches: MX, Choc V1, Alps
The semi wireless version has a built in reset circuit for connecting a PS/2 pointing device.
There are 3 different PCBs: wireless (reversible), wired (right) and reciever.
A programmer is necessary to flash the wireless modules. A cheap option is getting an ST-Link V2 clone from ebay.
| Qty | Item | Comments |
|---|---|---|
| 2 | Pierce 2.0 wireless PCB | |
| 1 | Pierce 2.0 reciever PCB | |
| 1 | Pro micro or equivalent | |
| 2 | Keystone 3034 Coin cell battery retainer | SMD |
| 2 | 2032 3.3V Coin cell battery | |
| 3 | YJ-14015 / Core51822 (B) | |
| 3 | 1x4 pin Right-angle 2.54 mm header | For programming RF modulules. Optional, temporary soldered wires works fine |
| 2 | 4.7 kΩ resistor | SMD 1206 |
| 1 | 1117 3.3 V regulator | SMD SOT-223 |
| 1 | THT momentary switch | 2 pin THT 6 mm |
| Qty | Item | Comments |
|---|---|---|
| 1 | Pierce 2.0 wireless PCB | |
| 1 | Pierce 2.0 wired PCB | |
| 1 | Pro micro or equivalent | Elite C recommended if using trackpoint. (Pin D5 broken out) |
| 1 | Keystone 3034 Coin cell battery retainer | SMD |
| 1 | 2032 3.3V Coin cell battery | |
| 2 | YJ-14015 / Core51822 (B) | |
| 2 | 1x4 pin Right-angle 2.54 mm header | For programming RF modulules. Optional, temporary soldered wires works fine |
| 2/4 | 4.7 kΩ resistor | SMD 1206, 4 if using trackpoint, otherwise 2 |
| 1 | 1117 3.3 V regulator | SMD SOT-223 |
| 1 | THT momentary switch | 2 pin THT 6 mm |
| 1 | 100 kΩ resistor | SMD 1206 Only for trackpoint |
| 1 | 2.2 uF capacitor | SMD 1206 Only for trackpoint |
| 1 | Trackpoint module | R61 recommended, Only for.. well.. |
The soldering is pretty straight forward and it should be obvious what component goes where. If you haven't soldered SMD components before I recommend watching a youtube tutorial or two beforehand. I suggest adding a bit of solder to the middle pad for the battery holder.
The following instructions is for using an ST-Link V2 clone and Windows.
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Download and install OpenOCD from https://openocd.org/ and drivers for the programmer from https://www.st.com/en/development-tools/stsw-link009.html
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Create a file called 'openocd.cfg' in the bin folder where you installed OpenOCD with the following content:
#nRF51822 Target source [find interface/stlink-v2.cfg] transport select hla_swd set WORKAREASIZE 0x4000 source [find target/nrf51.cfg] -
Copy the relevant firmware .bin file to the bin folder where you installed OpenOCD
-
Connect the 4 pins SWCLK, SWDIO, GND and 3.3 V on the ST-Link V2 to the matching pad on the PCB and the ST-Link to the computer
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Open a command prompt, navigate to the bin folder mentioned above and enter:
openocd.exe -f openocd.cfg -
Open another command prompt and enter:
telnet localhost 4444
You should now be connected to the programmer. Enter the following commands to flash the firmware:
halt
nrf51 mass_erase
program <firmware_file_name>.bin
reset
That's it! You should now have a working pierce keyboard.
I have included files to 3D print bottom plates and switch plates (only for alps for now). The idea of the screwless bottom plates is to use a friction fit, but I'm not sure how well the current version fits.