2 layers
Encoder
byrantech/laptop
anyon_e, a highly integrated, high end, open source laptop. Attempt the impossible.
7 parts4.3kMIT
2 layers57 × 28 mm
Json paper
trp-solutions/json-paper1Wi-Fi connected Arduino based E-Paper device showing data provided by HTTP JSON
- Size
- 57 × 28 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 7
- Nets
- 47
- Pads
- 81
- Tracks, vias
- 77, 20
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 10.0 (file 20260206)
- Created
- 1 Apr 2026
- Updated
- 26 Oct 2026
Overview
Json paper is an open-source printed circuit board by trp-solutions, from the trp-solutions/json-paper repository on GitHub, published under the Apache-2.0 licence. It is a 2-layer board of 57 × 28 mm with 7 parts on 47 nets, routed with 77 tracks and 20 vias.
Its parts include 1 IC, 1 connector and 1 switch. It belongs with the ESP32 and RISC-V boards of this library.
README
README.mdJSON Paper
See the GitHub wiki for project documentation.
Hardware
| Brand | Model |
|---|---|
| Espressif | ESP32-C5-DevKitC-1 v1.2 with 8 MB PSRAM |
| Waveshare | 5.79inch e-Paper Module (G), SKU 27846 |
Wiring
| E-paper connection | ESP32-C5 connection |
|---|---|
| PWR | GPIO5 |
| BUSY | GPIO9 |
| RST | GPIO8 |
| DC | GPIO4 |
| CS | GPIO10 |
| CLK | GPIO6 |
| DIN | GPIO7 |
| GND | GND |
| VCC (Pin 1) | 5V |
| Accessory connection | ESP32-C5 connection |
|---|---|
| Setup button | GPIO0 |
| Setup button GND | GND |
Pie charts
Use one draw_pie_slice command for each colored section. Every slice accepts:
| Argument | Meaning |
|---|---|
x, y | Center of the chart |
radius | Slice radius in pixels |
start_angle | Starting angle in degrees |
sweep_angle | Clockwise size from 1° through 360° |
color | white, black, red, or yellow |
Zero degrees points right. Angles increase clockwise: 90° points down, 180° points left, and 270° points up. Starting angles outside 0–359° are normalized. Later commands paint over earlier commands when slices overlap.
This example draws a radius-80 chart containing 25% red, 35% yellow, and 40% black:
{
"version": "1.0",
"commands": [
{
"cmd": "draw_pie_slice",
"args": {
"x": 200,
"y": 135,
"radius": 80,
"start_angle": 270,
"sweep_angle": 90,
"color": "red"
}
},
{
"cmd": "draw_pie_slice",
"args": {
"x": 200,
"y": 135,
"radius": 80,
"start_angle": 0,
"sweep_angle": 126,
"color": "yellow"
}The PHP helper provides the equivalent method:
$display
->pieSlice(200, 135, 80, 270, 90, Color::RED)
->pieSlice(200, 135, 80, 0, 126, Color::YELLOW)
->pieSlice(200, 135, 80, 126, 144, Color::BLACK);Parts
7| Qty | Value | Footprint | References |
|---|---|---|---|
| 4 | MountingHole_Pad | CIS:MountingHole_2.7mm_M2.5_Pad_Via | H1, H2, H3, H4 |
| 1 | ESP32-C5-DevKit | CIS:ESP32-C5-DevKitC-1 | U1 |
| 1 | PICO-9 | CIS:Molex_PicoBlade_1x09_P1.25mm_Horizontal | J1 |
| 1 | WS-TATV | CIS:SW_PUSH_6mm | SW1 |
Questions
How big is the Json paper PCB?
It measures 57 × 28 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Json paper use?
7 parts. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Json paper KiCad files?
From the trp-solutions/json-paper repository on GitHub, at the commit this page was made from: the board is Hardware/JsonPaper.kicad_pcb and its schematic Hardware/JsonPaper.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Json paper design in my own project?
Its repository publishes it under the Apache-2.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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