HardLabs

Default

barnabyosborne-cmyk·Hp42s_calc·elec/layout/default/default.kicad_pcb

Default PCB layout, top view — open source ESP32 board by barnabyosborne-cmyk

About the Default PCB

Default is an open source ESP32 PCB design by barnabyosborne-cmyk, published on GitHub. It is a 4-layer board measuring 76 × 144 mm, with 107 components from 26 distinct parts.

Its main chip is the ESP32-S2-MINI-1, from the ESP32 family. By type, the board carries 40 switches, 24 resistors, 22 capacitors, 6 ICs, 6 diodes and 3 inductors.

It belongs with the power & battery, keyboards and iot & wireless designs in this gallery.

From the project

An HP-42S-shaped calculator: e-paper display, LiPo cell, USB-C and BLE, a custom keypad PCB with metal dome switches, a resin-printed case, running Plus42 on an ESP32-S3.

An HP-42S-shaped calculator: e-paper display, LiPo cell, USB-C and BLE, a custom keypad PCB with metal dome switches, a resin-printed case, running Plus42 on an ESP32-S3.

Case dimensions follow the original HP-42S as closely as the parts allow: 148 × 80 × 15 mm.

Output lands in build/: default.net (KiCad netlist), default.csv (BOM), and a designator map. atopile does the wiring and the netlist; it does not place or route. Layout stays in KiCad.

Default bill of materials (BOM)

107 components, 26 distinct parts.

QtyPartRefs
1
?
U1
1
?
U2
1
?
U3
1
?
U4
1
?
U5
1
?
U6
1
?
Q1
1
?
Q2
1
?
J1
1
?
J2
1
?
BT1
1
?
LS1
22
?
SW1, SW2, SW3, SW4, SW5, SW6, SW7, SW8 +14
16
?
SW19, SW20, SW21, SW22, SW24, SW25, SW26, SW27 +8
2
?
SW39, SW40
4
?
D1, D2, D3, D6
1
?
D4
1
?
D5
1
?
L1
1
?
L2
Show 6 more
QtyPartRefs
1
?
L3
11
?
C1, C10, C11, C12, C13, C14, C15, C16 +3
6
?
C2, C3, C4, C8, C18, C20
5
?
C5, C6, C7, C9, C22
21
?
R1, R2, R3, R5, R6, R7, R8, R9 +13
3
?
R4, R15, R24

Default design files

The KiCad project lives in the barnabyosborne-cmyk/Hp42s_calc repository on GitHub; these links point at the commit this page was built from.

Default: common questions

What microcontroller does the Default use?

The Default is built around the ESP32-S2-MINI-1, from the ESP32 family.

How big is the Default PCB?

The Default measures 76 × 144 mm, has 4 copper layers and is 1.6 mm thick.

How many components are on the Default?

107 components, from 26 distinct parts. The full bill of materials is listed on this page.

Where can I download the Default design files?

From the barnabyosborne-cmyk/Hp42s_calc repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.

Can I use the Default design in my own project?

The repository has no license, so all rights stay with barnabyosborne-cmyk. Use it as a reference, and ask the author before reusing the design.

Can I test firmware for the Default without the hardware?

Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug ESP32 firmware against it before you order a PCB.

More boards in Hp42s_calc

Similar boards