ZX81 Centronics
About the ZX81 Centronics PCB
ZX81 Centronics is an open source PCB design by BrettHallen, published on GitHub. It is a 2-layer board measuring 68.8 × 82.6 mm, with 18 components from 14 distinct parts.
Other key parts include the 74LS27, 74LS32, 74LS30 and 8255. By type, the board carries 6 capacitors, 4 ICs, 4 resistors, 1 transistor, 1 connector and 1 switch.
It belongs with the test & measurement designs in this gallery.
From the project
Projects for Sinclair computers (ZX80, ZX81, TS1000, TS1500, TS2068, Spectrum and clones)
Recreating a DIY centronics interface from German computer magazine c't.
Main components on the ZX81 Centronics
ZX81 Centronics bill of materials (BOM)
18 components, 14 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | 74LS27 | DIP-14_W7.62mm | U1 |
| 1 | 74LS32 | DIP-14_W7.62mm | U2 |
| 1 | 74LS30 | DIP-14_W7.62mm | U3 |
| 1 | 8255 | DIP-40_W15.24mm | U4 |
| 1 | BC558 | TO-92_Inline | Q1 |
| 1 | CENTRONICS | PinHeader_2x13_P2.54mm_Vertical | J1 |
| 1 | CONN_ZX81 | ZX81_EDGE | BUS1 |
| 1 | SW_Push | SW_PUSH_6mm_H4.3mm | SW1 |
| 2 | 10µF | CP_Radial_D5.0mm_P2.50mm | C1, C5 |
| 4 | 100nF | C_Disc_D4.3mm_W1.9mm_P5.00mm | C2, C3, C4, C6 |
| 1 | 10KΩ | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R1 |
| 1 | 2.2KΩ | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R2 |
| 1 | 100KΩ | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R3 |
| 1 | 4.7Ω | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R4 |
ZX81 Centronics design files
The KiCad project lives in the BrettHallen/Sinclair repository on GitHub; these links point at the commit this page was built from.
ZX81 Centronics: common questions
How big is the ZX81 Centronics PCB?
The ZX81 Centronics measures 68.8 × 82.6 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the ZX81 Centronics?
18 components, from 14 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the ZX81 Centronics design files?
From the BrettHallen/Sinclair repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the ZX81 Centronics design in my own project?
The repository has no license, so all rights stay with BrettHallen. Use it as a reference, and ask the author before reusing the design.
More boards in Sinclair
ZX80 Gaming Keyboard
276 × 89 mm49 parts2LNo license5
Z88 Expansion Connector for Keyboard
60 × 62 mm27 parts2LNo license5
ZX81 Expansion Breakout
61.2 × 53.3 mm8 parts2LNo license5
ZX80/81 Joypad
100 × 50 mm8 parts2LNo license5
Minstrel 2 v2.6 Pixel Sync Fix
45 × 18 mm7 parts2LNo license5
Minstrel 2 v2.6 Pixel Sync Fix
45 × 18 mm7 parts2LNo license5
ZX81 EPROM Upgrade
21 × 45 mm5 parts2LNo license5
ZX81 RAM Upgrade
24.8 × 36.8 mm3 parts2LNo license5
Z88 ROM to Flash ROM Converter
23 × 43 mm3 parts2LNo license5
Z88 Serial to DB25
14 × 42 mm3 parts2LNo license5
Similar boards
DB9 High-Low Signal Generator
nanographs
47 × 30 mm10 parts2LNo license370
OneInchEye
will127534
39 × 39 mm79 parts4LMIT346
Integralstick mead
azonenberg
65 × 51.5 mm19 parts4LBSD-3-Clause193
Hmcad characterization
57 × 85 mm58 parts4LBSD-3-Clause193
Iob characterization v02
74.5 × 31 mm123 parts4LBSD-3-Clause193
Pmod prbs slow
41 × 20 mm43 parts4LBSD-3-Clause193