Hol-1 8-bit CPU - Registers A, B and C
About the Hol-1 8-bit CPU - Registers A, B and C PCB
Hol-1 8-bit CPU - Registers A, B and C is an open source PCB design by agben, published on GitHub. It is a 2-layer board measuring 109.2 × 78.7 mm, with 26 components from 12 distinct parts.
Other key parts include the 74LS245 and 74LS173. By type, the board carries 9 ICs, 8 connectors, 6 capacitors and 3 jumpers.
From the project
Homebrew 8-bit TTL CPU
HOL-1 a homebrew 8-bit TTL CPU --- HOL-1 is a TTL based 8-bit CPU based on the 'simple as possible' breadboard design by Ben Eater https://eater.net/8bit/
As well as adding my own modifications to each module of this CPU. i.e. - more memory - more registers - more ALU functions - more commands (assembler code to follow)
The main change is that HOL-1 is designed for permanent construction using common 8cm x 12cm double-sided perfboards.
Main components on the Hol-1 8-bit CPU - Registers A, B and C
Hol-1 8-bit CPU - Registers A, B and C bill of materials (BOM)
26 components, 12 distinct parts.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 3 | 74LS245 | DIP-20 | U1, U2, U3 |
| 6 | 74LS173 | DIP-16 | U4, U5, U6, U7, U8, U9 |
| 1 | DATA BUS | pin_array_8x2 | P1 |
| 1 | REG-A-CTRL | PIN_ARRAY_2X1 | P2 |
| 1 | REG-B-CTRL | PIN_ARRAY_2X1 | P3 |
| 1 | REG-C-CTRL | PIN_ARRAY_2X1 | P4 |
| 1 | POWER | PIN_ARRAY_2X1 | P5 |
| 1 | CTRL-ALL | PIN_ARRAY_2X1 | P6 |
| 1 | REGISTER A LINK | pin_array_4x2 | P7 |
| 1 | REGISTER B LINK | pin_array_4x2 | P8 |
| 3 | Blinkenlights | SIL-9 | JP1, JP2, JP3 |
| 6 | 100nF | C1 | C1, C2, C3, C4, C5, C6 |
Hol-1 8-bit CPU - Registers A, B and C design files
The KiCad project lives in the agben/Hol-1 repository on GitHub; these links point at the commit this page was built from.
Hol-1 8-bit CPU - Registers A, B and C: common questions
How big is the Hol-1 8-bit CPU - Registers A, B and C PCB?
The Hol-1 8-bit CPU - Registers A, B and C measures 109.2 × 78.7 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Hol-1 8-bit CPU - Registers A, B and C?
26 components, from 12 distinct parts. The full bill of materials is listed on this page.
Where can I download the Hol-1 8-bit CPU - Registers A, B and C design files?
From the agben/Hol-1 repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.
Can I use the Hol-1 8-bit CPU - Registers A, B and C design in my own project?
The repository has no license, so all rights stay with agben. Use it as a reference, and ask the author before reusing the design.
