HOL-1 TTL CPU - ALU board
About the HOL-1 TTL CPU - ALU board
HOL-1 TTL CPU - ALU board is an open source PCB design by agben, published on GitHub. It is a 2-layer board measuring 109.2 × 78.7 mm, with 29 components from 13 distinct parts.
Other key parts include the 74LS283, 74LS86 and 74LS245. By type, the board carries 8 connectors, 8 diodes, 6 ICs, 3 capacitors, 2 jumpers and 1 resistor.
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 TTL CPU - ALU board
HOL-1 TTL CPU - ALU board bill of materials (BOM)
29 components, 13 distinct parts.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 2 | 74LS283 | DIP-16 | U1, U2 |
| 2 | 74LS86 | DIP-14 | U3, U4 |
| 2 | 74LS245 | DIP-20 | U5, U6 |
| 1 | REGISTER A LINK | pin_array_4x2 | P1 |
| 1 | REGISTER B LINK | pin_array_4x2 | P2 |
| 1 | STATUS & CTRL | pin_array_4x2 | P3 |
| 4 | DATA BUS | pin_array_8x2 | P4, P5, P6, P7 |
| 1 | Power | PIN_ARRAY_2X1 | P8 |
| 2 | Blinkenlights | SIL-9 | JP1, JP2 |
| 1 | 220Ω | r_pack8 | RA1 |
| 8 | DIODE | D3 | D1, D2, D3, D4, D5, D6, D7, D8 |
| 3 | 100nF | C1 | C1, C2, C3 |
| 1 | 47kΩ | R3 | R1 |
HOL-1 TTL CPU - ALU board 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.
- LayoutALU/Hol-1-ALU.kicad_pcb
- SchematicALU/Hol-1-ALU.kicad_sch
HOL-1 TTL CPU - ALU board: common questions
How big is the HOL-1 TTL CPU - ALU board?
The HOL-1 TTL CPU - ALU board measures 109.2 × 78.7 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the HOL-1 TTL CPU - ALU board?
29 components, from 13 distinct parts. The full bill of materials is listed on this page.
Where can I download the HOL-1 TTL CPU - ALU board 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 TTL CPU - ALU board 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.
