2 layers245.1 × 160 mm
8-Bit CPU 32k
slu4coder/Minimal-64x4-Home-Computer
My DIY TTL home computer with VGA and PS/2 and 4x the processing power of a Commodore C64 or Apple II.
139 parts326
2 layers99.1 × 48 mm
FC AOROM UNROM
ponchick/FC-AOROM-UNROM1Multicart Famicom cartridge PCB for AOROM, AMROM, and UNROM mappers.
- Size
- 99.1 × 48 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 24
- Nets
- 76
- Pads
- 220
- Tracks, vias
- 492, 30
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 2 May 2026
- Updated
- 2 May 2026
Overview
FC AOROM UNROM is an open-source printed circuit board by ponchick, from the ponchick/FC-AOROM-UNROM repository on GitHub, published under the CERN-OHL-P-2.0 licence. It is a 2-layer board of 99.1 × 48 mm with 24 parts on 76 nets, routed with 492 tracks and 30 vias.
It is built around the 74HC161S and 74HC32D. Its parts include 5 capacitors, 5 ICs, 1 resistor, 1 diode and 1 connector. It belongs with the retro computing and games boards of this library.
Main components
2
74HC161S
SOP-160℃~+70℃ 20MHz 2V~6V 4 500mW Asynchronous Hexadecimal Counter Rising Edge Synchronous Up Counter SOP-16 Counters, Dividers ROHSGRCounters, Dividers
74HC32D
SOP-14-40℃~+125℃ 1.5V~4.2V 1.9V、4.4V、5.9V 100mV、400mV、400mV 2 2V~6V 2uA 4 5.2mA 5.2mA 500mV~1.8V 6ns@6V,50pF 74HC Series OR Gate SOIC-14 Logic Gates ROHSNexperiaLogic Gates
README
README.mdFC-AOROM/AMROM/UNROM
Multicart Famicom cartridge PCB for AOROM, AMROM, and UNROM mappers. The design closely follows work by KykuPyky (emu-land.net forum).
Russian version: README.ru.md
Features
- Up to four games on one cartridge.
- Two ways to switch games: via RESET or via an in-game menu.
- Board is intended for EEPROM or Flash memory, 4 Mbit (512 KB); UV EPROMs are not suitable. Verified with SST39SF040.
- All games must use the same mapper.
- Image size limits:
- AMROM / UNROM — up to 128 KB.
- AOROM — up to 256 KB.
Switching modes
Switching via RESET (default)
- Place parts as shown on the silkscreen.
- Solder jumpers JP6–JP9 to 1–2 (rightmost position).
This needs no special menu and works with any games.
Switching via in-game menu
- Reverse D1 (opposite polarity).
- Swap R1 and C1 positions.
- Solder jumpers JP6–JP9 to 2–3 (to the left).
- A menu example with source code is on the emu-land.net forum.
Note: With the menu you must either find unused space inside a game and embed the menu there, or dedicate one PRG-ROM bank to the menu.
Mapper compatibility
- U3 (74HC32) is used only for UNROM. For AxROM boards (AOROM, AMROM) this IC is not required.
- More on mapper families: NESdev Wiki:
Jumper settings
| Mapper | JP1 | JP2 | JP3 | JP4 | JP5 | JP10 |
|---|---|---|---|---|---|---|
| AOROM | Closed | Closed | Closed | 1–2 | Closed | Open |
| AMROM | Closed | Closed | Closed | 2–3 | Closed | Open |
| UNROM Vertical | Open | Open | Open | 2–3 | Open | 2–3 |
| UNROM Horizontal | Open | Open | Open | 2–3 | Open | 1–2 |
Jumpers JP6–JP9 select how games are switched (see above).
License
This project is licensed under CERN Open Hardware Licence Version 2 – Permissive (CERN-OHL-P-2.0).
See LICENSE.
SPDX-License-Identifier: CERN-OHL-P-2.0
Parts
24| Qty | Value | Footprint | References |
|---|---|---|---|
| 5 | SWITCH | Jumper:SolderJumper-3_P2.0mm_Open_TrianglePad1.0x1.5mm | JP4, JP6, JP7, JP8, JP9 |
| 4 | 0.1u | Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm | C2, C3, C4, C5 |
| 4 | AOROM/AMROM | Jumper:SolderJumper-2_P1.3mm_Open_TrianglePad1.0x1.5mm | JP1, JP2, JP3, JP5 |
| 2 | 74HC161 | Package_DIP:DIP-16_W7.62mm | U4, U5 |
| 1 | 10k | Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal | R1 |
| 1 | 1N4148 | Diode_THT:D_DO-35_SOD27_P7.62mm_Horizontal | D1 |
| 1 | 1n | Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm | C1 |
| 1 | 62256 | fc:DIP-28_Dual | U2 |
| 1 | 74HC32 | Package_DIP:DIP-14_W7.62mm | U3 |
| 1 | FAMICOM_EDGE | fc:CONN_EDGE_2x60 | J1 |
| 1 | LOGO | 0-Logo:ponchick | LOGO# |
| 1 | SST39SF040 | Package_DIP:DIP-32_W15.24mm_Socket | U1 |
| 1 | V/H | Jumper:SolderJumper-3_P2.0mm_Open_TrianglePad1.0x1.5mm | JP10 |
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Questions
How big is the FC AOROM UNROM PCB?
It measures 99.1 × 48 mm and has 2 copper layers, 1.6 mm thick.
What parts does the FC AOROM UNROM use?
24 parts, built around the 74HC161S and 74HC32D. 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 FC AOROM UNROM KiCad files?
From the ponchick/FC-AOROM-UNROM repository on GitHub, at the commit this page was made from: the board is FC-AOROM-UNROM.kicad_pcb and its schematic FC-AOROM-UNROM.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the FC AOROM UNROM design in my own project?
Its repository publishes it under the CERN-OHL-P-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).