

Serial hat
Stuff I write for my Apple //c
- Size
- 193 × 113 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 35
- Nets
- 93
- Pads
- 223
- Tracks, vias
- 373, 5
- Pours
- 128
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 2 Dec 2022
- Updated
- 5 Nov 2026
Overview
Serial hat is an open-source printed circuit board by colinleroy, from the colinleroy/a2tools repository on GitHub. It is a 2-layer board of 193 × 113 mm with 35 parts on 93 nets, routed with 373 tracks and 5 vias.
It is built around the MAX3232ID and PC817C-S. Its parts include 9 switches, 5 capacitors, 5 connectors, 2 ICs and 1 diode. It belongs with the interfaces and adapters boards of this library.
Main components
2MAX3232ID
SOIC-16-40℃~+85℃ 2 2 250Kbps 300uA 3V~5.5V Short-Circuit Protection Transceiver Yes ±15kV SOIC-16 RS232 ICs ROHSTexas InstrumentsRS232 ICsPC817C-S
SOP-4-2.54mm-30℃~+100℃ 1 1.2V 200mV@20mA,1mA 200mW 35V 3us 4us 50% 50mA 50mA 5kV 600% 6V DC Phototransistor SOP-4-2.54mm Transistor, Photovoltaic Output Optoisolators ROHSUMWTransistor, Photovoltaic Output Optoisolators
README
README.mdRepository of stuff I write for my Apple //c
I'm having fun with this antiquity like it's 1989*!
The Apple //c was my first computer and I loved it dearly for years, but to be honest, it served little purpose these last years, only decorating the office. But then my wife woke up a monster by suggesting we do the Advent of Code, and we started, and then I thought
"I should do it with the Apple //c!"
One thing led to another and there are now quite a few things here:
- a full featured Mastodon client (homepage)
- a media player (mp3, video, webradios, ...) (homepage)
- a Peertube and Youtube client (homepage)
- a Shufflepuck clone, with two-players mode (homepage)
- a Glider clone (homepage)
- a Quicktake program, to get and view pictures from Quicktake cameras (homepage)
- an FTP client
- a Telnet client
- an HomeAssistant frontend to control switches, heating, and view sensors' graphs.
Building the Apple II programs
Install cc65:
git clone https://github.com/cc65/cc65.git
cd cc65
make
sudo make installBuild my things:
makeCreate floppy images:
make distYou can then transfer the images in dist/ using ADTPro, or putting them on a MicroSD card for your modern storage (BurgerDisk, DominoDisk, FloppyEmu, etc).
Building only the proxy
To build only the proxy, you can skip installing cc65. Install the build dependancies, then compile the proxy:
Notes
The Apple 2 serial port is port 2 by default.
Raspberry installation
For convenience, a pre-built surl-server is configured in the Raspberry image file, surl-server-bullseye-YYYY-MM-DD-lite.img.gz , available in the releases.
Copy it to a microSD card:
gunzip surl-server-bullseye-YYYY-MM-DD-lite.img.gz
dd if=surl-server-bullseye-YYYY-MM-DD-lite.img of=/dev/mmcblk0 bs=4M status=progress
syncInstall the SD card into a Raspberry, connect Ethernet, connect USB/serial adapter and boot. Everything should be up and running if you have a DHCP server.
You can ssh into the pi with the default Raspbian login, pi/raspberry. The Pi should get on the network as surl-server.local.
If you already have a running Raspberry that you'd want to use for this, you can instead add the following source and packages:
echo "deb https://apt-rpi.colino.net/debian bullseye main" | tee -a /etc/apt/sources.list.d/apt-rpi-colino-net.list
curl https://apt-rpi.colino.net/gpg.key | apt-key add -
apt update
apt install surl-server*Yes, I know it's older than that. But I got mine in 1989, when I was nine.
Parts
35| Qty | Value | Footprint | References |
|---|---|---|---|
| 5 | 100nF | Capacitor_SMD:C_0603_1608Metric | C1, C2, C3, C4, C5 |
| 4 | MountingHole_4.3mm_M4 | MountingHole:MountingHole_4.3mm_M4 | MH2, MH5, MH7, MH8 |
| 3 | MountingHole_2.7mm | MountingHole:MountingHole_2.7mm | MH1, MH3, MH4 |
| 2 | , | ||
| 1 | 4PDT 12 pins Piano Switch | Colins-Kicad:4PDT 12 pins Piano Switch | Unpopulated |
| 1 | Conn_01x02_Pin | Connector_PinHeader_2.54mm:PinHeader_1x02_P2.54mm_Vertical | J3 |
| 1 | ImageWriter | Colins-Kicad:MINI-DIN8-F C20611694 | K2 |
| 1 | LED | LED_SMD:LED_0603_1608Metric | D1 |
| 1 | MAX3232 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U1 |
| 1 | Modem To Proxy | Colins-Kicad:4PDT 12 pins Piano Switch | SW1 |
| 1 | Modem out 3 | Colins-Kicad:DIN-5-M C23689428 | CN2 |
| 1 | Modem out 3 | Colins-Kicad:4PDT 12 pins Piano Switch | SW3 |
| 1 | Modem port | Colins-Kicad:DIN-5-M C23689428 | CN1 |
| 1 | Modem to Quicktake | Colins-Kicad:4PDT 12 pins Piano Switch | SW2 |
| 1 | PC817C-S | Colins-Kicad:PC817C-S C3008369 | U2 |
| 1 | Printer port | Colins-Kicad:DIN-5-M C23689428 | CN3 |
| 1 | Printer to ImageWriter | Colins-Kicad:4PDT 12 pins Piano Switch | SW6 |
| 1 | Printer to Proxy | Colins-Kicad:4PDT 12 pins Piano Switch | SW5 |
| 1 | Quicktake | Colins-Kicad:MINI-DIN8-F C20611694 | K1 |
| 1 | Rpi headers | Connector_PinSocket_2.54mm:PinSocket_2x20_P2.54mm_Vertical | J1 |
| 1 | SW_SPST | Colins-Kicad:SPST momentary switch C6575016 | SW7 |
| 1 | SW_Slide_DPDT SHOU HAN MSK-22D18G4 051 | Colins-Kicad:DPDT slide switch C7507433 | SW8 |
The 32 most common of 35 parts.
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Questions
How big is the Serial hat PCB?
It measures 193 × 113 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Serial hat use?
35 parts, built around the MAX3232ID and PC817C-S. 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 Serial hat KiCad files?
From the colinleroy/a2tools repository on GitHub, at the commit this page was made from: the board is PCBs/integrated-serial-device/serial-hat.kicad_pcb and its schematic PCBs/db25-din5-adapter/db25-din5-adapter.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Serial hat design in my own project?
Its repository states no licence, so its author keeps all rights: ask colinleroy before reusing the design.