SadMac Pi HAT — Product Info
Pi Interface HAT board render

What It Does

The Pi Interface HAT replaces the Macintosh SE logic board with a Raspberry Pi 4. It drives the original CRT at 512×342 via DPI mode, routes I2S audio to the original speaker cavity, and runs Mac OS 7.5.5 through Basilisk II.

Your Mac SE becomes a fully functional System 7.5 machine — with the original screen, original sound, and original feel.

Why It's Unique

  • Only solution that preserves the original CRT with correct 60.15 Hz timing
  • Real Mac OS 7.5.5 — not a screensaver or video loop
  • Minimal wiring — just 2 connectors + power
  • Full schematics and build documentation provided
  • Full kit — PCB, all components, and hardware included

Kit Contents

PCB
65 × 56 mm, 2-layer
U1
74HCT04 Hex Inverter (DIP-14)
U2
74HC245 Bus Transceiver (DIP-20)
J2
Molex Mini-Fit Jr. 2×7 header (4.2 mm pitch)
C1–C4
100nF ceramic caps (1206)
C5
470µF electrolytic cap
R1–R2
100K resistors (1206)
FB1
Ferrite bead, 600Ω @ 100 MHz
J1
2×20 GPIO socket for Raspberry Pi
J3, J4
Pin headers (audio amp + speaker)
Hardware
4× M2.5 standoffs + 8× screws

Specifications

Board Size65 × 56 mm
Layers2
Power5V from Mac SE analog board PSU (no external supply needed)
Video512×342 @ 60.15 Hz, 1-bit, via Pi DPI
AudioI2S via MAX98357A to speaker
CRT ConnectorMolex Mini-Fit Jr., 2×7 (14 pin, 4.2 mm pitch)
Level Shifting3.3V → 5V via 74HCT04 + 74HC245
Design FilesSchematics and documentation included

v1.0 Board Errata

The first production run (v1.0) shipped with a Molex Micro-Fit 3.0 header (3.0 mm pitch) at J2. The Mac SE analog board uses a Mini-Fit Jr. connector (4.2 mm pitch). The v1.0 connector will not mate with the original cable.

Workaround: Cut the Mini-Fit Jr. plug off the original analog board cable, strip the wires, and solder them directly to the J2 pads on the back of the board. Match pin 1 (GND, black wire) to the pin 1 marking on the silkscreen. See the assembly guide for details.

v2.0 boards (current) use the correct Mini-Fit Jr. connector and accept the original cable directly.

Pricing

$35 component kit

~10 kits available in the first batch. Includes PCB and all components — you solder everything (SMD and through-hole). See the assembly guide for details.

Raspberry Pi 4 and Mac SE not included. Molex cable salvaged from original logic board.

Email to Order

Online ordering coming soon. Email rob@sadmacs.com to reserve a kit.

Assembly & Installation Guide

Read the Full Guide →