LisaFPGA: An FPGA Implementation of the Apple Lisa Computer

The LisaFPGA project brings the classic Apple Lisa computer to life through the innovative use of FPGA technology, offering a modernized platform for enthusiasts and developers alike. This implementation captures the essence of the original Lisa while significantly enhancing its usability with contemporary features.

Project Overview

LisaFPGA is designed to emulate both the Lisa 1 and Lisa 2/5 models in hardware, providing unique functionalities while retaining the original's look and feel. Key features include:

• Hardware Emulation: Full emulation of the Lisa environment enabling authentic computing experiences.
• Energy Efficient: With a low power consumption of approximately 2.8W, the board can run for 14-18 hours on a standard 10,000mAh USB power bank.
• I/O Compatibility: Preserves all original input/output functions except for expansion slots.
• Dynamic Memory Management: Configurable RAM from 512K to 2MB at runtime, with on-the-fly overclocking capabilities up to 3.75 times the original performance.
• High-Definition Graphics: Provides video and audio output through HDMI at 1080p resolution.
• USB Peripheral Support: Compatible with USB keyboards and mice, while also supporting original Lisa peripherals.
• Integrated Hard Disk and Floppy Drive Emulation: Features onboard ProFile hard disk emulation and a floppy drive emulator based on the ESP32 architecture.

Hardware Specifications

The hardware of LisaFPGA consists of a custom-designed 6-layer PCB integrated with a Xilinx Artix 7 100T FPGA, powered via USB-C. The board manages different voltage requirements through internal switching regulators, ensuring reliable operations across various conditions. Key hardware components include:

• USB hub sectioned into multiple interfaces for peripheral connectivity.
• External 2MB SRAM for memory, ensuring high-performance data handling.
• Onboard speaker with a faithful reproduction of the original audio output.

Building and Purchasing

Interested developers can either purchase fully assembled LisaFPGA boards from trusted retailers MacEffects or Joe's Computer Museum, or opt to build their own using provided hardware files and assembly guides. Detailed instructions for both buying and constructing boards can be found within the repository.

Firmware Programming

Programming or updating the board's firmware is straightforward, allowing users to easily keep their systems robust and up to date. Instructions are provided for both pre-programmed and self-fabricated boards, with resources available for troubleshooting firmware issues.

Getting Started

Setting up the LisaFPGA is user-friendly and involves supplying power through USB-C, connecting peripherals, and configuring the onboard SD card for hard disk emulation. The setup accommodates a variety of inputs and outputs, ensuring a seamless user experience akin to operating the original Apple Lisa.

Further Documentation

Comprehensive documentation is included in the repository, covering every aspect from initial setup to advanced configurations for connecting legacy drives and peripherals. Additional resources are available for troubleshooting and enhancements planned for future iterations of the firmware and hardware.

LisaFPGA is a project driven by the love for retro computing and FPGA technology, and it invites contributions from fellow enthusiasts looking to enrich and extend the capabilities of the classic Apple Lisa.