(Update !!! CP/M 2.2 for the MakerLisp Machine is released ! See the release notes and archive on the Download page at http://makerlisp.com/download)

What is it?

A business card (2" x 3.5") sized single board computer, based on a 50 MHz Zilog eZ80. It is the CPU for the "MakerLisp Machine", a vintage-styled personal computer with Lisp in ROM, which can also run CP/M. The CPU can be used stand-alone, connected to a terminal emulator on a computer, or it can plug into an expansion board as part of a complete system, including VGA display controller, USB keyboard controller, and laser cut wood enclosure. A FAT32 micro-SD card on the board provides storage for your programs and data.

The CPU card, and all of the optional boards offered here, are fully assembled. All of the system software for these boards is open source, freely and publicly available at makerlisp.com.

Why did you make it?

This is the system I wanted for myself, and I think other people might like it too. I miss the simplicity, the immediacy, and the reliability of the personal micro-computers of the late 70's and early 80's. And I also think this machine might provide a better, more distraction-free environment for young students learning the fundamentals of computers and software.

What makes it special?

The MakerLisp system in ROM is a "Lisp on Bare Metal", requiring no OS, and giving direct access from your Lisp programs to the eZ80 registers and peripherals. So you can do Arduino kinds of things, on a more powerful processor, programming in a self-hosted Lisp environment - no cross-development, no downloading and reprogramming of flash ROM necessary. MakerLisp is a practical mix of Scheme, Common Lisp, and C, designed for machines like this - I made the software system I wanted for the machine I wanted, and vice versa.

The 50 MHz eZ80 is also a terrific engine for CP/M and CP/M programs - the CP/M port is now complete, and many programs have been tested. The CP/M BIOS, BDOS, and CCP live in flash ROM. The same "live update" flash tool that has been provided previously, to install updates to the Lisp system software, can be used to load the alternative CP/M ROM firmware. A demonstration CP/M disk volume is also provided on the MakerLisp SD card image, so you can boot and try CP/M right away. And you can then re-load the Lisp system ROM and flip back to MakerLisp just as easily, from CP/M.

With the optional I/O expansion board, you can use the standard Zilog C language IDE and debugger/programmer tools, so you can also develop software as you would for any other embedded cross-development target. This system is a fast, inexpensive, convenient platform for eZ80 development - and there just aren't that many eZ80 boards out there.

Options:

I/O expansion: The I/O expansion board provides a barrel jack, and header pins, for additional external power sources. Regulated 5V and 3.3V power, and access to all 32 eZ80 GPIO/peripheral inputs and outputs, is provided through header pins for use by optional boards and your bread-boarded circuits. Everything on the board and everything downstream can be powered through the USB connector on the CPU card, OR a power input to the expansion board, but the I/O expansion also contains an automatic power-switching feature. If both the CPU USB and an I/O expansion power source are connected, the I/O expansion source takes priority and shuts off the USB power connection. No jumper configuration is required, and you can't damage the boards or back-power a USB power source, no matter how you hook it up.

USB Keyboard: The USB keyboard controller is a USB HID keyboard controller host, which can manage input from most common USB keyboards. It's based on a Microchip PIC32MM micro-controller, and acts as the keyboard side of an ANSI terminal, sending characters to the CPU over a 115200 baud serial connection.

VGA Display: The VGA display controller drives virtually any VGA monitor, to provide a 30 row by 80 column display of 9x16, code page 437 extended ASCII text and graphic characters. The board is based on the Parallax Propeller micro-controller, for which a wealth of free software is available. The VGA controller acts as the display portion of an ANSI terminal, receiving characters from the CPU over a 115200 baud serial connection.

Enclosure: The "Maker Station" custom designed laser cut wood enclosure houses your MakerLisp boards, keyboard, monitor, and cables. This enclosure provides easy access to boards for wiring and observation while in use, and keeps all components and accessories conveniently located for storage between uses. The Maker Station is made from 1/8" poplar plywood and includes a project board to hold all four MakerLisp boards, a keyboard tray and monitor shelf. A cable pouch holds your cables and other accessories when not in use. The project board flips over, with all boards facing down into the storage bay, so the monitor can be placed on top, glass down, and strapped in place, for carrying (see pictures above, or video below). The keyboard tray measures 9 3/4" wide by 3 5/8" deep and is designed to accommodate a Vortex Core mechanical keyboard. The monitor shelf measures 10 1/2" wide by 6 5/8" deep, and fits an Elecrow 10.1" model AUS50024E HDMI/VGA display monitor.

Important Notes: Although pictured above, no keyboard, monitor, breadboards, or cables are included. The CPU card uses a CR1632 battery, and an SDHC micro-SD card, neither of which are included, but both of which are widely available in stores. Consult the documentation in the source archive, or contact MakerLisp, for information on monitors, keyboards, and accessories which work best with this product.