The Apple I used to be an influential step in private computing historical past. Clones of it have grown in recognition since actual machines are uncommon (and costly.) As an alternative of making one more clone, retro-computer fanatic Chris Davis took a unique strategy. The AC-1 is a reimagined Apple I with a 6502 at its core with trendy microcontrollers supporting it.
The AC-1 circuit board comprises RAM, ROM, a Peripheral Interface Adapter, glue logic, and several other microprocessors. A Western Design Middle (WDC) 65c02 runs the eight-bit Wozrom and BASIC code. Fashionable interfaces can be found by way of a Microchip PIC32 and an Arduino Nano.
AC-1 (📷:Adwater & Stir, Tindie)
The PIC32 has two duties: USB keyboard enter and VGA video output. It communicates with an Arduino Nano. The Nano connects to the 65c02’s information bus by way of an MCP23517 I/O Expander. The Arduino additionally supplies an interface to an SD card.
In contrast to the unique Apple I, BASIC is out there in ROM. Which suggests the pc is able to use after it boots. You possibly can load BASIC applications from the SD card. The ROM additionally comprises Wozmon, which is a monitor program. In older computer systems, the monitor lets you view or change reminiscence contents. Some even allowed for assembling and dissembling brief applications.
AC-1 with VGA monitor and USB Keyboard (📷: Adwater & Stir, Tindie)
In some methods, this package is paying homage to the RetroShield. The challenge used an actual 6502 (or Z80) processor linked to an Arduino Mega emulating classic computer systems’ logic. AC-1, nonetheless, higher reassembles the unique Apple I with its handful of ICs cleanly laid out on a printed circuit board.
General, AC-1 does a unbelievable job of augmenting classic applied sciences with trendy parts. Davis designed the package solely with through-hole parts, which ought to make soldering extra accessible to these new to soldering.
Davis says the challenge is absolutely open supply, though the GitHub repository (presently) lacks design recordsdata past a PDF of the schematic. Regardless that you should purchase the AC-1 as an assembled package, the meeting and operations handbook does comprise important documentation.
A totally assembled AC-1 is out there for $129 earlier than delivery.