This Guy Is Building a Dream 6502 Retro Laptop

There were two processors that dominated the home computer market of the late ‘70s and early ‘80s: the Zilog Z80 and the MOS Technology 6502. Both were 8-bit processors with fairly comparable performance. The 6502 was first introduced in 1975 and had clock speeds between 1 MHz and 3 MHz, and was used in many of the most popular computers of the era. Those include the Apple II, the Commodore 64, the BBC Micro, and the Atari 8-bit Family. But most early portables utilized the Zilog Z80 processor. Adam.klotblixt decided to address that and build his own dream 6502 retro laptop called the PZ1.

Many of our younger readers probably wouldn’t even recognize this as a laptop, but it is actually very similar to the portable computers of the early ‘80s, such as the TRS-80 Model 100 and the Epson HX-20. Computers like those were mostly keyboard, with just a tiny little monochrome LCD screen capable of showing a few lines of text. Adam is seeking to recreate that form factor, but with the iconic MOS Technology 6502 processor in place of the more common “portable” processors from that era. While he’s at it, he’s throwing in extras like a healthy 256kb of RAM.

Purists may be disappointed, but Adam is not using an actual MOS Technology 6502 processor in this PZ1 project. Instead, he’s using a Teensy 4.0 to emulate the 6502 and most of the rest of the hardware. But, in his defense, he’s only emulating the kind of hardware that would have been available at the time — even if it would have been very expensive. In addition to the Teensy, Adam is using an Arduino Nano board. That’s used to interface with the Cherry G84-4100 compact PS2 keyboard and LCD. Text is shown on a 40x4 character monochrome LCD screen. An SD card is used for storage and a pair of 18650 LiPo batteries provide power. This project is still in progress, but Adam does already have the basic functionality working.