Bulgarian open-source {hardware} specialist Olimex has begun testing of an low-cost single-board pc constructed round MOS Expertise’s iconic 6502 microprocessor, the Neo6502 — utilizing a Raspberry Pi RP2040 microcontroller to maintain the machine compact and reasonably priced.
“Lastly we managed to construct few prototypes for checks,” Olimex based Tsvetan Usunov writes of his work on the Neo6502 mission. “The delay was attributable to elements provide issues for the brand new elements in these boards which we don’t inventory. Anyway the brand new shiny purple coloration prototypes are assembled and this weekend I’ll have enjoyable.”
The Olimex Neo6502 single-board pc is almost prepared, with prototype testing and firmware improvement beginning this weekend. (📷: Olimex)
Usunov first teased the idea for the Neo6502 again in April, confessing to “a sentiment for retro computer systems.” The acknowledged aim on the time: constructing a single-board pc with a MOS 6502 at its coronary heart, for as low a price as attainable — and utilizing a Raspberry Pi RP2040 microcontroller to face in for a number of different costly chips which might in any other case be required to finish the design.
The prototype proven off by Usunov this week is predicated on the Western Design Heart (WDC) W65C02S, a contemporary surface-mount processor designed to be appropriate with the unique MOS 6502 however in prepared provide and taking over significantly much less room. The rest of the board is surprisingly gentle on built-in circuits, because of the Raspberry Pi RP2040 taking up duties like peripheral management and reminiscence provision: there’s the RP2040, after all, and three buffer chips, plus 2MB of flash storage.
The board is designed to be compact, but finds room for a header with entry to the entire 6502 bus. (📷: Olimex)
Elsewhere on the board is a piezoelectric buzzer, which might be enabled and disabled with a bodily jumper, a 3.5mm analog audio output, a USB 2.0 Kind-A Host port for a keyboard, an HDMI port carrying a DVI sign for connection to a show, a connector for accessing the 6502’s {hardware} bus, and a UEXT connector for solderless enlargement to exterior {hardware} over SPI, I2C, or UART buses.
“When these can be obtainable on the market now relies on how fast we will develop the firmware for RP2040 and W65C02,” Usunov explains. “For those who assume you may contribute to this mission you might be welcome to affix! Ship me e mail to data at olimex dot com and inform me the way you wish to assist.”
Extra data on the mission is out there on the Olimex weblog; pricing has not but been set.