Everything Old Is New Again: Another 6502 Board Is Born

[Jeff] says that designing your own 6502 computer is a rite of passage, and he wanted the experience. His board can accept a real 6502 or the newer CMOS variant that is still available. There are a few modern conveniences such as USB power and provisions for using a USB serial port.

We are spoiled today with microcontrollers having everything in one package, but with this class of CPU you need your own memory, I/O devices, and other support chips. [Jeff] took a traditional approach, but picked components that are still easy to obtain. Some designs now push all the support functions to a more modern processor like an Arduino, which is very simple to do, but doesn’t feel as authentic, somehow.

For software, there are several versions of BASIC, one based on Ohio Scientific’s variant. There’s also a monitor image. With 32K of RAM, this would have been a respectable machine in its day. The BASIC interpreter dates from 1977. There are plenty of old BASIC games from those days and [Jeff] shows a famous version of poker running on the board. The 6502’s assembly language isn’t that bad, either.

We love these old retro builds. If you don’t fancy all the support chips you can, as we mentioned, use another processor. Or, try an FPGA.

8 thoughts on “Everything Old Is New Again: Another 6502 Board Is Born

    1. Here, hold my coffee..

      2MHz max clock (1.832 on board)
      32K static RAM
      16K ROM via 27128 UV erasable
      Serial via a 6850 through an external FTDI-USB
      6522 VIA broken out to header
      No native video generation

  1. 6502/65C02 can be a lot of fun. The instruction set is very RISC-like in many ways being a single-address architecture. They could be a lot more fun at 16 or 20 MHz and with no-wait static RAM.

    What is available these days for fast 6502? Accelerators in the 1980’s topped out at 10MHz IIRC and the Western Design has a 65C02 at 14MHz possibly doing 18 or 20MHz (https://www.westerndesigncenter.com/wdc/w65c02s-chip.php). Maybe some gate array implementations that are faster?

  2. There’s nothing I like seeing more than another 6502 board, let alone one that runs both the original chips or CMOS!
    It’s also a pleasure to read the words “Ohio Scientific” these days, top hackaday article 10/10.
    (This is the part where I end up re-reading all the other articles tagged 6502 here, or spend the rest of the day tinkering with my own boards…)

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