The 6502 Watch, Because Someone Had To Make One

We are very familiar with retrocomputers, and if you want you too can build a computer that could have been made in the late ’70s on a breadboard. Just grab your CPU of choice, add some RAM, some ROM, a ton of jumper wires, and give it some way to talk to the outside world. The problem with the computers inspired by yesteryear is that they all, inexplicably, use through-hole parts. If only someone used the small QFP parts instead of the big chonkin’ PDIPs, we could have really small retrocomputers. That’s exactly what [NotArtyom] did, and he managed to come up with a wearable 6502 watch.

The system design for this 6502-based watch is fairly standard for what you would find in any other retrocomputer. There’s a PLCC 6502, 32k of SRAM, 16k of ROM, and a PLLC’d 6522 for a bit of IO. There are a few peripherals hanging off the 6522, and since this thing is a watch the most important is a real time clock. There’s also a Nokia LCD and a 20-pin Commodore keyboard connector.

Software-wise, most of the ROM is dedicated to G’Mon, a generic monitor that can view and modify memory. There’s also EhBasic, and a kernel to handle the RTC, keyboard, and display.

Whether or not this is a useful smartwatch isn’t the question; this is one of the first retrocomputer projects we’ve seen that lean into the non-PDIP versions of these classic chips. This is a bit surprising, because you can still buy these parts, PDIP or not, new from the usual vendors. If nothing else, it’s a demonstration of what can be done with modern IC packages.

13 thoughts on “The 6502 Watch, Because Someone Had To Make One

          1. I work for a company that does toy invention/design work. We do a lot of work for the various toy companies(We have active products with Moose and Spinmaster, and we do work with Hasbro/Mattel fairly often, too), but our name’s only really “prominent” on one particular line of toys.

            I’m one of our three programmers, and we mostly work with 6502-based microcontrollers, because they’re generally all we can afford. We stretch 8MHz and 256 bytes of RAM to the very limits. :)

          1. Some are, some aren’t. The Furby Connect looks like it might not be(I can find references to GeneralPlus, which is a chip vendor that I’m quite familiar with, and it being able to download large amounts of content from the associated app lead me to believe it’s one of their 16-bit offerings), but anything prior to that probably is a 6502, as there wasn’t a whole lot of “content” to be downloaded/managed.

            Generally, if it doesn’t need to be recording/playing back audio, or downloading/uploading data to a phone, it’s probably either a 6502, or some 4-bit thing if it’s a /very/ simple thing. 16-bit is generally being phased out, as ARM Cortex M0’s are getting down into the same price range, and you get quite a bit more bang for your buck with an M0.

          2. If you’re really curious about what 6502-based processors are still in use, the GeneralPlus GPC3 ( ) is our workhorse, and the GeneralPlus GPCDxT is it’s up-and-coming successor ( ). Neither of those will run an LCD, but they have other chips in their lineup that can, some of which do still have a 6502 as their brain.

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