Guess what it is and get a free PCB of it

Matseng made a contest in the forum. If you guess what the PCB is, he’ll send one over.

This PCB is exactly the same size as a credit card and have the XMega, a Lipo battery and charger, a MicroUSB for comms and charging, a buttload of tactle switches and a bunch of 7-segment displays on it. I’ll tweak the design a bit more and then send the gerbers to Seeed and see if I can get it working. Major parts of the firmware is already done for the 644 so it’s about time to actually try it on some real hardware.

I’ll send a PCB for free to the first person that correctly guesses what this project actually is meant to be.

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  1. looks to me like a tiny programmable computer. You use the keys enter commands and values in hexadecimal and use the buttons on top to start and manipulate programs. Outputs will be shown on the seven segment displays. It’s probably geared towards numerical and calculation purposes.

  2. Look like a System Development Kit, like the intel SDK-85 that I used to learn machine code eons ago…

    1. To expand on my earlier answer, I searched for the key labels: Go, St, Rs, Ad, Da, Pc and quickly turned up this. The same hex keyboard, the same alphanumeric keys, and also the same 6 displays. If this is a KIM-1 replica, then someone will doubtless be entering microchess, a chess opponent in 924 bytes of code and data and “the first game program sold for home computers”.

    2. Ding, ding ding…. And yes – we have a winner! It is (or at least hopefully will be) an emulated KIM-1.

      Send me your address to my gmail-address at mats.engstrom@…. and I’d be happy to send you a PCB when I get them from Seeed , if you like I’ll also throw in a set of the tiny 7-segment displays as well since they are not so easy to find. The other stuff on the board are just vanilla parts.

  3. What are Ad and Da? “Analog to Digital” and “Digital to Analog” If so, this might be a mini signal generator :D

  4. Go
    Program Counter

    Looks like a “front panel” of an early computer

  5. It’s a mini battery powered development board for an ATMEGA32U4. The back will have hex keys in addition to Go, Store, Reset, Address, Data, Pc and Increment. There will be 4 address and 2 data 7-segment displays.

    Looks like being a great way to learn machine code programming.

  6. I see usb aswell as 6 LED 7-seg displays at the top. Judging from the buttons on the front it’s a tool to emulate and program in assembly. I’m not exactly sure what you’ll be emulating, your own DIY CPU perhaps? :D

    display split into 2 parts. 16bit address space. 8 bit’s for data. and you have an eeprom possibly to store the programs.

  7. I’d say it’s an Arduino Leonardo with a manual hex programmer/debugger or a device to debug/program other dev boards without a PC…..

  8. Standalone debugger that lets you use the in-circut debugging features without a computer.

  9. Hi,

    I think it is not a development board because the GPIO’s are missing. It’s also not the input panel for the KIM-1 because where are the connectors to connect it? And because it has a powerful chip, the 32 bit atmega, why the need to connect it to another microcontroller?

    I think this is definitely a tool to learn about microprocessors. Because it has an address bus (Ad), a data bus (Da) and a Program Counter (Pc), I think you can emulate a Von Neumann machine with it to learn about microcontrollers. To enter sequences, see the result, and walk around the stack (The + button).

    Fun! I will definitely order one if my answer is not the best answer.


  10. I guessed it’s a KIM-1 emulator (before finding 30 comments ahead of me – LOL)…

    Nice job! It looks fantastic!

  11. As Jeff Epler guessed it it a KIM-1 emulator.

    The KIM-1 is a 6502 single board development board dating back to 1977. Having 1 KB RAM running on 1 MHz it’s not a speed demon, but it was my first computer back then that I spent countless hours on writing assembly mnemonics on paper and translating it by hand into hex codes entering it into the computer using the hex keypad and pressing go to execute it. Fun times back then when I was 12 years old.

    I still have the it in my lab, but unfortunately I’ve repurposed the 6502 and a couple of displays many years ago so I can’t use it. Maybe it’s time to restore it to it’s former glory….

    The PCB and the current state of the 6502 emulator is available on

    If anyone would like to help out with the project and have access to a PDI capable programmer, like a AVR Dragon, I’d be happy to send a PCB and the hard-to-get displays to you, but you need to supply the other parts and solder it up yourself.

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