Pseudonymous maker “alnwlsn” has constructed the traditional reminiscence sport of Simon on a single chip — and we imply that in its most literal sense attainable, with all elements put in inside a single Microchip ATtiny84A microcontroller.
“More often than not when folks say ‘I match a sport into one chip’ that is NOT what they imply,” alnwlsn factors out of the challenge, dubbed Sub-Floor Simon. “If floor mount is mounting elements on the floor, then sub-surface mount is mounting them BELOW the floor. Any sane designer would inform you that your design will be as small because the chip package deal it is available in. This isn’t true! An IC is often only one tiny sq. minimize from a silicon wafer. Relying on the chip package deal used (and whether or not or not it has thermal properties you care about), most of a package deal is simply stamped metallic items, that are the leads of the element, and extra plastic, which will be milled away to make room for extra elements.”
Thus Sub-Floor Simon was born. The core of the sport is straightforward sufficient: the ATtiny84 chip drives 4 LEDs, which flash in a randomized sample. The participant is given the job of memorizing the sample and repeating it on 4 buttons — precisely as with Ralph Baer and Howard Morrison’s authentic toy from the Nineteen Seventies. The place the unique Simon was a chunky plastic disc, although, Sub-Floor Simon sits in the identical footprint because the microcontroller driving it — with its exterior elements sunken into the chip package deal itself.
“Milling was performed with my CNC mill, however with the motors disconnected and manually turning the knobs,” alnwlsn says of the method of getting on the chip’s inside workings, exposing the leadframe for connection to the LEDs and buttons. “The overall method I went for in meeting is to solder small wires to the leadframe with scorching air, then construct up the elements individually (doing dead-bug SMD), after which dropping the assembled block of elements into place, trimming and bending the wires over, then soldering them onto the wanted locations with a fine-tipped iron.”
The sport was assembled by hand, after milling the package deal to disclose the leadframe. (📷: alnwlsn)
“To solder wires onto the uncovered leadframe, I discovered the most effective method was to use some flux, then drop in a tiny slice of solder wire,” the maker continues. “Then, you warmth the pins externally with a scorching air gun. The warmth will journey up the pin, and soften the solder. You can’t do it by merely aiming the recent air on the solder itself, as a result of the remainder of the pin’s metallic will carry the warmth away. That is considerably counterintuitive. The identical method may also be used to cease solder from melting when you do not need it to. Clamping these pins within the vice will carry away sufficient warmth to cease the solder from melting.”
Extra particulars on the challenge can be found on Hackaday.io, together with the supply code for the sport itself — which alnwlsn describes as “nothing particular,” not like the sport’s bodily meeting course of.