Check out this 6-pin MSP430 microcontroller. What’s that you say? TI doesn’t make a 6-pin MSP430? True, Texas Instruments doesn’t make one, so [Greg] grabbed his Demel and a cutoff wheel, and chopped up a larger uC to arrive at this package.
It may sound a bit crazy at first, but when you think about it there’s nothing really all that special about this. The plastic package on DIP components these days is mostly empty. The silicon die which does the computing is quite small in comparison, and usually mounted in the very center of the part. [Greg] simply cut off eight of the unneeded pins (four from each end).
Well, it might be a stretch to call them unneeded since he cut the ground and voltage pins. He gets around this issue by taking advantage of the same properties of the I/O pins used in this barebones RFID tag. You can inject power through the I/O and we’d bet you could easily use this chopped-up MSP430G2211 as an RFID tag if you wanted to.
Confronted with the issue of finding a use for his mounting pile of junk electronics, [Rue] set out to build a persistence of vision device using a hardware state machine. We have a suspicion that his original link may go down if there’s too much traffic so here’s a cached link just in case.
Any board that is MSC-51 or MCS-48 based would have worked for his purposes. This is because the addressing scheme of the hardware makes it an easy hack. The image above shows him cutting off the processor from this board. It was chosen because of a 74HC373; it was a mistake at first but since it’s pin compatible with the 74HC374 that he needed a simple swap did the trick. From there a clock source was added, and the address information necessary to display the message was burned into an EEPROM.
Step twelve of his writeup shows a Morse Code message created by attaching the board to a broomstick and twirling it around in an arc. We took just a minute to decode the message and believe it’s a shout-out to Hackaday. Nice, thanks for reading [Rue]!
When [Paul Rea] started work with his current employer, he was intrigued by a traffic light that sat unused near the entrance of the “Engineering Loft” where he was stationed. He promised himself that he would get it working one day, but several years passed before he had the chance to take a closer look at it.
He took the light home with him over Thanksgiving weekend last year, and started to dig around inside to see how things were wired up. It turns out the light was a pretty simple contraption, though he discovered it ran on mains voltage, something [Paul] didn’t really want to fiddle with. He swapped out the traffic light’s bulbs for some low-voltage models, which he could easily power with a 12v wall wart.
[Paul] then added an Arduino and PIR sensor to the light fixture in order to detect when someone was leaving the Engineering Loft, warning those who are on their way in. He says that people don’t really pay attention to the light very much, though he is pretty happy with the results.
Continue reading to see a short video of the traffic light in action.
Continue reading “Stop light converted to control office foot traffic”