08M2 Christmas Gift


Senior Member
I built this "Stranger Things" LEGO diorama for my daughter for Christmas using an 08M2 to sequence the LEDs and a 10-second sound module. I was pleased with the way it turned out, integrating the Picaxe with the sound module and getting auto-power off. Picaxe power (3V) is turned on through a 2N7000 mosfet using the sound module's pushbutton trigger to B+. Software pullups on input pin C.3 keep the power on until the LED sequence is finished, then PULLUP OFF turns off the power. 7 LEDs are individually turned on using 4 outputs C.0, C.1, C.2 and C.4 to spell RUN, AMY and MARI, after a famous scene in the series.

I used LEGO knockoffs from a dollar store. The pegs on the top and holes on the bottom were incredibly useful for accurately drilling holes for the speaker grill and switch, and potentially for an LED array as well. My "speaker enclosure" is all bricks and plates, which amplified the sound quite well. I will use these bricks again in future projects, they lend a great DIY look.

Here, my Picaxe LED code is simply timed to turn itself off using PULLUP OFF in sync with the sound chip's 10-second max duration. The sound chip includes a wired status LED, which flashes briefly when playback ends. That signal could also be read by a Picaxe pin to trigger shutdown or some other function. https://www.ebay.com/itm/141369978906

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