LilyPad Simple On/Off switch

Projects Discussion and Showcase E-Textiles and Craft
1

Hey all,

I am brand-new to the world of Arduino. I just hooked up my LilyPad Simple board, and I have a question.

When I change the on-board switch to "Off", the power LED goes off, but my sketch continues to run (I'm using the Blink example, with a different output pin).

What's the point of the On/Off switch if it doesn't actually stop execution/power draw? Is there a way I can turn off the LilyPad when I'm not using it, or do I need to sew on my own power switch?

Thanks!

Johnnemann

2

As shown in the schematic, that switch is actually wired to switch between battery power and the FTDI_VCC. So if you have it hooked upto to a FTDI cable, the main IC can draw power from that. Technically it's only an On/Off switch when not attached to a programmer, which for many projects would be the majority of the time (at least after they are working properly).

3

Thanks! That makes sense, and that will work just fine for what I need.

I looked at the schematic when I began this project, and frankly I can't parse it at all. Are there good resources for someone to learn how to read that?

Thanks,
Johnnemann

4

While there are some sites on-line where the information is free, the ones I've seen aren't well setup for someone initially learning to read schematics (i.e. they are mostly lists of symbols without much explanation of conventions, etc...). I would recommend getting a decent introductary electronics book, not a college level textbook although some do include this information as well many assume you know how to read. Off-hand, I can recommend some of the books by Forest M. Mims III like Getting Started in Electronics or Electronic Formulas, Symbols & Circuits. There are other worthwhile books, of course, but those two I mentioned are fairly inexpensive and many people find them very instructive.