HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
<<  <  Page 2/2
mrdon
User Rank
Gold
Re: Keeping the kids safe
mrdon   7/21/2012 6:41:15 PM
NO RATINGS
Very cool and practical project. It's quite interesting to see ASM code being used eventhough C is language is common in todays embedded products. Now I have a real world example of ASM code to show my microprocessor class at ITT Tech.

armorris
User Rank
Platinum
Re: Power Lock power source
armorris   7/21/2012 10:07:20 AM
NO RATINGS

Thanks, William. I recently bought and reverse-engineered a smart outlet strip (i.e. master/slave power switch) to see how someone else solved the problems I had to solve. It used a more complex method to save standby power consumption. It used an opto-coupler and 4 diodes to switch in an extra high voltage capacitor when the relay is on to prevent burning up surplus power in the zener diode when the relay is off. BTW, the high voltage coupling capacitor provides about 20mA per microfarad of available current at 12V0VAC, 60Hz.

wgrill
User Rank
Iron
Power Lock power source
wgrill   7/20/2012 8:45:33 PM
NO RATINGS
I liked your design used in Gadget #195, much better than the one I have always used to derive appliction poiwer directly from teh line VAC. It provides a lot more flexibility in both available voltage and current. As for the code comments... comments can always be improved. I usually only comment on the major loop or function boundaries and when ever there is a user modifiable variable, table or other issue.    

Charles Murray
User Rank
Blogger
Re: Keeping the kids safe
Charles Murray   7/20/2012 6:35:00 PM
NO RATINGS
Yes, a great gadget done for a dirt cheap price. The only item of any expense is the prototype board ($12). Everything else is pennies.

armorris
User Rank
Platinum
Re: Keeping the kids safe
armorris   7/20/2012 5:54:58 PM
NO RATINGS
I responded too quickly. I see now that your ASM code does indeed have some comments in it. The code should be easy enough for someone skilled in the art to figure out, anyway.

Sorry about that! Great project!

armorris
User Rank
Platinum
Re: Keeping the kids safe
armorris   7/20/2012 5:29:38 PM
NO RATINGS
Wow! Thank you William, for using my SCR voltage regulator! I invented it back in 1978. I tried to publish it in EDN magazine back then and they didn't want it. It's loosely regulated, but it is very energy efficient. When the relay is off, you're not burning up power in a zener diode. You already know that you can add a small voltage regulator if you need more precise regulation, like for the microcontroller. You may have seen it used in three of my GF projects, GF#195, the master/slave switch, GF#198, the remote fan control and GF #218, the space heater thermostat. I have used it in a number of unpublished other gadgets that I have around the house as well. Maybe it was a good idea, after all, huh? I've had a couple of people ask me about it. At least one person appreciates it. It's also more robust against power surges than a zener diode regulator. The master/slave power switch and several other gadgets I have that use the SCR circuit have survived many thunderstorms here in Florida, including one that took out half the electronics in my house.

Yours is a great project! Some comments on your ASM code would have been nice, though.

Andrew R. Morris morr3763@bellsouth.net

Jack Rupert, PE
User Rank
Platinum
Re: Keeping the kids safe
Jack Rupert, PE   7/20/2012 3:53:50 PM
NO RATINGS
When I was young my dad used a low-tech version, although it was more of a general safety thing rather than to keep me out of it.  Basically, he wired the main outlets in the workshop through a switch mounted in a lockable box about 6' off the ground (although I dont' think the box was ever actually locked).  It box also had a red indicator bulb to remind him to shut off off workshop power when he was done.  This kept some of his older tools from being a potential hazard (fire or otherwise) when nobody was around.  Later, he upgraded the circuit to include a GFI when those things became common.

Rob Spiegel
User Rank
Blogger
Keeping the kids safe
Rob Spiegel   7/20/2012 2:21:50 PM
NO RATINGS
This is a great gadget for keeping the kids from playing with potentially dangerous tools. I would hope this is preventive safety and not locking the barn after the horse got out.

<<  <  Page 2/2


Partner Zone
Latest Analysis
Advertised as the "Most Powerful Tablet Under $100," the Kindle Fire HD 6 was too tempting for the team at iFixit to pass up. Join us to find out if inexpensive means cheap, irreparable, or just down right economical. It's teardown time!
The first photos made with a 3D-printed telescope are here and they're not as fuzzy as you might expect. A team from the University of Sheffield beat NASA to the goal. The photos of the Moon were made with a reflecting telescope that cost the research team 100 to make (about $161 US).
At Medical Design & Manufacturing Midwest, Joe Wascow told Design News how Optimal Design prototyped a machine that captures the wing-beat of a duck.
The increased adoption of wireless technology for mission-critical applications has revved up the global market for dynamic electronic general purpose (GP) test equipment. As the link between cloud networks and devices -- smartphones, tablets, and notebooks -- results in more complex devices under test, the demand for radio frequency test equipment is starting to intensify.
Much of the research on lithium-ion batteries is focused on how to make the batteries charge more quickly and last longer than they currently do, work that would significantly improve the experience of mobile device users, as well EV and hybrid car drivers. Researchers in Singapore have come up with what seems like the best solution so far -- a battery that can recharge itself in mere minutes and has a potential lifespan of 20 years.
More:Blogs|News
Design News Webinar Series
10/7/2014 8:00 a.m. California / 11:00 a.m. New York
9/25/2014 11:00 a.m. California / 2:00 p.m. New York
9/10/2014 11:00 a.m. California / 2:00 p.m. New York
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Oct 20 - 24, How to Design & Build an Embedded Web Server: An Embedded TCP/IP Tutorial
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: 10/28-10/30 11:00 AM
Sponsored by Stratasys
Next Class: 10/28-10/30 2:00 PM
Sponsored by Gates Corporation
Next Class: 11/11-11/13 2:00 PM
Sponsored by Littelfuse
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service