Turning a light on and off with momentary switch

[Peter Michelson]

There is a "10 stage LED sequencer" at the below address.
You will need to change the 555 oscillator into a
555 "one shot" circuit so you can use a pushbutton.
The 4017 can be used for just 3 LEDs by connecting the
reset line (pin 15) to the 4th output, (pin 7).

http://ourworld.compuserve.com/homepages/Bill_Bowden/page5.htm#4017-2.gif

-Bill

First question: can I use more than one stage of the LED sequencer to
prolong the duration of an LED being on? For example, if I want the first
LED to stay on twice as long as the 2nd and 3rd LEDs, is it sufficient to
connect the first two outputs to the first LED, and then only one output to
each of the other two? In other words, is it a problem to connect two
outputs together without using diodes?

Second question: I have decided to use the approach you recommended (using
the 4017 with transistors to boost the outputs, as depicted in the link
above). In order to drive the process, I would like to use a combination of
the simple toggle provided here:
http://www.terrypin.dial.pipex.com/Images/Toggles-Momentary.gif
and the 555 for automatic operation. In other words, I would like to be
able to switch back and forth between using a momentary switch to control
the LEDs and using the 555 to automatically cycle through them.
Could someone please explain the circuit design necessary for switching
back and forth between the two?

Third question: Alternatively, since the 555 can be used as a debouncer by
itself, is it possible to configure the circuit so the 555 could actually be
used both as a debouncer for manual operation and as a timer (which would
obviate the need for the simple toggle above)?

Fourth question (I think I've well exceeded my quota here): is there any
good freeware or open source software for designing circuits and printing
out those designs?

Thanks a bunch,
Peter

 

[[email protected]]

First question: can I use more than one stage of the
LED sequencer to prolong the duration of an LED being on?
For example, if I want the first LED to stay on twice as
long as the 2nd and 3rd LEDs, is it sufficient to connect
the first two outputs to the first LED, and then only one
output to each of the other two? In other words, is it a
problem to connect two outputs together without using diodes?

Yes, it is a problem, you need diodes. See my traffic light
circuit for an example:

http://ourworld.compuserve.com/homepages/Bill_Bowden/page10.htm#traffic.gif

-Bill

 

[Peter Michelson]

Yes, it is a problem, you need diodes. See my traffic light
circuit for an example:

http://ourworld.compuserve.com/homepages/Bill_Bowden/page10.htm#traffic.gif

-Bill

Perfect - thank you. Also, that seems like an elegant/parsimonious circuit
design.

Incidentally, what software do you use for rendering your circuits designs
as they appear on the links you have provided?

Thanks again,
Peter

 

[[email protected]]

Incidentally, what software do you use for rendering your

circuits designs as they appear on the links you have
provided?

The software is an old DOS program called "Colorix VGA Paint" 1989.

It's similar to Windows "Paint" with more features.
It's easy to copy and paste, and move things around.
Windows "Paint" can do the same thing, but has limited
editing features.

-Bill

 

[Peter Michelson]

The software is an old DOS program called "Colorix VGA Paint" 1989.

It's similar to Windows "Paint" with more features.
It's easy to copy and paste, and move things around.
Windows "Paint" can do the same thing, but has limited
editing features.

-Bill

Impressive. Because of the high quality, I didn't realize that you drew
them manually. I thought they were created by an electronics CAD program.

Does Colorix VGA Paint run in a DOS window on a pentium class machine?

Regards,
Peter

 

[[email protected]]

Does Colorix VGA Paint run in a DOS window on

a pentium class machine?

Yes, it runs in a DOS window on Win 95,98,2000 and
Xp. But I forgot to mention the Colorix program produces .GIF files
directly while Windows Paint only produces .BMP files which need
conversion. There are utilities to convert formats, but it's nice to
get the finished drawing in the right format without conversion
problems.

The first few drawings took some time, but as the library grew, I can
usually find a drawing close to what I need, start with that, and just
move things around to create a new drawing.

-Bill

 

[Robert Monsen]

But I forgot to mention the Colorix program produces .GIF files
directly while Windows Paint only produces .BMP files which need
conversion. There are utilities to convert formats, but it's nice to
get the finished drawing in the right format without conversion
problems.

FYI, Paint under XP can save files as GIF, TIFF, JPG, and PNG, as well
as various levels of bitmap. You need to change the popup menu on the
saveas dialog to indicate the proper format.


--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.

 

[Michael A. Terrell]

FYI, Paint under XP can save files as GIF, TIFF, JPG, and PNG, as well
as various levels of bitmap. You need to change the popup menu on the
saveas dialog to indicate the proper format.

It works the same for ME as well.