Re: [dorkbotnyc-blabber] Looking for the right off-the shelf component

[Chris Vecchio]

Binary logic is, well, binary - either 1 or 0 and no in between.
The chips are often designed to prevent any ambiguous voltages (like 2.5).

What exactly are you trying to do?
There may be a simple analog way to do it
(like making a D/A converter with some
resistors to give you voltages in between 0 and 5V).

No switches closed = 2.5V, one switch closed = ?

     - Chris
     www.noisemantra.com


 	-------Original Message-------
  From: Alison Lewis
  Subject: Re: [dorkbotnyc-blabber] Looking for the right off-the shelf
component
  Sent: 19 Dec '08 20:48

  Lee:

Can I ask you something about these NOR gate ICs - I have one now
(74HCT4002) and its pretty easy. But what if you have three states and only
one output? I've tried a number of options, but it seems to me that I can
only get either HI or LOW outputs from this IC. I'd like to have HI, LOW,
and Middle (2.5V). I am thinking that a multiplexer is the right way to go,
but I wanted to ask you first since you seem to know pretty well.

All my best,
Alison


On Mon, Nov 24, 2008 at 11:22 AM, Lee von Kraus <[LINK:
mailto:leevonk at gmail.com] leevonk at gmail.com> wrote:
  use 'nor gate' ICs like the IC 7402

description:
[LINK: http://hyperphysics.phy-astr.gsu.edu/Hbase/Electronic/nor.html]
http://hyperphysics.phy-astr.gsu.edu/Hbase/Electronic/nor.html

where to buy:
  [LINK:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=DM7402N-ND]
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=DM7402N-ND

-Lee


On Mon, Nov 24, 2008 at 11:07 AM, Alison Lewis <[LINK:
mailto:lewischicken at gmail.com] lewischicken at gmail.com> wrote:


Hi all:

I've been asked to hack into a sensor that has four contacts (it acts
somewhat like a hand built joystick to control a moving image). Basically,
I am looking for a simple circuit that can do logic to know if any of the
four contacts are closed. If they are all open, then it should send out 2.5
Volts. I can program a PIC to do this, but I was hoping there was an off
the shelf solution out there somewhere. I was also thinking a timer could
do the trick, but I am open to other suggestions if you have any.

Thank You,
Alison


........................................................................
  .........dorkbot: people doing strange things with electricity..........
  ..........................[LINK: http://dorkbot.org.]
http://dorkbot.org............................
  ........................................................................


........................................................................
  .........dorkbot: people doing strange things with electricity..........
  ..........................[LINK: http://dorkbot.org.]
http://dorkbot.org............................
  ........................................................................


--
::::::::::::::::::::::::::::::::::::
[LINK: http://www.alisonlewis.com] www.alisonlewis.com
[LINK: http://www.iheartswitch.com] www.iheartswitch.com
  ::::::::::::::::::::::::::::::::::::

          --------------------
........................................................................
  .........dorkbot: people doing strange things with electricity..........
  ..........................[LINK:
http://dorkbot.org............................]
http://dorkbot.org............................
  ........................................................................
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://music.columbia.edu/pipermail/dorkbotnyc-blabber/attachments/20081219/7a6ab48b/attachment-0001.html