28 Nov
2014
28 Nov
'14
2:40 p.m.
Why not just do this the simple, usual way for an application like yours: a
pair of nice, sealed, heavy duty industrial pushbuttons marked UP and DOWN,
or even a single button with a nice heavy duty toggle switch similarly
marked?
Personally, I'd be a little leery pushing that button without knowing which
way the lift is going to move when I do...
m
----- Original Message -----
From: "Jim Brain" <brain at jbrain.com>
To: <General at classiccmp.org>; "Discussion at classiccmp.org:On-Topic and
Off-Topic Posts" <cctalk at classiccmp.org>
Sent: Friday, November 28, 2014 5:06 PM
Subject: Re: Relay question
On 11/28/2014 2:23 PM, Chuck Guzis wrote:
On 11/27/2014 11:23 PM, Jim Brain wrote:
I'm trying to wrap my mind around the problem. Does this describe it?
You want a push-on push-off circuit using only mechanical relays.
Am I reading you correctly?
--Chuck
hmm, not exactly....
To translate into electronics, it'd be like:
* Take a D FF
* hook it up in std divide by 2 mode (i.e., !Q = D)
* Take Q and attach it to a latch input with active enable line
* Take latch enable line and hook to CLK
So, on first CLK, the FF goes to 1, and the Latch allows 1 to flow out of
the unit
When CLK goes LOW, output goes to HiZ
When second CLK arrives, output goes low
When CLK goes low, HiZ
Output = 1 (hydraulic motor send lift up)
Output = HiZ (hydraulic motor off)
Output = 0 (hydraulic motor send lift down)
Jim
--
Jim Brain
brain at jbrain.com
www.jbrain.com