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The following would be to use instead of a spring-to-centre toggle switch (which I don't like).

I would like (if at all possible) to use a single push-button, which when pressed will send a short forward(?) pulse, and when pressed again will send a short reverse(?) pulse.

This would be either by the push-button having 3 (or more?) pins for common(?), A(?), and B(?), so that alternate presses would send forward/reverse pulses;

OR,

it having only 2 pins, which would send a pulse to some sort of intermediate component/circuit, which in turn would send forward/reverse pulses downstream on alternate pulses from the push-button.

Is such an idea possible, and if so, what other components would I require.

Thanks.

Deltech
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  • See my answer to [this question](https://electronics.stackexchange.com/a/374489/73158). – Transistor Feb 17 '21 at 22:35
  • How would the operator of said switch know its prior condition? With a spring to center switch the operator always knows that down is down and up is up. But with just a PB? They won't have a clue what the next press means. (You could use a short press and a long press. Then the operator would know.) – jonk Feb 17 '21 at 23:18
  • @Deltech try and write a more specific question – Voltage Spike Feb 17 '21 at 23:53
  • If the machine has that kind of fwd-stop-rev control, there's probably a reason for it. Detail? – hacktastical Feb 18 '21 at 00:25

1 Answers1

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Yes it is possible. Since you want to use only one button, which must produce a different effect (forward/reverse) according to the situation, there must be some kind of memory to make the button able to "remember" the last action it did. This memory can be implemented by means of a flip flop or a latch, which are components that maintain an state.

Something a little similar to what you want to achieve is known as a toggle button which is explained in this link. When the button is pressed, the output is a logic 1, if pressed again it goes to a logic 0.

To transform the toggle circuit to what you want, it can be followed by a couple of monostable multivibrators. One of them produces a pulse when the toggle signal goes from 1 to 0 (this could be the "reverse" signal), and the other monostable can be the opposite, produce a pulse when the toggle goes from 0 to 1.

The monostable multivibrator can be implemented, for example, with an LM555 timer integrated circuit. You can find all the information you need for this on the IC's datasheet or application notes, such as the one you can find here.

berto
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  • berto, I am very grateful for yer reply; and so quick. However, I can barely understand the circuits in the various links; and I wouldn’t know how to implement what ye said in yer reply. I COULD build the circuit if I had a diagram, so could ye be so kind as to provide one please? ALSO, the final goal downstream is to receive forward then negative PULSES on alternate presses of the push-button; NOT to receive CONSTANT forward/reverse current. Could ye please take this into account if (and I mean If) ye do provide a diagram. Thanks. – Deltech Feb 18 '21 at 00:05
  • @Deltech you are welcome, if it helped you, you can mark it as answered – berto Feb 18 '21 at 00:07
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    @Deltech the site doesn't really respond well to "Do my project for me" questions, but if you take the information you've learned here and start designing a circuit and come back with questions about that, you'll typically get a good response. If your goal is to have someone else do all the work for you, you'll have to hire an engineer. That said, a number of the ways you can accomplish your goal are fun beginner level circuits. You also haven't described your circuit well. – K H Feb 18 '21 at 06:07
  • Since your pulses are non-simultaneous, it's possible you can achieve positive and negative pulses by reverse connecting an isolated voltage source. If you're trying to work with some existing voltage source that is already referenced to ground, this would be a bad idea and you'll need a separate negative source. – K H Feb 18 '21 at 06:09
  • @Deltech you can find the circuit diagrams looking for the terms in bold font in my answer. If you have questions about that, then you can find help here as K_H mentioned. – berto Feb 19 '21 at 21:01