Using a raspberry pi and a hall effects sensor to capture shaft rpm. this code will give me the rpm. but after a run i need to start over with zero rpm. this couter just keepd adding the rpm every test run My function code counter = flow.get("counter") || 0 counter ++ flow.set("counter, counte…

Welcome to the forum @dirtydredrt I can't see how that gives you revs per minute, it looks to me as if it is counting up the total rotation. To reset it all you need to do is to write zero to the flow variable. You can do that in a change node or in a function flow.set("counter", 0)

Thanks Colin for the fast response. flow.set("counter", 0) works great. First Node-red project... Here's my plan. Start the small 2 stroke engine (like a weed eater size) running say at 3000 rpm Using RPI 3B, I will need to have an accurate time stamp. This is an inertia dyno spinning a fly wh…

adding flow.set("counter", 0) I now just get a 1 on every count. I will need a loop to count to say 1000 and end the counter. Not sure what type of loop is needed

not finding the 'Preformatted Text' icon I can see export, will export work

It is the </> button at the top of this window where you type stuff [image]

The only area where i can find </> is inside of a function node I double click on a function node Click on discription icon then i see the </>

Just mark and copy the code in the normal way from the function node then start entering a reply in the forum and it is in the row of buttons along the top of the window where you type. Nothing to do with node-red, it is a forum feature.

flow.set("counter",0) counter = flow.get("counter") || 0 counter ++ flow.set("counter", counter) msg.payload = counter return msg; when i run this function it returns 1, never counts because at the of the flow.set("counter",0) I input a signal from a hall effects into the function node. I would…

Small engine dyno need help to reset my counter after run

General

Colin 26 March 2021 14:28 6

Post the code you now have and explain exactly what it is given and what it is supposed to do. Remember that I know virtually nothing about the what this signal you are counting represents in the real word. See this post for details of how to post code or flows - How to share code or flow json

Topic		Replies	Views
How to Reset the Counter General	23	13870	15 November 2020
YF-S201 Water Flow Sensor - Help with Require General	80	4346	25 August 2020
Need help optimising flow and Chart output General	34	2237	24 March 2019
Counting, would like some direction General	11	701	17 July 2020
Increment or decrement a value between two ranges General	24	12848	31 May 2018

Small engine dyno need help to reset my counter after run

Related topics