Need help with communications

[bsj8377]

Hello all/Felix!

So I was able to get my wireless project working, however, I ran into an issue. If I lose comms between the transmitter and receiver, the receiver DAC value stays at the last value. I need to be able to write a zero to that if comms are lost

[Felix]

Hello bsj!
Maybe it's late and I'm not fully following - can you clarify this part:
"receiver DAC value stays at the last value."

Are you writing to the DAC? If comms are lost, then you cannot write to the DAC anymore?

[bsj8377]

Hey Felix!

So let me explain the application...it's a Milwaukee variable speed trigger. I wanted to be able to operate a tool remotely, so I used an old broken drill trigger, which is just a pot with a wiper that outputs 0-3.3v into the transmitter Moteino. That information gets sent to the receiver Moteino and I use the DAC to output that voltage to the control board of the tool to run it...so it's just like I'm pulling the actual tool trigger.

The issue is this...let's say I'm pulling the remote trigger and the tool is now running. If I lose comms between the two units, the receiver continues to run at the last received voltage. What I want is for it to stop the tool (write a 0 to the DAC output) if comms are lost.

Brian

[Felix]

What an interesting application 

Well then you have to determine at the receiver that you haven't received anything in XYZ amount of time, and then stop the tool / DAC / whatever runs the tool.

[bsj8377]

My brother was programming it...that's exactly what he did...lol

Works great!

[bsj8377]

[Felix]

I thought I've see it all, then ... this ... a milwaukee remote controlled by a Moteino 
I am switching to all Milwaukee myself. This will be inspiring me one day

[bsj8377]

LOL...well, I've been installing alot of industrial conduit and running wire lately...so this will enable me to both feed AND pull at the same time with one person. I picked the Moteino because it had the built in DAC, which I needed for the trigger wiper. I was trying to keep it as simple as possible with as few components as possible. There might have been a better way to do it, but this is what I ended up with. It works in testing, so I'll be taking it in the field in the next weeks, so we'll see how it does!

I plan to setup a camera on the tool so I can see when the pull is complete...maybe a prox for that in the future...

[Felix]

Ha. nice.
Well you could set a small arduino camera on the Moteino itself and send periodic images, you don't need high res (even black & white is OK) for this purpose.
In commercial applications I have the RFM69 send about 10k of data per second. This is useful for fast wireless firmware upgrades and such. So it's possible. But then maybe there's other simpler more DIY friendly and off the shelf solutions.