Arduino Unstable

[NeilsenRM]

I have a Arduino Mega using the Arduino plugin that has been working flawlessly for some time with nine window and door switches. I just added three one wire temperature sensors (DS18B20) to the arduino and plugin, checked stop discovering devices, rebooted everything. The temperature sensors seem to be working fine but I'm having issues with everything else. The Arduino is having trouble connecting via the USB port, but eventually does, and the window and door sensor devices are reporting open and close status changes where there are none.

I'm powering the Arduino from the USB port. Is there a chance that the USB power is insufficient to power everything? Any other thoughts? Everything went to hell when I connected the three temperature sensors. I thought I had bumped a door or window switch wire but I ended up chasing a moving issue.

I'm going to pull the 5v power that goes to the temperature sensors to see if things stabilize. I'm also looking through my stash of wall wart power supplies for a compatible arduino power.

[NeilsenRM]

I disconnected power to the temperature sensors with no effect. Using the plugin removed the one wire pin and everything but the temperature sensors is working again.

I purchased the Arduino Mega with the idea that it could better handle more devices connected to it. Does the one wire connection require a dedicated arduino? What are the limits on connecting devices to arduino?

I'm about ready to purchase another arduino to use as a dedicated connection for the one wire sensors. I would like to get some advice? Is this necessary?

The arduino plugin manual didn't say that one wire sensors need to be connected to the digital pin but the plugin wouldn't allow anything but. I understand now that the digital pin would take considerable bandwidth and CPU power in arduino to handle the temperature sensors but you would think the Mega version of arduino could handle that and a whole bunch more.

Finally the arduino plugin didn't remove the temperature devices in HS3 and HS3 kind of warns me that the device should be deleted by the plugin. What do I do?

[randy]

I have 4 mega boards connected by Ethernet. Mine are powered by POE Ethernet shields. POE provides a net 13 watts at the board, which is just over 2A at 5V. All of them have OneWire pins, inputs and outputs. The OneWire devices are powered through the mega 5V regulators. Two of them have analog inputs and three of them have PWM outputs. All of them work perfectly.

My most populated board has more than 10 digital inputs, 15 digital outputs, a OneWire pin, 3 PWM outputs and 2 analog inputs.

I know that USB connections can offer varying levels of DC power, but I would think that even the minimum standard of 500 milliamps should be enough. If you are concerned, you could try a 1-2 amp wall wart to power the board to see if it works reliably.

[Ronnie]

I added a Arduino mega with an Ethernet shield a couple of weeks ago and it has been working perfect. I am powering the Mega/Ethernet shield with a 9v 2amp wall transformer.
Reading the spec. sheet for the Arduino Mega, it wants an input voltage from 7-12v. In my past experience feeding 5v into a 5v regulator can cause problems unless it is a step-up circuit.

Ronnie

[NeilsenRM]

I found a 1A 12V power supply and plugged that into my arduino Mega. I then tried the 1 wire sensor. As before immediately after the one wire pin is configured my door sensors became unstable. I even tried another one wire pin with the same results.

So it isn't power issue. It appears I need to purchase another arduino to dedicate as a one wire input.

Thanks for everyone's input.

Any thoughts from the arduino plugin developer?

[NeilsenRM]

I installed a second Arduino Mega and connected three temperature sensors using a one wire pin. This seems to have fixed the stability issue I had when the one wire sensors shared the arduino with my door sensors. I don't know why it was a issue but adding a additional arduino is a minor expense. The important thing was to get everything working and having reliable sensors.

[NeilsenRM]

I'm using the arduino to monitor door and window switches. On rare occasions I get a notice that one of my windows has opened when it hasn't. It appears that the status changes only for a moment. It appears that if I could have a option to report that the window was open for more than say 2 seconds before I report the open status I would be OK. I really wonder what is happening. Is this just the nature of the arduino or its plugin?

[randy]

I'm using the arduino to monitor door and window switches. On rare occasions I get a notice that one of my windows has opened when it hasn't. It appears that the status changes only for a moment. It appears that if I could have a option to report that the window was open for more than say 2 seconds before I report the open status I would be OK. I really wonder what is happening. Is this just the nature of the arduino or its plugin?

It is likely not a problem with the board or the plug-in. If you are using dry contact switches to a digital input, it is likely noise triggering the false alarm. I put a 1UF NP capacitor from the input pin to ground on short runs and one at each end on long runs. That stopped all of my false triggers.

[enigmatheatre]

I'm using the arduino to monitor door and window switches. On rare occasions I get a notice that one of my windows has opened when it hasn't. It appears that the status changes only for a moment. It appears that if I could have a option to report that the window was open for more than say 2 seconds before I report the open status I would be OK. I really wonder what is happening. Is this just the nature of the arduino or its plugin?

Randys advice is good but also what is your debounce time set to?

Greig.

[NeilsenRM]

Thanks for the input. I'm away from my home control system for 6 months and didn't get any remote access running so can't check or change.

What do I have my debounce time set to? I don't know what that is so I assume it is at stock setting. What debounce would you recommend and where is it set?

The door sensors that occasionally give a false open are configured as normally open. I would assume that they are more prone to noise. I have since planned to change them to normally closed. A capacitor would seem like a idea also. I have twenty door and window sensors and got concerned about the power drain from all the normally closed sensors.

[enigmatheatre]

What do I have my debounce time set to? I don't know what that is so I assume it is at stock setting. What debounce would you recommend and where is it set?

This is set on the config page just under where you add input pins. I have my boards set from 70 to 100 but the default is 30 so this may not help.

Greig.