Door sensor make USB disconnect while reading serial output?

[Guilou]

@sundberg84 I use Arduino Nano V3, breadboards and NRF24L01+ with a 4.7 µF capacitor. For debugging, a use USB port from my computer or RaspberryPI. I tried with a USB charger for cellphones, and nothing seems to change (but I am blind without serial :smile: )

About software, I use Arduino IDE v1.8.5 and MySensors v2.1.1.

[sundberg84]

@guilou - everything seems fine except that nrf24l01+ is not 5v tolerant (according to specs - sometimes it works!). I recommend to exclude this problem by using a logic level converter for the datalines since the nano sends 5v over all datalines and the nrf accepts 3.3 this could be a problem.

[sundberg84]

Sorry, brainfreeze - 5v dataline should be fine... confused with the RFM radio...

[Guilou]

I use the 3v3 output of the Arduino to power the radio module :)

[sundberg84]

@guilou - should work just fine..!
But still the behaviour smells like a power issue if you use the standard sketch... did you try another radio and or nano?

[Guilou]

@sundberg84 I swapped Nano between the gateway and the sensor and this bug always occurs with the sensor sketch. I have spare radio modules, so I will try with another one, thank you for this suggestion ;)

[Guilou]

Hello,

I tried with two spares modules and I am still stuck with this curious behaviour.

[hek]

Did you try adding a larger capacitor on the radio?

[Guilou]

@hek said in Door sensor make USB disconnect while reading serial output?:

Did you try adding a larger capacitor on the radio?

Yes, but still the same.

I grab another Arduino Nano (not sure it's a guenuine one) and the serial output is correct! The sensor can not find the gateway, but this is another story :)

Do you know why some Arduino Nano V3 "compatible" will not work?

[Guilou]

Hey there,

How can I know which Arduino Nano are good for MySensors?
Mine are from Banggood and the serial output seems to be chaotic.

I have one from Gravitech and it seems to be ok…

How to choose? In the MySensors store, this is clone form Asia like mine from Banggood…

[rejoe2]

So far, most of the cheap clones I use (or used) seemed to work fine on USB side, so most likely there is no real "rule".
In case your problem is related to powering, you may replace the nano by a combination of CP2102 USB-to-serial converter and a pro mini or use a Pro Micro. The CP2102 also provides more current@3.3V (up to 100mA) and (similar to original FTDI's) allows programming of serial numbers and Product ID's to uniquely identify them in /dev/serial/by-id.

Your problem report also reminds me to problems other users had with their LAN-GW's. For them afaik downgrading the board definition for the nanos (not the IDE) to version <=1.6.11 helped a lot. You might give that a try...

[Guilou]

@rejoe2 said in Door sensor make USB disconnect while reading serial output?:

Your problem report also reminds me to problems other users had with their LAN-GW's. For them afaik downgrading the board definition for the nanos (not the IDE) to version <=1.6.11 helped a lot. You might give that a try...

Ok, I don't really understand yet what is the board definition version, but I will try. Thank you :)

[rejoe2]

@guilou said in Door sensor make USB disconnect while reading serial output?:

Ok, I don't really understand yet what is the board definition version, but I will try. Thank you :)

See Tools - Board - Boards Manager. If you click on the Board Definitions listed (here: for Arduino Nano), a dropdown with all the versions available will appear - the function is similar to the Library Manager.

[Guilou]

Hey,

Just for information: I solved all my problem ny soldering. Don't know if this is the breadboard or the Dupont wire jumpers, but with wires soldered, everything is working now :)