DHT22 on Arduino Pro Mini 8Mhz 3.3V - Failed

[scalz]

Hi.

Looks like you have a communication problem between your nodes. Not really dht related. Logs show that it is searching for a parent, and no ack. Which explains why the raw examples is working ;)
Can be a power issue.
How is your node wired ?

[Puneit Thukral]

@scalz That's because I had my gateway turned off while I was troubleshooting. If you scroll down the log, the gateway goes back online and the DHT error pops up. Sorry for the confusion

[mfalkvidd]

@Puneit-Thukral there are lots of st=fail just before the dht errors, so it is most likely a power issue.

[Puneit Thukral]

@mfalkvidd What should I do ? Will adding a transistor help?

[mfalkvidd]

@Puneit-Thukral if you are not following the recommendation to use a capacitor then yes, following the recommendation will probably help.

[Puneit Thukral]

@mfalkvidd the 4.7uF capacitor is connected between ground and VCC on the radio.

[mfalkvidd]

@Puneit-Thukral ok, great.

https://forum.mysensors.org/topic/666/debug-faq-and-how-ask-for-help has a flowchart on troubleshooting power and range issues.

How is the pro mini powered? Battery? If so, what type of battery? Any regulator? Same questions for the radio and the dht.

[Puneit Thukral]

@mfalkvidd pro mini is powered through a 3.3 V power supply. There is no voltage leak ground terminals on the power supply. It measures 0 volt. Let me try everything again and I will post the results. I must also share that I used another DHT library and DHT22 test sketch on the same setup, and I was able to read data on serial interface.
I am not ruling out what you said about power issues, but just wanted to put this on the table.
I will continue to debug. Its frustrating at times, but good fun. !

[mfalkvidd]

@Puneit-Thukral the library has worked for may users, so I find it unlikely to be the culprit even though it could be the case. The larger difference is that you are not using the radio when trying the other library, right? Radio consumes power.

[Puneit Thukral]

Hi,
I changed the powersupply and tried again. Also, I checked for any loose connections.

Starting sensor (RNNNA-, 2.0.0)
TSM:INIT
TSM:RADIO:OK
TSP:ASSIGNID:OK (ID=1)
TSM:FPAR
TSP:MSG:SEND 1-1-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSM:FPAR
TSP:MSG:SEND 1-1-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSP:MSG:READ 0-0-1 s=255,c=3,t=8,pt=1,l=1,sg=0:0
TSP:MSG:FPAR RES (ID=0, dist=0)
TSP:MSG:PAR OK (ID=0, dist=1)
TSM:FPAR:OK
TSM:ID
TSM:CHKID:OK (ID=1)
TSM:UPL
TSP:PING:SEND (dest=0)
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=24,pt=1,l=1,sg=0,ft=0,st=ok:1
TSP:MSG:READ 0-0-1 s=255,c=3,t=25,pt=1,l=1,sg=0:1
TSP:MSG:PONG RECV (hops=1)
TSP:CHKUPL:OK
TSM:UPL:OK
TSM:READY
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=ok:0100
!TSP:MSG:SEND 1-1-0-0 s=255,c=0,t=17,pt=0,l=5,sg=0,ft=0,st=fail:2.0.0
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,ft=1,st=ok:0
!TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=11,pt=0,l=22,sg=0,ft=0,st=fail:TemperatureAndHumidity
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=12,pt=0,l=3,sg=0,ft=1,st=ok:1.1
TSP:MSG:SEND 1-1-0-0 s=0,c=0,t=7,pt=0,l=0,sg=0,ft=0,st=ok:
!TSP:MSG:SEND 1-1-0-0 s=1,c=0,t=6,pt=0,l=0,sg=0,ft=0,st=fail:
Request registration...
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=26,pt=1,l=1,sg=0,ft=1,st=ok:2
TSP:MSG:READ 0-0-1 s=255,c=3,t=27,pt=1,l=1,sg=0:1
Node registration=1
Init complete, id=1, parent=0, distance=1, registration=1
Failed reading temperature from DHT!
Failed reading humidity from DHT
Failed reading temperature from DHT!
Failed reading humidity from DHT

I am still stuck. Should I try another arduino and radio and sensor?

[Puneit Thukral]

I tried again with a new arduino pro mini - no luck. Then I replicated the node on an Arduino Uno and same result "Failed to read". There must be something I must be doing wrong which I can't see.

[mfalkvidd]

Strange.

I just looked through the sketch and it looks fine to me.

The st=fail during presentation is worrisome.

What is the distance between the node and the gateway? Does moving the sensor further away (>2m) or closer help?

If you can, trying another radio and sensor might be the easiest way to pinpoint the problem.

[Puneit Thukral]

@mfalkvidd Thanks for vetting the sketch.

For troubleshooting I brought the gateway and the node to the close to me (read centimeters between them).
Also, on the node on which I first discovered the error, serial print occurs at baud 230400 and on other nodes (arduinos running same sketch ) serial print occurs at baud 115200. I understand that the serial debug print should occur at 115200. Is it unexpected or odd that one arduino prints at 230400 while others are printing at 115200?

I will moving the nodes closer and away and report.

I bought 10 pro minis all 3.3v. So, for now, I think I should start something very simple. How about door close sensors? They should be pretty simple, right? If even these don't work, then either the hardware is bad or I am. Anyway, thanks a lot for your time. This is a great forum and resource and I hope I am able to foray into this amazing world of IoT.

[mfalkvidd]

@Puneit-Thukral if the baud rate is wrong, the Arduino runs at a different speed than was is selected in the Arduino IDE. Maybe you got a 5V 16Mhz instead of 3.3V 8Mhz? That could explain why the node doesn't get enough power.

[Puneit Thukral]

@mfalkvidd And the way to test that would be to input 9 v at RAW and measure the VCC, right? While I added 3.3 v to my ebay cart, the boards have 8Mhz 16 Mhz 3.3V 5V printed on them. This is what you get in India over ebay and Amazon. I trust that the seller picked and packed them correctly. I will (tomorrow) test the VCC after inputting 9 V at RAW and see if that changes anything.

[mfalkvidd]

@Puneit-Thukral good plan. That's probably the easiest way to test. It might also be possible to read the text on the regulator, but reading the small text is usually pretty hard.

[Puneit Thukral]

@mfalkvidd
The diagnosis solved the issue. The Arduino pro mini 3.3V 8 MHz sold to me was actually a 5v 16 MHz. No more Failed reading temperature from DHT!. However, there are still a few st:fail during initialisation but later goes away.
Should I work towards eliminating these or would it be fine. The Openhab2 still is not reading from this node and shows NaN (even though the sensor is online).

Thanks for your continued help.

TSM:FPAR
TSP:MSG:SEND 1-1-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSM:FPAR
TSP:MSG:SEND 1-1-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSP:MSG:READ 0-0-1 s=255,c=3,t=8,pt=1,l=1,sg=0:0
TSP:MSG:FPAR RES (ID=0, dist=0)
TSP:MSG:PAR OK (ID=0, dist=1)
TSM:FPAR:OK
TSM:ID
TSM:CHKID:OK (ID=1)
TSM:UPL
TSP:PING:SEND (dest=0)
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=24,pt=1,l=1,sg=0,ft=0,st=ok:1
TSP:MSG:READ 0-0-1 s=255,c=3,t=25,pt=1,l=1,sg=0:1
TSP:MSG:PONG RECV (hops=1)
TSP:CHKUPL:OK
TSM:UPL:OK
TSM:READY
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=ok:0100
!TSP:MSG:SEND 1-1-0-0 s=255,c=0,t=17,pt=0,l=5,sg=0,ft=0,st=fail:2.0.0
!TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,ft=1,st=fail:0
!TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=11,pt=0,l=22,sg=0,ft=2,st=fail:TemperatureAndHumidity
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=12,pt=0,l=3,sg=0,ft=3,st=ok:1.1
TSP:MSG:SEND 1-1-0-0 s=0,c=0,t=7,pt=0,l=0,sg=0,ft=0,st=ok:
TSP:MSG:SEND 1-1-0-0 s=1,c=0,t=6,pt=0,l=0,sg=0,ft=0,st=ok:
Request registration...
TSP:MSG:SEND 1-1-0-0 s=255,c=3,t=26,pt=1,l=1,sg=0,ft=0,st=ok:2
TSP:MSG:READ 0-0-1 s=255,c=3,t=27,pt=1,l=1,sg=0:1
Node registration=1
Init complete, id=1, parent=0, distance=1, registration=1
TSP:MSG:SEND 1-1-0-0 s=1,c=1,t=0,pt=7,l=5,sg=0,ft=0,st=ok:24.6
T: 24.60
TSP:MSG:SEND 1-1-0-0 s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=ok:41.9
H: 41.90
TSP:MSG:SEND 1-1-0-0 s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=ok:42.0
H: 42.00

[mfalkvidd]

@Puneit-Thukral Great work!

The failed presentation could be preventing OpenHab2 from displaying the node correctly.

Have you switched to a "real" 3.3V pro mini now or are you using the 5V? If 5V, do you use a regulator to 3.3V for the nrf?

[Puneit Thukral]

@mfalkvidd Yes, I connected the 3.3v regulator to VCC of the radio. I will continue to debug tonight. Maybe now something is amiss at the gateway side. The gateway radio is connected via dupont cables on the Uno and I am not very happy with dupont. I should solder the radio to Uno.

[Puneit Thukral]

Hi,
I believe I have been able to eliminate all the errors between node and gateway.Here is the output

Starting sensor (RNNNA-, 2.0.0)
TSM:INIT
TSM:RADIO:OK
TSP:ASSIGNID:OK (ID=2)
TSM:FPAR
TSP:MSG:SEND 2-2-255-255 s=255,c=3,t=7,pt=0,l=0,sg=0,ft=0,st=bc:
TSP:MSG:READ 0-0-2 s=255,c=3,t=8,pt=1,l=1,sg=0:0
TSP:MSG:FPAR RES (ID=0, dist=0)
TSP:MSG:PAR OK (ID=0, dist=1)
TSM:FPAR:OK
TSM:ID
TSM:CHKID:OK (ID=2)
TSM:UPL
TSP:PING:SEND (dest=0)
TSP:MSG:SEND 2-2-0-0 s=255,c=3,t=24,pt=1,l=1,sg=0,ft=0,st=ok:1
TSP:MSG:READ 0-0-2 s=255,c=3,t=25,pt=1,l=1,sg=0:1
TSP:MSG:PONG RECV (hops=1)
TSP:CHKUPL:OK
TSM:UPL:OK
TSM:READY
TSP:MSG:SEND 2-2-0-0 s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=ok:0100
TSP:MSG:SEND 2-2-0-0 s=255,c=0,t=17,pt=0,l=5,sg=0,ft=0,st=ok:2.0.0
TSP:MSG:SEND 2-2-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,ft=0,st=ok:0
TSP:MSG:READ 0-0-2 s=255,c=3,t=15,pt=6,l=2,sg=0:0100
TSP:MSG:SEND 2-2-0-0 s=255,c=3,t=11,pt=0,l=22,sg=0,ft=0,st=ok:TemperatureAndHumidity
TSP:MSG:SEND 2-2-0-0 s=255,c=3,t=12,pt=0,l=3,sg=0,ft=0,st=ok:1.1
TSP:MSG:SEND 2-2-0-0 s=0,c=0,t=7,pt=0,l=0,sg=0,ft=0,st=ok:
TSP:MSG:SEND 2-2-0-0 s=1,c=0,t=6,pt=0,l=0,sg=0,ft=0,st=ok:
Request registration...
TSP:MSG:SEND 2-2-0-0 s=255,c=3,t=26,pt=1,l=1,sg=0,ft=0,st=ok:2
TSP:MSG:READ 0-0-2 s=255,c=3,t=27,pt=1,l=1,sg=0:1
Node registration=1
Init complete, id=2, parent=0, distance=1, registration=1
TSP:MSG:SEND 2-2-0-0 s=1,c=1,t=0,pt=7,l=5,sg=0,ft=0,st=ok:22.5
T: 22.50
TSP:MSG:SEND 2-2-0-0 s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=ok:39.2
H: 39.20
TSP:MSG:SEND 2-2-0-0 s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=ok:38.7
H: 38.70
TSP:MSG:SEND 2-2-0-0 s=1,c=1,t=0,pt=7,l=5,sg=0,ft=0,st=ok:22.7
T: 22.70
TSP:MSG:SEND 2-2-0-0 s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=ok:36.6
H: 36.60

While, the node is detected at Openhab2, it remains offline. What am I missing now?
This is what I changed now

1. Re-created (fresh solder) the node on a 8Mhz 3.3V arduino pro mini
2. Changed the gateway from arduino Uno connected serial to raspberry pi gateway (mysensorsgateway). Now gateways connected as MySesnorsEthernet.
   Please help!