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by CharlyDelta
Sat Jul 06, 2019 3:14 am
Forum: Camera board
Topic: RPi Cam Web Interface
Replies: 5212
Views: 1542085

Re: RPi Cam Web Interface annotate

time import sleep import Adafruit_DHT DHT_SENSOR = Adafruit_DHT.DHT22 DHT_PIN = 4 while True: humidity, temperature = Adafruit_DHT.read_retry(DHT_SENSOR, DHT_PIN) if humidity is not None and temperature is not None: print("Temp={0:0.1f}*C Humidity={1:0.1f}%".format(temperature, ...
by michelvallee
Sat Jun 29, 2019 11:55 am
Forum: Français
Topic: Vos recommandations – PI à 10 mètres des senseurs
Replies: 9
Views: 875

Re: Vos recommandations – PI à 10 mètres des senseurs

... RPi ne chauffe pas. L' autre méthode est de brancher tes capteurs sans fils ou avec des arduinos en RS-485. J'ai un exemple de capteurs DS18B20 et DHT22 sans fils avec un nrf24L01. Cela fontionne sur batterie environ 6 mois avec des AAA. https://www.raspberrypi.org/forums/viewtopic.php?f=44&t=104359&p=1158447&hilit=shockburst#p720838 ...
by michelvallee
Sat Jun 29, 2019 11:50 am
Forum: Français
Topic: Vos recommandations – PI à 10 mètres des senseurs
Replies: 9
Views: 875

Re: Vos recommandations – PI à 10 mètres des senseurs

Bjr, DS18B20 j'en ai fait fonctionner avec 30m de cable (cat5) et en mode parasite en + DHT22 le datasheet dit 20 m https://cdn.shopify.com/s/files/1/0045/8932/files/DHT22.pdf?100745 J'ai un DHT11 en 5V avec 3m de cable pas essayé + Très bonne distance... À part les ...
by totoharibo
Sat Jun 29, 2019 7:21 am
Forum: Français
Topic: Vos recommandations – PI à 10 mètres des senseurs
Replies: 9
Views: 875

Re: Vos recommandations – PI à 10 mètres des senseurs

petit problème de compatibilité : DS18B20 et DHT22 sont en 1Wire
le SW-420 est une sortie numérique donc ne peut être mis avec les autres
le SW420 tu n'en parles plus, c'est HS ?
by danjperron
Fri Jun 28, 2019 5:28 pm
Forum: Français
Topic: Vos recommandations – PI à 10 mètres des senseurs
Replies: 9
Views: 875

Re: Vos recommandations – PI à 10 mètres des senseurs

... RPi ne chauffe pas. L' autre méthode est de brancher tes capteurs sans fils ou avec des arduinos en RS-485. J'ai un exemple de capteurs DS18B20 et DHT22 sans fils avec un nrf24L01. Cela fontionne sur batterie environ 6 mois avec des AAA. https://www.raspberrypi.org/forums/viewtopic.php?f=44&t=104359&p=1158447&hilit=shockburst#p720838 ...
by JumpZero
Fri Jun 28, 2019 4:42 pm
Forum: Français
Topic: Vos recommandations – PI à 10 mètres des senseurs
Replies: 9
Views: 875

Re: Vos recommandations – PI à 10 mètres des senseurs

Bjr,

DS18B20 j'en ai fait fonctionner avec 30m de cable (cat5) et en mode parasite en +
DHT22 le datasheet dit 20 m https://cdn.shopify.com/s/files/1/0045/ ... pdf?100745
J'ai un DHT11 en 5V avec 3m de cable pas essayé +
by michelvallee
Fri Jun 28, 2019 11:26 am
Forum: Français
Topic: Vos recommandations – PI à 10 mètres des senseurs
Replies: 9
Views: 875

Vos recommandations – PI à 10 mètres des senseurs

... de la piscine (Baoblaze DS18B20) - Détection de l’arrêt/démarrage de la thermopompe (SW-420) - Température extérieure et taux d’humidité (DSD Tech DHT22 AM2302) La particularité de mon projet est la distance entre le PI et les senseurs puisque le PI est localisé dans ma remise à environ +/- 10 ...
by adellis
Tue Jun 18, 2019 7:14 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: WiringPi and I2C BME280
Replies: 5
Views: 1087

Re: WiringPi and I2C BME280

... Id reported by the Python (96 in this case). I call this once at the start and then use the check to decide whether to read from the BME280 or the DHT22. Thanks for all you help.
by adellis
Mon Jun 17, 2019 10:05 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: WiringPi and I2C BME280
Replies: 5
Views: 1087

Re: WiringPi and I2C BME280

... works fine with no BME280 connected, it just reads zero values. I was hoping something would report an error so I could fall back to using the DHT22 which is connected. I've tried a raw open("/dev/i2c-1") and then an ioctl on the I2C_SLAVE with the BME280 device id and that doesn't fail either. ...
by CharlyDelta
Mon Jun 17, 2019 12:21 pm
Forum: Camera board
Topic: RPi Cam Web Interface
Replies: 5212
Views: 1542085

Re: RPi Cam Web Interface

Now I want to get temperature and humidity (from DHT22) printed in the camera page web beside the date and the hour. How can I do this ?? Easiest way to do this is to periodically write out the temperature and humidity to /dev/shm/mjpeg/user_annotate.txt ...
by Kirikou_iot
Mon Jun 17, 2019 11:37 am
Forum: Wanted
Topic: Seeking for developper for a basic smart agriculture project
Replies: 3
Views: 3736

Seeking for developper for a basic smart agriculture project

I'm looking for someone I can pay for a basic project...Smart agriculture with Lora raspberry pi
Collect data with sensor (DHT22, ....) and send to Lora Gateway
by adellis
Sun Jun 16, 2019 10:02 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: WiringPi and I2C BME280
Replies: 5
Views: 1087

WiringPi and I2C BME280

... work is when the sensor isn't connected. The program still opens the file descriptor as if everything is fine, when I want to fall back and use a DHT22. The ic2detect -y 1 shows 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- ...
by ras07
Sun Jun 16, 2019 1:28 am
Forum: Camera board
Topic: RPi Cam Web Interface
Replies: 5212
Views: 1542085

Re: RPi Cam Web Interface

Now I want to get temperature and humidity (from DHT22) printed in the camera page web beside the date and the hour. How can I do this ?? Easiest way to do this is to periodically write out the temperature and humidity to /dev/shm/mjpeg/user_annotate.txt ...
by CharlyDelta
Sat Jun 15, 2019 2:54 pm
Forum: Camera board
Topic: RPi Cam Web Interface
Replies: 5212
Views: 1542085

Re: RPi Cam Web Interface

Ok... now I can get motor working good,

Now I want to get temperature and humidity (from DHT22) printed in the camera page web beside the date and the hour.

How can I do this ??

Thank you for your help.
by hippy
Thu Jun 06, 2019 2:48 pm
Forum: Other programming languages
Topic: ScriptBasic
Replies: 1398
Views: 97768

Re: ScriptBasic

... more time than most analysing exactly what the true situation is as best they can tell. Including Craig Ringer. His work has mostly been with DHT22's but I have seen references which suggest what he has discovered also applies or helps with DHT11 and others - http://blog.ringerc.id.au/2012/01/using-rht03-aliases-rht-22.html ...
by RichardRussell
Thu Jun 06, 2019 2:13 pm
Forum: Other programming languages
Topic: ScriptBasic
Replies: 1398
Views: 97768

Re: ScriptBasic

... (roughly) the mis-read rate, which is useful but still means retries are regularly required (and you have to wait at least a second - two with the DHT22 - before you can do so). My guess is that the worst case latency variation is just too great to guarantee recovering good data. But I know Hippy ...
by RichardRussell
Sun Jun 02, 2019 11:47 am
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 694
Views: 82000

Re: Introduction to BBC BASIC

The DHT22 needs to be supported in the code Indeed, and it is! I've REMmed out the lines for the DHT22 in the code I posted; in principle it should simply be a case of disabling the DHT11 line and enabling those two lines, ...
by bensimmo
Sun Jun 02, 2019 11:21 am
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 694
Views: 82000

Re: Introduction to BBC BASIC

... end of the stick, I thought you were trying to poll faster than it would allow, and/or worry about the heating effect at 1second polling. The DHT22 needs to be supported in the code though as it's the newer device. I was just thinking the 2second interval might be extra calculations and not ...
by RichardRussell
Sun Jun 02, 2019 11:09 am
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 694
Views: 82000

Re: Introduction to BBC BASIC

DHT22 may well be sampling differently to give it it more accurate measurement ? I don't think the DHT22 comes into this (what I have appears to be a DHT12, not a DHT22). The DHT22 is significantly different from the DHT11/12; ...
by bensimmo
Sun Jun 02, 2019 10:08 am
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 694
Views: 82000

Re: Introduction to BBC BASIC

... to make it easier to get a reliable reading. Both components are quite large. It probably the ADC whatsits that's limiting the reading rate. DHT22 may well be sampling differently to give it it more accurate measurement ?
by RichardRussell
Sat Jun 01, 2019 8:48 pm
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 694
Views: 82000

Re: Introduction to BBC BASIC

My BBC BASIC interface to the DHT11 (or DHT12, DHT22) works, but it's far from perfect: Sat. 1 Jun 2019,21:31:58 Humidity = 15.0%, temperature = 34.8C Sat. 1 Jun 2019,21:32:00 Humidity = 15.0%, temperature = 34.9C Sat. 1 Jun 2019,21:32:02 Humidity ...
by hippy
Sat Jun 01, 2019 6:07 pm
Forum: Other programming languages
Topic: ScriptBasic
Replies: 1398
Views: 97768

Re: ScriptBasic

... limit on read rates in the datasheet I have. It states here that for the DHT11 "No more than 1 Hz sampling rate (once every second)" and for the DHT22 "No more than 0.5 Hz sampling rate (once every 2 seconds)". I have to agree it says that, but there's no indication I could find of what the basis ...
by RichardRussell
Sat Jun 01, 2019 2:03 am
Forum: Other programming languages
Topic: ScriptBasic
Replies: 1398
Views: 97768

Re: ScriptBasic

hippy wrote:
Sat Jun 01, 2019 12:12 am
I couldn't see any limit on read rates in the datasheet I have.
It states here that for the DHT11 "No more than 1 Hz sampling rate (once every second)" and for the DHT22 "No more than 0.5 Hz sampling rate (once every 2 seconds)".
by John_Spikowski
Fri May 31, 2019 3:59 pm
Forum: Other programming languages
Topic: ScriptBasic
Replies: 1398
Views: 97768

Re: ScriptBasic

I wish I had the knowledge needed to do a start from scratch effort. All I want to do is get a stable GPIO extension module built and able to communicate with common used sensors.

DHT11 Resource
by bensimmo
Thu May 30, 2019 9:45 am
Forum: Other programming languages
Topic: ScriptBasic
Replies: 1398
Views: 97768

Re: ScriptBasic

... iirc has some c code. also a direct attempt at a kernel implementation, might be easier to read what is happening ? https://github.com/edwardlintw/DHT22

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