i have a DHT22 problem and do not know where the problem is.
I want to connect 6xDHT22 to my Raspberry Pi 2, four of them work perfectly, 2 not.
The sensors are powered by a separate 5V power supply. As cable I use Cat5E S / FTP cable.
WZ - on BCM GPIO 17 - cable length: 2m - OK
WC - on BCM GPIO 20 - cable length: 7,5m - do not work
BA - on BCM GPIO 13 - cable length: 9m - OK
SZ - on BCM GPIO 27 - cable length: 4m - OK
KU - on BCM GPIO 4 - cable length: 4m - OK
AZ - on BCM GPIO 21 - cable length: 6m - do not work
I have tested:
When i connect the DHT22 from WC to the WZ cable, the DHT22 works - so the DHT22 is not defective
There is a stable voltage of 5V.
Cable was replaced without success. Cable has also been tested separately without any other cables
PI & SD card where replaced
The longest cable with a DHT22 works - Cable length can not the failure
When i connect for example the DHT22 from WZ to the WC BCM GPIO Pin, I get values. When I Connect the DHT22 from WC to the WZ BCM GPIO Pin, I do not get any values.
I have the following stand:
Pin´s are not defective
No misconfiguration in PiMatic
cable is ok
voltage is ok
DHT22 is ok
Who has a hot tip for me? I am just helpless