Anybody with a Raspberry Pi? [Testing DHT11 on Banana Pi]

[GeorgeC]

Hello,

I would like to test a temperature-humidity sensor DHT11 on a Raspberry Pi.

I tried that with a Banana Pi (the Chinese copy of Raspberry Pi), but after reading the first couple of bits it gets stuck.
Not sure if that is due to the board GPIO or the sensor...

If we manage to read the data from DHT11 with a Raspbery board, that means the BananaPi GPIOs are not ready yet :)


 

[Panayiotis]

Hi George,

I have one available! (Model B, rev.1)

Panayiotis

[GeorgeC]

Great, will contact you.

[GeorgeC]

Just not to leave here a bad impression about Banana Pi :D

I have done some tests on GPIOs and compared the Banana Pi with a Raspberry Pi B. Thanks to Panayiotis for the board ;)

Until now I was using Raspbian v3.0 on Banana Pi, and there was that problem when reading data from the sensors. 

But everything seems to be fine with the recent updated version of Raspbian v3.1 release for Banana Pi. 

Actually the release notes mention about a wiringPi update, and indeed, it is a big updated which improves performance on Banana Pi (may be even better than on Raspberry Pi).

Here are the results:

The piece of code I was testing is:

    t4S = micros();    

    pinMode( DHTPIN, INPUT );    // Set pin to input

    digitalWrite( DHTPIN, HIGH ); // Set pin to high

    t4E = micros();

and get the difference between t4E and t4S to see how much time it pends on these operations:

Raspberry Pi B:

pi@raspberrypi ~ $ sudo ./TestTemp

Raspberry Pi wiringPi DHT11 Temperature test program

T1 [11]

T1 [9]

T1 [9]

T1 [10]

T1 [10]

Banana Pi Version: 3.0 

bananapi@lemaker ~/Sensors $ sudo ./TempTest

Raspberry Pi wiringPi DHT11 Temperature test program

T1 [658]

T1 [409]

T1 [512]

T1 [578]

Banana Pi Version: 3.1 (Release date:2014-08-12)

bananapi@lemaker ~/Sensors $ sudo ./TempTest9

Raspberry Pi wiringPi DHT11 Temperature test program

T1 [7]

T1 [6]

T1 [6]

T1 [6]

T1 [9]

T1 [6]

Not bad at all!!! :D