Domoticz

hi to all,
iam testing to use a pin on the gpio to use as an input in domoticz.
i connect a button (normally open) betwenn the physical pin 34 (ov) and the physycal pin 32 (name GPIO.26 and BCM 12).
in this mode when the button is unpressed, on the pin 32 i have nothing, when the buttun is pressed i must have 0v.
if i use the command gpio readall from shell i look always the value of the pin is V 0.

to export in domoticz i use a sysf gpio hardware. in the file to startup domoticz i add this line:

echo 12 > /sys/class/gpio/export

and i can add a virtual device connect to the sysf gpio on bcm 12. i set the type as contact as i find in the wiki.

i think in the export miss something, but i don't understand because from gpio readall the value is always 0.

someone can help me ?

Did you use a pull-up resistor?

SweetPants wrote: ↑Saturday 04 November 2017 16:10 Did you use a pull-up resistor?

actually i don't use nothing. tell me how restitor i must use .

guantolento wrote: ↑Saturday 04 November 2017 16:12

SweetPants wrote: ↑Saturday 04 November 2017 16:10 Did you use a pull-up resistor?

actually i don't use nothing. tell me how restitor i must use .

10K to Vcc would do, Vcc being 3.3v

10k is the value of R1 ?

i find this 2 type of connection of the gpio. how i need to use ? pullup or pulldown ?

Depends if you want the Gpio to go low (pullup) or high (puldown). Pulldown is not really a pulldown to 0V. I would choose pullup, you van always invert the action in software.

but only to make a test. can i give 3.3v directly to the gpio pin? connect directly the button (NO) between the gpio and 3.3v ?

guantolento wrote: ↑Tuesday 07 November 2017 16:50 but only to make a test. can i give 3.3v directly to the gpio pin? connect directly the button (NO) between the gpio and 3.3v ?

I don't think so, when the switch is open you have a floating input.