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Re: PIR sensor - wake and sleep using CH_PD & thingspeak upd

PostPosted: Sat Aug 27, 2016 3:47 am
by Barnabybear
Hi, I'm out for the day so I can't do any tests untill later. A small capacitor placed in parallel with the 10K resistor should help increase the time CH_PD is held high, as it can't be discharged by the PIR going low because the diode is blocking.
Be really carefull to make sure that is in parallel with the 10k, with the 1K's between it and the GPIO's or any in rush current could dammage the GPIO's when you set GPIO 0 high.

Which PIR are you using? Is there anything in the code before you set GPIO 0 high?
When tested it only need a high of 325mS to remain stable.

Re: PIR sensor - wake and sleep using CH_PD & thingspeak upd

PostPosted: Sat Aug 27, 2016 1:33 pm
by erbedo
Hi, I tried but it does not work. I am thinking that maybe either the voltage or current coming from the PIR_OUT is not enough to power the ESP8266, even though the output is HIGH.

Re: PIR sensor - wake and sleep using CH_PD & thingspeak upd

PostPosted: Sat Aug 27, 2016 4:36 pm
by Barnabybear
Hi, it looks like the PIR that you have has what is called an 'open collector' output. This means that it doesn't actualy output any voltage it only connects to ground or doesn't connect to ground.
It's going to be a little more tricky to make this work - I'll see what I can come up with.

Re: PIR sensor - wake and sleep using CH_PD & thingspeak upd

PostPosted: Sun Aug 28, 2016 3:11 am
by erbedo
I was thinking of something like that, so I tried to put a transistor activated with the PIR_OUT, which would enable CH_PD, but still no luck.