ESP8266 Community Forum

- Wed Jun 10, 2015 11:04 am #20063 I was wondering if anyone could help me with an idea.

I am looking to build a circuit that when pulled high momentarily will stay high until another event pulls it low.
I think this is called a latching circuit but I'm not 100%

The reason is I want to use an ESP8266 either 01 or 03 with a tilt sensor, when tilted it will connect to the WiFi and send a Prowl alert to my iPhone. This is going to run off batteries so I need to shut the ESP down to minimise drain.

I could use an ATTiny85 to do this, pull CHP_PWD low, send the 85 to sleep and when it wakes on interrupt pull CHP_PWD high until it get's a signal on another IO pin from the ESP to say shut down again.

I was wondering however if there are any kind of passive circuits that could do this with even less power than an ATTiny85 in it's lowest possible sleep mode.


I realise it's not specifically ESP related but it might spark an idea for someone else trying to run on batteries.


Regards
Matt

- Tue Jun 23, 2015 5:38 am #21360

The reason is I want to use an ESP8266 either 01 or 03 with a tilt sensor, when tilted it will connect to the WiFi and send a Prowl alert to my iPhone. This is going to run off batteries so I need to shut the ESP down to minimise drain.
Matt

The esp8266 has a deepSleep() mode when GPIO16(XPD) is connected to reset . When it comes out of reset it runs your program from the start. So something? produces a pulse on reset it starts up from scratch sends your message and goes into deepSleep() until the next pulse. But I don't know how long a sleep time it will accept .

Pretty hard to beat the ATTiny85 I think

Get you modules here:

https://www.banggood.com/custlink/KvGGhGF4wG