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ESP-12S deep sleep resistor?

PostPosted: Fri Mar 31, 2017 2:26 am
by fred7
Hello,
I am using ESP-12F and in order to put it into deep sleep mode, I have to connect a low value resistor (330 - 1000 ohm) between GPIO16 and RESET pins. Does the new ESP-12S, especially WeMos D1 Mini ESP-12S need also that resistor?

Re: ESP-12S deep sleep resistor?

PostPosted: Sun Apr 02, 2017 5:02 am
by al1fch
Hi !
yes, all Wemos D1 mini (and D1 mini Pro) needs this resistor.
Not for going in deep sleep mode but for going out deep sleep mode.

Re: ESP-12S deep sleep resistor?

PostPosted: Sun Apr 02, 2017 7:16 am
by martinayotte
This resistor between GPIO16 and RES is needed to allow external reset while the ESP is in deepSleep.
BTW, this is true for any ESP8266.
(a shottky diode can also be use instead of a resistor)
The issue found originally is that when a simple wire was used between GPIO16 and RES, we would n't able to do a reset. The fact comes from that GPIO16 is HIGH during sleep, not tristate/open-drain, and this HIGH is stronger enough to prevent RES to be pull LOW by external device such the USB-TTL DTR/RTS circuit, and therefore, we were not able to do new firmware upload during deepSleep().

Re: ESP-12S deep sleep resistor?

PostPosted: Mon Apr 03, 2017 3:50 am
by fred7
Good to know. Thank you again!