ESP8266 Community Forum

- Fri Mar 31, 2017 2:26 am #64434 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?

Last edited by fred7 on Mon Apr 03, 2017 3:51 am, edited 1 time in total.

- Sun Apr 02, 2017 5:02 am #64507 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.

- Sun Apr 02, 2017 7:16 am #64510 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().

- Mon Apr 03, 2017 3:50 am #64543 Good to know. Thank you again!