ESP8266 Community Forum

- Wed Jan 21, 2015 5:12 am #7851

@bicli - deep-sleep for ESP01 is possible, it's not so hard connect two esp pins together with thin wire

Thank you for your response. I'll try my best on that, but how about the other modes mentioned in the link I provided? I didn't see anywhere a possibility for setting the "standby" mode.

- Fri Jan 23, 2015 12:55 pm #8029 Espressif's just now released SDK 0.9.5, and power management got much better. If wifi_set_sleep_type(LIGHT_SLEEP_T) is set, then module most of time switches between 3 modes:

• 70mA: active receive, it's also always active when NONE_SLEEP_T is set,
• 14mA: I guess radio is down, CPU active,
• 0.7mA: radio down, CPU/mem suspended (and it resumes without restart)

Now, I don't know why 14 mA mode should be ever active, maybe it's bug. So currently module wakes up for each DTIM, spends some time in 70mA state and returns to 14 or 0.7mA state and stays there until next broadcast. For some reason amount of time in 70mA state depends on DTIM interval. With beacon interval = 500ms and DTIM=3 typical time is 100-250ms. When beacon = 100ms and DTIM=3, it drops to 40-100ms. There is one more feature: when there is a lot of traffic, module goes into 70mA mode and stays there. Broadcast traffic also counts, so module may not sleep at all! It's difficult to guess how exactly estimation algorithm works, but I'd guess that threshold is about 5-10 packets/s sustained.

On 0.9.5-b1 (current nodecmu firmware) situation was much worse, it looked like sleep_type settings had no effect at all. Well, they had, in absense of broadcasts. And there was apparently no difference between MODEM and LIGHT modes, consumption was 14mA min no matter what I tried.

That's great that Espressif guys are actively working on the firmware. Maybe in a few releases PM bugs would be cleared out.

- Sat Jan 24, 2015 6:08 pm #8122 Hello Guys,
I want to implement deep sleep and decided to buy a new ESP board because I have ESP01 (I do not feel like soldering such thin cables )). Please enumerate modules that support deep sleep (have short circuit between EXT_RSTB and XPD_DCDC). Thanks .

- Sun Jan 25, 2015 2:38 am #8138 I don't think that any module/board out there has this pre-connected. You should look for a module that has both pins exposed so you could connect them externally. The idea of espressif is that this connection should be "OR" one, maybe diode or simple resistive OR logic. This way the RST pin can be controlled from two sources - either RTC output (GPIO) or external MCU/button.
On my board (https://www.olimex.com/Products/Modules/Ethernet/MOD-WIFI-ESP8266-DEV/open-source-hardware) I have done direct connection. But this way I cannot control the reset pin like before. So I need to do a full power cycle of the module to enter serial boot mode (for flashing).

I still don't have it here (ordered several days ago) but I think that nodemcu devkit (available on aliexpress) is a good one too. It has the ESP-12 module but also add USB-UART connector and some buttons. All pins are exposed on 2.54mm pin. Here it is: http://www.nodemcu.com/index_en.html#fr_54747661d775ef1a3600009e
I hope that I am helping the nodemcu team with my order (from aliexpress), but I am not sure if this is not a clone. If thay had some mentioning of official retail channel (even aliexpress store) I would have ordered there. But now I just found the cheapest option on aliexpress.