Unisoc’s RDA5981 and MediaTek’s MT7697 microcontrollers (as well as variants of these two) also incorporate a WiFi radio on the chip and target low-power embeded IoT applications.
Is the RTL8710 faster at waking up and connecting to a Wifi network than the Espressif microcontrollers?
Open Network The sketch used for this test is very simple: connect to the open Wifi network, connect to a local server using TCP and send a short message, then go back to sleep.
The RealTek RTL8710 is pitched directly at the esp8266 and it even comes in an RTL-00 module that has the same pinout as an esp-12f module. How does it fare at low-power Wifi?
Experimental set-up RTLDuino with an RTL-00 Module which houses the RTL8710AF ARM Cortex-M3 Microcontroller.
With a few more hacks the esp32 light-sleep power consumption can be pushed to the limit. This post explores the limit and calculates light-sleep mode run-times.
The esp32 can also maintain an association with an access point while going to sleep on its own when it is idle. Is this a good alternative to periodically waking up from deep-sleep?
Updated 2019-08-25 to include EzSBC’s ESP32-01 Breakout and Development Board
In order to test the low-power performance of the esp32 I had to acquire a few boards and I didn’t really like any of them.
Periodically waking up from deep sleep and sending a short TCP message is interesting, but how does the esp32 perform in a real scenario where it communicates with an MQTT server?
The long probing for the access point can be optimized away. In addition, it’s not smart to use open access points, so it’s time to measure the cost of security!
The esp32 is the successor of the esp8266 by Espressif. It is much faster, has two cores, more memory, more I/O, more everything. Does it also have more low-power Wifi mojo?
Instead of disconnecting from the AP before going to sleep and then reassociating it is also possible to maintain the association while going to sleep.
Operating Wifi at low power is difficult, Wifi is just way more complex and chatty than simple RF links. This project and blog post series explores what is available at the end of 2018.
Light barrier using pulsed IR. The transmitter is based on NE555 timers and the receiver on a special-purpose IR receiver, an stm32 for control, and an rfm69 radio to transmit interruptions.
Solar powered light barrier across a driveway to signal the entrance and departure of vehicles and pedestrians using a door chime. Communication between the light barrier and the chime is via RF links and MQTT.
I spent some time this week troubleshooting the LoRa communication problems I encountered when testing long range links from the ocean sports tracker. It led me to the SPI bus…