BigClown offers a lot interesting modules which you can use, but I missed WiFi connectivity – you can order module for IoT network like LoRa and Sigfox.
On the other side, this missing interface makes sense. WiFi connectivity is not low-power concept.
I accepted the higher power consumption and I designed WiFi module with popular ESP8266 IC. You can use three types of module – ESP07, ESP08 and ESP12E.
Source: https://www.bigclown.com/
The main component is popular IC with WiFi support called ESP8266 in ESP12E, ESP07 and ESP08 module.
The module is designed with focus on universality, it means:
– the choice of GPIO of Core module for controling of ESP8266 – CH_PD (P8 and P9) and RESET (P6 a P7).
– reset, IO14, IO12, IO4, IO5, IO0 and IO2 are also connected. These pins are used e.g. for I2C, boot and so one.
The ESP8266 can be controlled by AT commands (default FW) or you can upload your own FW.
Assembling and soldering
If you want to use WiFi module like interface and Core module will be the “driver” of device, assemble all components except of R6 resistor.
CH_EN (enable input of ESP8266) will be controlled by Core module (for lower power consumption).
The solder bridges are used for the choice of CH_PD and RESET from Core module It means which GPIO is used controling of signals for ESP8266.
Schematic
PCB
Reset and CH_PD
The functionality of Reset and CH_PD signals
Connection of Reset and CH_PD to Core module
Using of WiFi module like independent unit
If you want to use WiFi module independently, without Core module, assemble R6 resistor, R1 keep open.
Thus the ESP8266 will not be controlled by other board. ESP8266 will be all time in running mode.
Upload own FW to WiFi module
for uploading of own FW, follow this connection of signals
RX – TX
TX – RX
RST pin – DTR
(GPIO0) IO0 – GND
CH_PD – 3.3V
GND – GND
VCC – 3.3V
and upload your code.
Design files and examples
All design files and examples are available on https://github.com/petus/BigClown_WiFi_module
If you want the PCB, let me know.
time4ee(@)gmail.cz
