New comer in the Sigfox ecosystem : the Wisol FM20R1.
Wisol have already changed the Sigfox module world by providing a solution based on the OnSemi design for transmitting on Sigfox network for about 2$. Now they are back with a full SoC solution for a really competitive price estimated under 15$. This solution is providing SigFox, GPS, Wifi, NFC, RF and includes an accelerometer.
This is the first minus point but with such capabilities you have some constraints : the size of the module (29mm x 21 mm x 2,3 mm) will limit some of the use cases. But to be honest the solution is quite good for the 95% of other use cases 😉
The module pads are on the bottom of the module only and you will have to be careful when manually placing/soldering the component. For people trained by the Telecom Design Soc it should not be a problem.
The module support up to 5,5V power supply but requires at least 3,2V. It is perfect for a LiPo or NiMh powered solution or eventually for a 3xAA batteries.
The modules own different power load switch you can enable or disable to preserve the energy consumption.
The different included modules are:
- SigFox : OnSemi
- GPS : Ublox-8
- Wifi : ESP8285 or ESP8266
- BLE / MCU : NRf52
- Accelerometer : Bosh BMA250
The main MCU is an NRF52832 – This is a really powerful MCU based on a 32b Arm M4 core operating at 64MHz. It includes 512kb of flash memory and 64kb of RAM.
The first big limit of the module is the number of GPIO, basically you have 2 I2C available and 2 Analog inputs. So basically you need to add an external GPIO extender for you circuit or sensor control. I assume you can remap one of the I2C (debug) ports and the Analog input ports for another usage like GPIO, UART, SPI according to your custom firmware. Globally if you do not use NFC you can get 2 others GPIO. With the reuse of the STATE pin it is a total of 5 possible GPIO.
This post is to be continued…
ESP8285 and UBX-G8020 to be precise 😉
Source : https://github.com/wisol-SFM/WSSFM20Rx_12x/blob/master/development/sigfox_cfg2/source/cfg_board_def.h