Silicon Radar SiRad Easy, Manual, Page: 11 / 14

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Evaluation Kit SiRad Easy® r4, SiRad Easy® & SiRad Simple®
User Guide Version 2.5 19-Nov-2021
4.1.2 Wireless Data Connection
The WiFi interface pins of the sensor board are shown in Figure 15 (left). To run the sensor in WiFi mode, use the
three jumpers delivered with the sensor and close the power jumper (J2) for the WiFi module (switched on) and
connect two jumpers between MT/WR and MR/WT on the external header (J1). Apply +5V to the 5V pin and GND
to the any GD pin (there are four).
Figure 15 WiFi pinout on J1 (left) and WiFi mode configuration (right)
4.2 Firmware Update
Please also see the
Firmware Update Wiki page for detailed information about firmware updates and the
Download Area to download the stm32flash tool for flashing the firmware or esptool for updating the WiFi
firmware.
4.2.1 Microcontroller
To update or change the microcontroller firmware, the board has to be set in bootloader mode, as shown in
Figure 16. This is done by switching the DIP switch MP to the ON position. Then connect the module to the PC via
a Serial/USB (FTDI) cable or Serial/USB adapter using the external header (J1). Please read Section 4.1 about the
external header connection. Connect line TX to MR (microcontroller RX) and line RX to MT (microcontroller TX).
Make sure to use a cable with 3.3V TTL levels!
Download the stm32flash tool. Copy the desired firmware into a folder together with the stm32flash tool. Edit the
batch file stm32flash.bat and replace the COM port with the COM port of your Serial/USB (FTDI) cable or
Serial/USB adapter and the firmware name with the desired firmware, for example:
stm32flash.exe -b 115200 -w <date>_SiRad_Simple_L8_<version>.bin -v -g 0x0 COMx
The baud rate for flashing the firmware needs to be 115200 baud. Run the batch file and the microcontroller gets
programmed. After about 30 seconds the programming is finished. Switch the DIP switch MP back to the OFF
position and do a power cycle to reset the module.
4.2.2 WiFi Module
Connect the sensor using a Serial/USB (FTDI) cable or Serial/USB adapter as shown in Figure 17 using the external
header (J1). Please read Section 4.1 about the external header connection. Switch the DIP switch WP to the ON
position. Then connect cable TX to WR (WiFi RX) and cable RX to WT (WiFi TX).
Make sure to use a cable with 3.3V TTL levels!