This post was last edited by Beifang on 2021-12-20 15:29
1. Connect and test
After unpacking, the information I got is still incomplete. I am not very clear about the use of the board. I need to test it. However, the main work is the serial port AT command control and feedback, so I need to test the serial ports one by one. Therefore, I tested USB and serial port 1 and serial port 2.
2. Connect USB and power on
After connecting to USB, the LED light only flashes twice. The serial port CH340 can be opened, but there is no data or information exchange.
This is different from what is shown in the manual, which should be due to the change in version number.
3. Connect serial port 0, TX0, RX0
This can only display the sent information, not the returned information.
4. Connect serial port 1, TX1, RX1
This time the displayed data is restored, but the displayed content is garbled. If AT+CGSN is entered, it will be displayed as continuous FF.
This is a function requirement of the built-in firmware.
5. Testing Flashtools
The firmware upgrade uses flashtools. This action may cause the device to become bricked, so test the interface first and then test it after you understand it clearly.
Serial port initialization successful.
Select the compiled binary file,
Select download to download through the serial port, and the hardware test is passed.
This work can be completed later.
6. Connection method
The reference connection method is as shown below.