Troubleshooting
1. How to enter download mode?
First press and hold the Volume- button, then lightly press the reset button, and finally release the Volume- button to enter the download mode.
2. SA868 power problem
The SA868 module supports low (1.6W) / high (1.8W) power; the power can be selected by controlling the level of Pin#7 of SA868. The program uses low power by default, if you choose high power, it will cause the temperature of T-TWR to be too high, please use it with caution.
Warning
When there is no program in esp32s3, Pin#39 of esp32s3 is floating, and the power of SA868 will be set to high power.