I have a question about RTL8710 which is similar to ESP8266. If I want to use it on Arduino or Raspberry, I need to connect it to WIFI when the Arduino or Raspberry starts, right? Or can I configure it offline and then connect to Raspberry
Both micro controllers do have the typical init() and loop() functions. Hence, once you power them up, you need to make the ESP initialise the WIFI and then listen for commands or keywords on the serial interface. Means, you can program both offline, power them up, connect the serial port. Be aware, that the ESP can do most of what the typical Arduino can, too, maybe even faster.
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