AT commands through Microcontroller

Dear WiFi enthosiasts,

I am trying to establish a serial port connection between an mbed LPC11U24 board and the WizFi220 Evaluation Board. I have connected the tx and rx pins of the microcontroller to the rx and tx pins of the WizFi, and I attempt to send the basic ‘AT’ command at a baudrate of 115200. The writing seems to be accepted by the microcontroller, but when I use the mbed’s native readable() function (which checks whether there is something to read at the UART).
The function doesn’t show the WizFi as readable, no matter what I do.

Are there any basic settings or oft-made mistakes that I possibly have done? Is there any workable non-Arduino microcontroller code using the UART (or another means of communication) findable on the web?

Best regards,

An electronics newbie


  1. Please check the led blink when power is up.
  2. Re-write the firmware because uart firmware and spi firmware exists Independently.
  3. please check correct connection, default uart is UART0(J9)
  4. check the 2 switchs, move to [RUN], move to [CMD] on the Evaluation board.