We are facing a strange behavior on a WIZ105SR module when transmitting data on the serial port.
We succeed when connecting the WIZ105SR to the PC and transmitting data using a virtual COM on the PC. However, when the MCU in our target board responds, we observe that the voltage at pin 3 of J1 (RXD) is always high (3.3V):
Seems like the RXD pin on the GC89L591A0-LQ44I of the WIZ105SR is set as an output and keeps always high level.
Could you please support us on this and check what we are doing wrong on the device?
Thanks in advance.