We have a big problem. We are carrying out a project based on the ESP32 Widora-AIR V4.0 microcontroller, since it has a small size and we have housed it in a 20mm cylinder. In the end we bought about 20 to perform tests and prototypes and we are basing the whole design on it.
We have performed the tests first with other ESP32-WROOM-32 microcontrollers, which are larger and everything has been working correctly with a bluetooth connection between the microcontroller and Android devices. With Widora everything has also worked perfectly.
We have found the problem when we have changed the bluetooth connection by usb otg connection, between the microcontroller and the Android device, since we need our clients to establish both types of communications alternately, because while with other microcontrollers the bi-directional data exchange works correctly, with Widora we don’t get the data to be transmitted.
Widora starts and works perfectly by connecting the USB OTG cable, and in this way the data transmission also works with Bluetooth.
What does not work is the transmission of data via the USB connection.
oh, usb-ttl bridge is CP2104 ? can your android identify it?
Widora starts and works perfectly by connecting the USB OTG cable, and in this way the data transmission also works with Bluetooth.
What does not work is the transmission of data via the USB connection.
I don’t use any pin. I simply connect, using a USB OTG cable, the ESP32 with an Android phone or tablet and try to send and transmit simple data, but with Widora it does not work, I have used the following examples and with other ESP32 the transmission is correct.
@emilts OK,
Don’t you understand that, can you draw a simple block diagram?
check if you used GPIO21 pins, V4.0, this pin may affect the reference frequency of the crystal, which may cause radio frequency anomalies.