Widora AIR V4.0 Error USB

Hi.

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.

Please, can you give us a solution, it is urgent.

Thanks

@emilts What happened to the test?

@emilts OK

We will try to modify the programming and if we do not succeed we will look for and buy another ESP32.

@emilts
Is the communication correct under the test?
If it is correct on the computer, it should be the same on the mobile phone

One of the apps we use indicates:

Serial Device CP210x

Vendor: ID: 10C4 Name Silicon Labs

Prpduct: ID: EA60 Name CP210x

I do n’t have an Android device here. You can see how to identify the CP2104 on the Android device. Maybe he should appear on /dev/ttyUSB?

@emilts said in Widora AIR V4.0 Error USB:

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?
https://www.silabs.com/products/interface/usb-bridges/classic-usb-bridges/device.cp2104?q=cp2104;page=1;x6=searchHeader;q6=Software

@kevin said in Widora AIR V4.0 Error USB:

boot

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.

@emilts you means AIR4.0 with the USB_OTG cable, AIR4.0 not boot? or AIR4.0’s bluetooth not work?

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.

https://github.com/jalucenyo/USB-Arduino-Android/tree/master/TestUSB2Arduino

http://android-er.blogspot.com/2014/09/bi-directional-communication-between.html

@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.