Gurux.Serial.Android 3.0.6 – CH340 (HL-340) USB-Serial Adapter Not Working,

Hi Mikko, thanks for your quick response.

I am using the same GXSerial configuration as in GXDLMSDirector.
My code works fine with CP21X and FDI optical cables, but with the CH34X optical cable the port is detected and opened successfully, yet no communication occurs between the meter and the app.

Verification steps:

The CH34X cable works with Gurux Serial Java sample on Windows.

The same cable also works with the Serial USB Terminal app on Android.

Given this, are there additional configuration settings (e.g., flow control, DTR/RTS, baud rate adjustments) required for CH34X on Android with GXSerial?
Or can you share any other details that might help resolve this communication issue?

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val media = GXSerial(context)

val ports = media.getPorts()
Log.d("USB_DEBUG", "Ports count=${ports.size}")

if (ports.isEmpty()) {
Log.e("USB_DEBUG", "No USB serial ports found")
return false
}

for ((index, port) in ports.withIndex()) {
Log.d("USB_DEBUG", "Port[$index]=$port chipset=${port.chipset}")
}

val port = ports[0]
media.port = port
media.baudRate = BaudRate.BAUD_RATE_9600
media.dataBits = 8
media.parity = Parity.NONE
media.stopBits = StopBits.ONE

Log.d("USB_DEBUG", "Opening ${port} chipset=${port.chipset}")

// Store it before opening.
mDevice.media = media

media.open()
Log.d("USB_DEBUG", "GXSerial opened: isOpen=${media.isOpen}")

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If you want to anything from me, reply me

Hi Kurumi,

Thank you for your quick response.

As you suggested, I had already tried enabling DTR and RTS using the following:

media.setDtrEnable(true);
media.setRtsEnable(true);

However, I am still facing the same issue.

Could you please suggest what else I can check or try?

Thank you kurumi for great support, now it is working