# Driver for CH341 USB/RS232 adapter



## balanga (Mar 8, 2018)

Do I need a driver to enable usage of a CH341 USB/RS232 adapter?

`lsusb` tells me the VID/PID is 1a86:7523 - an HL-340 USB-Serial adapter.


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## tobik@ (Mar 8, 2018)

You need uchcom(4), but it should be loaded automatically when you plug it in.


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## balanga (Mar 8, 2018)

I do see the msg

```
uchom0 on uhub1
```
when the adapter is inserted so I guess support for it is there, so in theory it should work, but how do I actually test it?

I thought I'd dig out my old USR Courier HST modem to see if any lights on it could be flashed using minicom....but it has some strange power connector which I couldn't find. Maybe I'll try using my old LapLink cable if I can find it...

How else can I see if it's actually working?


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## sko (Mar 12, 2018)

balanga said:


> How else can I see if it's actually working?



You can do a serial loopback test by connecting the RXD and TXD pins of the RS232 connector (IIRC pin 2 and 3, but please double-check beforehand).
If you then connect to the serial port (usually /dev/ttyU0) with e.g. cu(1) (or minicom, screen, ...) you should be able to see everything you type as it is sent and immediately received.


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