I've been testing a Chinese usb-serial cable, like this one, with no success. It just gives me garbage. So first of all, yes I installed correctly the ch340 driver for the cable. For my test, I configured the Atmega328p to keep sending numbers at 9600 baudrate. It works fine when using the atmega328 through the arduino uno platform; the numbers are correctly received and shown in the serial monitor. But when I used the chinese usb-serial cable, all I got in the serial monitor is sequences of garbage. I also tried receiving the data through the arduino uno and the serial cable at the same time (connecting the cable to the Tx pin of the arduino uno); and again, the data received through the arduino uno is ok, but the data received from the usb cable is garbage. Did you get this error before? Have you managed to solve the problem? thank you.
What makes you think that it needs the CH340 driver?
I see no mention of it on the webpage.
Windows 7, 8 and 10 do not require the CD windows update can get the newest and lastest driver.
Because this serial cable is based in the ch340g chip, which is not officially supported. So driver is needed.
The posted site shows a RS-232 interface cable, are you using RS-232 signals?
paolocd: Because this serial cable is based in the ch340g chip, which is not officially supported. So driver is needed.
That makes no sense.
The datasheet says no driver is needed.
larryd: The posted site shows a RS-232 interface cable, are you using RS-232 signals?
Wouldn't be surprised that he is clueless and linked to the wrong cable.
I used the link because I just wanted to show how the cable looks like. As I said the one I got is chinesse, looks exactly the same as the cable in the picture, and it has no datasheet or manual (I haven't been able to find one). It does need the driver.
Btw I managed to make it work. The cable uses 0V and 5V, but it uses inverse logic for transmitting and receiving data. So I used an inverter to set it up for the arduino serial communication. :)