Help - Search - Members - Calendar
Full Version: Multiple pl2303 serial adapters
Linuxhelp > Support > Hardware Support
After the required many hours of googling, I've run out of things to google on..

I picked up a few cheap USB Serial adapters from eBay (based on the PL2303 chipset, HX I beleive). But work find under windows and both are detected with my 2.6.16 kernel, dmesg shows:

usbcore: registered new driver usbserial
drivers/usb/serial/usb-serial.c: USB Serial support registered for generic
usbcore: registered new driver usbserial_generic
drivers/usb/serial/usb-serial.c: USB Serial Driver core
drivers/usb/serial/usb-serial.c: USB Serial support registered for pl2303
pl2303 1-2:1.0: pl2303 converter detected
usb 1-2: pl2303 converter now attached to ttyUSB0
pl2303 2-2:1.0: pl2303 converter detected
usb 2-2: pl2303 converter now attached to ttyUSB1
usbcore: registered new driver pl2303
drivers/usb/serial/pl2303.c: Prolific PL2303 USB to serial adaptor driver

The problem is only one of the two seem to work once connected, sometimes it's ttyUSB0 other times it's USB1 (I haven't yet found a pattern for it, but the only way to make the other work is a reboot). If both are unplugged during boot, the first plugged in will ALWAYS works and the second never will.

HELP!? Thoughts?

Hi Bill,

I know what you mean - i'm in the same boat. in fact that's how i found your post after googling for too long onit.

It sounds like you have the HX chipset of the pl2303 - you can confirm with a lsusb -v -d 0x067b:0x2303
and look for the 'bMaxPacketSize0' entry - if it's 64 then you have the HX version.

It looks like the code for the HX version doesn't work for this adapter though - even in 2.6.16 (and even though it's detected by the kernel).

Would you be able to paste your 'lsusb -v -d 0x067:0x2303' output in please?

This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2018 Invision Power Services, Inc.