Re: RS232-to-USB adapter with dial-up modem
On Friday 17 September 2010 15:52:34 S D wrote:
> > From: Phil Requirements <firstname.lastname@example.org>
> > What are you using to try to dial out?
> I'm using pppd and the respective pon/poff scripts and configuration files.
> This configuration works fine with the modem when the modem is connected
> via a RS-232 port. When the modem is connected via a USB port it doesn't.
> The only change in the configuration appears to be the device (/dev/ttyS0
> vs /dev/ttyUSB0) to which the modem is attached to.
> > Perhaps a silly question, but does the adapter require that you install a
> > driver?
> There's a CD that came with the cable but it only contains stuff for
> Windows. The vendor did not explicitly claim it'll work with GNU/Linux.
> Linux does seem to recognize the modem, in the log it says "usb 1-9:
> ch341-uart converter now attached to ttyUSB0", so it looks like the problem
> isn't with the missing driver(s).
> I'm beginning to think John Hasler was right when he said that "they've
> failed to implement enough of the modem control lines and/or gotten the
> voltages wrong" and suggested to throw the cable away and buy a new one.
> That would be a pity though.
I used to use a keyspan usb>rs232 adapter. It used a kernel module, which you
would see if you ran 'lsmod'. That said, it was recognised and module loaded
automagically. Which could support the 'throw it away' scenario.