[SGVLUG] USB/RS232 adapters

[Michael Proctor-Smith]

On 10/11/07, Claude Felizardo <cafelizardo at gmail.com> wrote:
> Has anyone had any luck with USB to RS232 adapters?
>
> I've been trying to get at least one of the x10 controllers to work on
> my laptop but haven't had any luck.  My laptop doesn't have any RS232
> ports so I first tried a CM15A which is USB and I know works on my
> winXP box.  Unfortunately, X-10 never released the specs so it looks
> like everyone gave up when Smarthome came out with their Insteon line
> and provided more help.  The last set of drivers I could find were
> dated 12/2004 and supported Linux 2.4 and possibly 2.6 but when I
> tried it with my 2.6.17 kernel I got warnings and errors which I tried
> to resolve but I couldn't get it to work. Either that or the sample
> app is broken.
>
> So then I tried a USB/RS232 cable I had lying around.  The system
> recognizes it as an HID->COM RS232 Adapter and loads the cypress
> driver which creates the /dev/ttyUSB0 device.  Using the latest 2.x
> version of heyu (and x10 app for Linux), I get timeouts and errors
> when I try it access either the CM11A or CM17A X10 controllers.   If I
> try this on my fileserver which actually has a VScom 400H 4 port
> serial adapter using /dev/ttyS2 it works fine.  Fails when I try USB.
>
> Now I did get this USB/RS232 adapter several years ago so it's
> possible its broken.  I'm pretty sure it was working with a windoze
> GPS app but it's been a while plus I may never have gotten around to
> trying it via Linux as I had gotten a new GPS receiver that has a USB
> port.
>
> So, can anyone recommend a USB/RS232 adapter that they have used with
> Linux?  If possible, can they bring it to tonight's meeting so I can
> verify it works with x10?  Then I can try and pick one up in time for
> my demo next month?  I really don't want to have to lug my fileserver
> into the meeting as well as the other gear.

I have found I wanted to use usb/rs232 adapter to talk to a OBDII
interface that most usb/serial adaptors drivers to not implement a
full serial port only a subset. I can bring one to try but I think the
problem is the kernel drivers for alot of hardware is reworked copies
of the same driver that does not implement the whole driver.

> claude
>