[mythtv-users] Configuring USB->serial converter to control DirecTV set top box

djg at pdp8.net djg at pdp8.net
Sun Dec 3 21:20:51 UTC 2006

> I was able to get this to build with your patch, but I'm still getting
>timeout errors. dmesg reports:
>usbcore: registered new driver usbserial
>drivers/usb/serial/usb-serial.c: Had to override the open usb serial
>operation with the generic one.
Getting a little past my knowledge but it looks like the 7703 and standard
drivers are not getting along.  I'm sure their is another list with
more expertise in this area but not sure what it is.

Look in /proc/bus/usb/devices or use command lsusb
for your serial adapter vendor and product id.
Verify that matches the ids in mos7703.h to make sure it knows this
is the correct driver.

It should have also created a line with those ids in

If nothing obvious shows up its probably easier to buy a supported device
unless you are finding this interesting.

Also I did see one posting that stated that some of these USB serial
devices have rx and tx swapped (null modem setup).  If you happend to
have one of the rs-232 light boxes or a DVM thats easy to check.

If you can short pin 2 to 3 that will loopback the data.  If my script then
no longer gives timeouts but displays received data the device
is working and probably has the opposite pinout.  If you try this try with
original and 7703 driver.

I take it your box doesn't respond to the commands being sent?  If the USB
device wasn't receiving data but was still sending the box would execute
the command.

More information about the mythtv-users mailing list