The DCT 2000 User Guide (General Instrument)

Note: your current digital cable boxes are from Motorola*, but are identical in all respects (except General Instrument XRC 100 remote; see page 5).

Note: The Motorola boxes do not have component or s-video output ports:
only composite (yellow) output. Also an "Auxiliary Audio In" port (red and yellow) for stereo audio loop-though
(e.g. attach CD player out to Aux Audio In on cable box, then Audio out from cable box to Aux In on Stereo Receiver).

*i.e. these are Motorla DCT-2000s

The DCT 2000 & TiVo:
"You can use the Serial Control cable for channel changing if
you have a Motorola/General Instruments DCT2000 series cable box, and your cable
provider has enabled it for serial control." (If not, you can use the IR Control Cable.)

For this to work:

• You must have a Motorola or General Instruments DCT2000 series cable box (including the DCT2224 or DCT2244 models).
  --This is the only model of cable box that is currently supported with serial control. Often the model number can be found printed on a label on the bottom of the cable box.
• The cable box must be running firmware version 7.54 or later.

--What Cable Boxes are Compatible with TiVo?
Richard says all known cable boxes are controllable by TiVo. When there is a new cable box without existing IR codes, they borrow a remote, suck the codes out of it, and add support for it via an update.

In spite of the serial cable included with many TiVos, there is only serial support for Series 2 AT&Tivo users who have a DCT-2000 cable box. Also the cable box must have the correct software.

Here's a note from TiVo about Motorola cable boxes: "Motorola recently bought General Instruments and relabeled all of their units from GI to Motorola. The GI/General Instruments codes works on these units. We are working on adding Motorola to the list of codes but I haven't been able to verify when thiswill occur yet."
-- Michael G Caine, TiVo Customer Care

Some GI boxes were actually made by Clearview. Thus, you may find the IR codes you need to control your GI box under the Clearview selections. For example, some have found Clearview code 10019 to work for a DCT-2244, or Clearview 10021 for a GI 1134. The DCT 2000 may also need a Clearview code.

Personal experience: Installed a Hauppauge PVR-150. Comes with an IR Blaster and a little set-up program [BlastCfg.exe]. I taped the IR Blaster end right over the IR receiver in the cable box.
The code for my Motorola Cable Box (Comcast cable San Jose, CA) turned out to be General Instruments Code Set: 0029.