Difference between revisions of "Scte65scan"

Revision as of 04:18, 25 May 2009

Overview

Comcast is transitioning away from analog to digital. For those customers not upgrading to digital TV's, they are providing free digital to analog converters (DTA's). Traditionally, their full featured set top boxes (STB's) received all sorts of information such as encryption keys, guide data, etc via an out of band (OOB) POD interface. This is a special receiver that tunes frequencies outside of the normal TV frequencies. One of the pieces of information that's transmitted is a table that maps station callsigns and virtual channels (the integer channels that the STB's present to the user and are used by TV Guide, Schedules Direct, zap2it, etc) to RFchannel.program number that clearQAM TV's use. For example, Schedules Direct and Comcast may say FOODTV is channel 35 but a clearQAM capable TV plugged directly into the line will report it as 78.4. This would also traditionally require one to use the MythTV channel editor and manually input the frequency and program number for each channel and associate the xmltvid. Since Comcast is handing out DTA's for free, they are severely cost reduced and don't have a POD interface. In it's stead, they are transmitting the virtual channel table in-band (i.e. tuneable with a conventional clearQAM tuner) to allow the DTA's to do the virtual channel mapping.

The scte65scan tool

scte65scan is a utility that will read the in-band virtual channel tables and automate the mapping of frequencies and program numbers to virtual channels and xmltvids.

A quick overview of the process is as follows:

• Find the VCT_ID for your lineup. This can be done by obtaining a DTA or STB and reading it from the diagnostic page. Alternatively, it can also sometimes be found by inspection through an examination of the text-mode output of scte65scan
• Generate SQL for importing into MythTV (e.g. 'scte65scan -f3 -V your_VCT_ID itfile > vct.sql')
• Import the SQL into MythTV (e.g. 'mysql mythconverg < vct.sql')

The next time it is run, mythfilldatabase will detect the virtual channel number in the 'freqid' and/or 'channum' field of the imported SQL and fill in the xmltvid for you if you are using Schedules Direct. Be sure to enable the channels at Schedules Direct prior to running mythfilldatabase.

For more information, visit the scte65scan project page

How to determine VCT_ID using a Full Set Top Box

For those without DTAs, it is still possible to determine the VCT_ID using most set top boxes. This method is tested on Motorola DCH-3200s and DCH-6200s, but should work for other Motorola models as well.

1. Power on your box.
2. Press "Power" on the remote to turn off the box. IMMEDIATELY press "OK" on the remote. You should see a long list of menus numbered d01-d18.
3. Select option d6, "Current Channel Status."
4. You should see VCT ID listed on this page. It may only be one or two digits, which should correspond to the last one or two digits in the VCT_ID. You can run the scte65scan tool with no options to see the available tables. If the VCT_ID on your set top box is "10" and the scte65scan program shows that one of the VCTs is 3010, then this is your VCT_ID. Take note of both the numerical and hex VCT_ID and enter them in the table below.

VCT_ID by Location

Please post your Zip code, city, and VCT_ID in the table below to allow others without DTAs to determine a probable/possible VCT_ID choice.