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Prime Update Script

A Script for Maintaining Clear QAM Channel Tuning Information Using An HD Homerun Prime


There currently is no fully automatic way to maintain the channel tuning information for a clear QAM tuner. Tools like Scte65scan can help but they do not work 100% of the time because the information needed by such tools either changes from time to time or isn't reported at all by the cable provider.

If you have invested in an HD Homerun Prime (HDHR3-CC or HDHR6-CC) configured with a CableCard, this script will use the channel information automatically provided by your cable provider to your HD Homerun Prime and use it to correct and maintain the channel tuning information of your clear QAM tuner.

Note that your clear QAM tuner does not have to be an HD Homerun for this script to work. This script does not communicate with the clear QAM tuner at all and will correct the tuning information of any clear QAM setup. It will work with any clear QAM tuner.

What This Script Doesn't Do

This script does not perform the initial population of the channel database for a clear QAM tuner. Follow the usual instructions to perform this process.

The wiki has some links to get you started with the classic HD Homerun clear QAM tuner: Hdhomerun

Also see Prime2qam. Note the author of this script has had nothing to do with Prime2qam and makes no representations whatsoever as to its quality or applicability.

How To Configure The Script

Please be sure to read all the comments in the script. The script requires some familiarity with the MythTV database structure. If you misconfigure it it could damage your MythTV setup. Use at your own risk.

Copy the script to an executable location in your system and also make the file executable:

$chmod 755

Configuring the script is simply a matter of editing the collection of variables near the beginning of the script. These are between the comments "Configuration Info" and "Work Begins Here."

Again, please read the comments carefully to see what each variable does. You do not have to configure the email notification function, that is optional. Your system may not be configured for or capable of email.

%prog is a hash containing the full path of two external programs used by the script, mail and hdhomerun_config.

You must download and compile hdhomerun_config from Silicon Dust before using this script. Download it here: Silicon Dust Downloads. This script uses hdhomerun_config to communicate with your Prime and extract the current channel information from it.

$targsourceid is the most important and dangerous variable you can set. This is the Source ID of your clear QAM tuner and will be used by the script when updating channel information. Be sure you set this correctly. If you set it incorrectly, channel information for the wrong tuner will be changed. The videosource table in your database should have a description of each of your sources.

The remaining variables are documented in the script.

Finally, run the script as a cron job. For me Comcast seems to make it's channel changes sometime in the early morning, although I'm not sure exactly when. Since I very rarely make recordings in the morning, I run this script twice, at 3:00 AM and 9:00 AM.

To Do

It's been rightly pointed out that I am not using the perl bindings used by the other perl scripts that are part of MythTV. Using the bindings would avoid the need to manually find and connect to the database. There is also an interface to do things like add new entries into dtv_multiplex.

The Script


# (C) Copyright 2011 Kirk Bocek
# t004 (at) - Comments & Feedback Welcome
# Update the MythTV virtual -> physical channel maps of a Clear QAM
# recorder using the built-in virtual channel tuning of an HD Homerun 
# Prime HDHR3-CC or HDHR6-CC.
# AND THE MYTHTV DATABASE STRUCTURE. This script directly manipulates
# MythTV tables. This behavior is strongly discouraged by the MythTV 
# devs and this script is neither endorsed nor vetted by them. Use at
# your own risk.
# With that caveat in place, I am fairly confident that the manipulations
# of this script are mild. I touch only two tables: 'channel', to re-tune
# only *existing* channels, and 'dtv_multiplex', to insert missing
# frequencies if necessary.
# Tune a virtual channel on a Prime, extract the physical channel and
# program number. Check and update Clear QAM channel mappings with 
# this information. Note that this only works if your Clear QAM source
# is using the *same* virtual channel numbers as your Prime.
# This only uses tuner 2 on your Prime as this tends to be the last
# tuner that Myth uses. It will check if the tuner is in use and
# will fail after a timeout period if the tuner remains in use.
# 20111015 - First version.
# 20111017 - Fixed comments mentioning Classic HDHRs. Added more
# 	error messages. Added $writeswitch. Changed getting 
# 	program number from /tuner2/streaminfo to /tuner2/program
# 	Removed one of the sleep commands
# 	Fixed dtv_multiplex search
# 20111019 - Added code to insert missing dtv_multiplex records.
# 	Stregthened warnings in comments.
# 20111024 - Fixed comments. Changed default config.
# Thank you Bill Lash & his cat Ozzy for their help in getting this
# script up and running.
use strict;
use DBI;

# Configuration Info, customize this for your setup:
# $primeid is the network id of your HDHR3-CC or HDHR6-CC.
# !IMPORTANT! $targsourceid must be set correctly! Otherwise the
# wrong channels will be changed.
# $targsourceid is the sourceid in the channels table that will be
# updated with the information extracted from the HDHR-CC. This should
# be the source being used by your Clear QAM tuner. If you're not sure
# what this number should be, take a look at the videosource table 
# for the description of each of your sources.
# @chans is the list of channels to be checked on the Prime and updated 
# in the source used by your Clear QAM tuner.
# $email is an email address to receive update messages. An email is sent
# only if something is changed or $debug is set. Make sure email is 
# properly configured on your system. Leave this blank to disable.
# $timeout is the number of times the script will check tuner2 for 
# availablity before failing. 1 second delay between tries.
# %prog is the full paths of external programs used by this script.
# $debug - display and email non-error messages. Normally, set this to 0.
# $writeswitch - If set to 0, nothing will be written to the database.
my $primeid = '12345678';
my $targsourceid = 99; #!!Set This Correctly
my @chans = qw/ 9 10 702 703 704 705 706 707 709 711 712 713 714 715 716 717 722 /;
my $email = '';
my $timeout = 10;
my %prog = (
	'hrconfig' => '/full/path/to/your/hdhomerun_config',
	'mail' => '/bin/mail',
my $debug = 0;
my $writeswitch = 1;

#Database Setup
my $dbserver = "Database Server Hostname";
my $database = "mythconverg";
my $user = "username";
my $pwd = "password";

# Work Begins Here
my $mailtext = undef;
my $model = `$prog{hrconfig} $primeid get /sys/hwmodel`;
chomp $model;
die "Device is not an HDHR Prime\n"
	unless $model eq 'HDHR3-CC' or $model eq 'HDHR6-CC';

# Connect to the database.
my $dbh = DBI->connect("DBI:mysql:database=$database;host=$dbserver",
    $user,$pwd,{'RaiseError' => 1})
    or die "Cannot connect: " . $DBI::errstr;

# Main Loop - Do each of the channels
MAIN: while (@chans) {
	my $curchan = shift @chans;
	my $loctime = $timeout;
	my $status = undef;
	STATUS: while ($loctime) {
		$status = `$prog{hrconfig} $primeid get /tuner2/status`;
		last STATUS if $status =~  /ch=none/;
		sleep 1;
	unless ($status =~ /ch=none/) {
		$mailtext .= "PrimeUpdate script failed.\n";
		$mailtext .= "Tuner 2 is busy: timed out on channel $curchan.\n";
		last MAIN;

	`$prog{hrconfig} $primeid set /tuner2/vchannel $curchan`;
	sleep 1;
	my $progid = undef;
	my $chaninfo = undef;
	$progid = `$prog{hrconfig} $primeid get /tuner2/program`;
	$chaninfo = `$prog{hrconfig} $primeid get /tuner2/channel`;
	`$prog{hrconfig} $primeid set /tuner2/vchannel 0`;
	chomp $progid;
	chomp $chaninfo;
	unless ($progid and $chaninfo) {
		$mailtext .= "Error tuning channel $curchan on device $primeid\n";
		$mailtext .= "Frequency and program number were not returned.\n";
		last MAIN;

	print "Channel $curchan\n";
	$mailtext .= "\nChannel $curchan:\n" if $debug;

	my ($tmp,$freq) = split(':',$chaninfo);
	#Get dtv_multiplex record for frequency
	my $mplexid = undef;
	$mplexid = $dbh->selectrow_array(
			"SELECT mplexid from dtv_multiplex 
			WHERE frequency = $freq and sourceid = $targsourceid;");
	unless ($mplexid) {
		# If $mplexid comes back empty, this frequency is missing from
		# dtv_multiplex. Add new frequency.
		# See
		my $res = "Database update not performed.\n";
		$res = $dbh->do("INSERT INTO dtv_multiplex SET
			sourceid = $targsourceid,
			frequency = $freq,
			modulation = 'qam_256',
			sistandard = 'atsc';") if $writeswitch;
		$mplexid = $dbh->selectrow_array("SELECT last_insert_id();");
		unless ($res and $mplexid) {
			$mailtext .= "Inserting new frequency $freq for source $targsourceid failed.\n";
			$mailtext .= "DBI::errstr = " . $DBI::errstr . "\n";
			last MAIN;
		$mailtext .= "Added new mplexid $mplexid for $freq into dtv_multiplex table.\n";
		$mailtext .= "DB Insert returned: $res\n";
	$mailtext .= "From Prime: Freq is $freq, Program ID is $progid\n" if $debug;
	$mailtext .= "From dtv_multiplex: mplexid for $freq is $mplexid\n" if $debug;

	#Get current channel setting in target sourceid
	my ($dbmplex,$dbprog) = (undef,undef);
	($dbmplex,$dbprog) = $dbh->selectrow_array(
		"SELECT mplexid, serviceid from channel where
		sourceid = $targsourceid and
		channum = $curchan;");
	unless ($dbmplex and $dbprog) {
		$mailtext .= "Channel $curchan was not found in channel database for \n";
		$mailtext .= "sourceid $targsourceid. Make sure your Prime and Clear QAM\n";
		$mailtext .= "channels are the same.\n";
		last MAIN;
	$mailtext .= "From channel db: Source $targsourceid, " .
		"mplexid is $dbmplex ProgID is $dbprog\n" if $debug;

	if ($progid != $dbprog or $mplexid != $dbmplex ) {
		#Channel has moved, update channel database
		my $res = "Update Not Executed.\n";
		$res = $dbh->do(
			"UPDATE channel 
				set mplexid = $mplexid, serviceid = $progid
				channum = $curchan and sourceid = $targsourceid;"
			) if $writeswitch;
		$mailtext .= 
			"Channel $curchan updated to mplexid $mplexid, service $progid\n";
		$mailtext .= "DB Update returned: $res\n";

print $mailtext;

# Send Email
if ($email and $mailtext) {
	open FH,"|$prog{mail} -s PrimeUpdateScript $email";
	print FH $mailtext;
	close FH;