A worldwide television tuning system is configurable to the television standards
and channel frequencies of multiple different countries based on a country's ITU
long-distance country code. The tuning system maintains a country code table listing
a plurality of countries according to their ITU codes. The tuning system also maintains
multiple channel-to-frequency mapping tables that correlate channel numbers to
corresponding frequencies for associated countries in the country table. The country
table indexes the channel-to-frequency mapping tables. During configuration, a
user or application selects a particular country by passing in the ITU code. The
tuning system uses the ITU code to locate an entry for that country in the country
code table. The table entry contains an index to an associated channel-to-frequency
mapping table for the selected country. The tuning system loads and saves the channel-to-frequency
mapping table for subsequent use. The channel-to-frequency table also identifies
the appropriate television standard for the selected country. During tuning, the
user or application enters a particular channel number. The tuning system uses
the channel number to lookup a corresponding television frequency in the channel-to-frequency
table. The tuning system then tunes to the television frequency. The tuning system
stores a set of tuning frequencies for corresponding channels within a particular
locale. If the tuning system is transported to another locale and then back to
the original locale, the tuning frequencies may be retrieved from memory to restore
operation within the original locale, rather than having to reconfigure the system.