User`s manual

Page 32 of 83
8-2-3 Channel Change
There are three ways to select a channel in the reference TV application: channel up/down, digital, and last
buttons in remote controller.
• Pressing the channel up or down key tunes to the next highest or lowest channel in the selected channel
map; a channel in a different channel group (analog or digital) is tuned at the limits of the available scan.
The channel map is established through the Auto Program menu, which automatically removes any no
signal channels. After channel scanning, the channels are grouped as digital channels and analog
channels.
• For digital channels, the channels are sorted on the virtual channel number. Further manual editing of the
channel list can be done through the Manual Channel Set menu. If no channels are enabled in the
selected channel map after initial power on, then the channel up/down keys select the channel number
next to the current channel, and determine the analog or digital channel based on the availability of
signal.
• Channels can be directly accessed by pressing the digit keys on the remote controller. The channel
selected is tuned immediately if the OK key is pressed, or will be tuned automatically after two seconds
of inactivity following the last entered digit. If the entered digit keys starts with a zero (“0”), the channel
number will be tuned to the second digit (for instance, the digits 03, entered in sequence, will tune
immediately to channel 3). Any channel may be selected by this method, regardless of its presence or
absence in the current channel map.
• Pressing the Last key in the remote control tunes the channel selected prior to the currently tuned
channel. For ATSC channels, it selects the sub-program number as well as the channel number.
The above channel-change operations are implemented via the Tuner and Channel Map APIs.
After tuning, the application displays the information of the currently-tuned channel. This includes:
1. Channel number [Ch 9-1]
2. Channel Label [for instance, KQED]
3. Current Time [for instance, 12:30 PM]
4. Rating information [for instance, TV-PG]
The virtual channel number will be displayed if the current channel is digital. The channel label is extracted
from input signal if there is no label setting for the current channel. The channel label can be explicitly set with
Channel Labels menu, which will use TLChMapSetChannelName to store the label.
8-2-4 Volume and Mute Control
Pressing the volume Up or Down button changes the current volume in the Control Array and applies this
change to the hardware block. The range of control is determined by the Control Array; the current
implementation has a range from 0 to 63. Pressing either of the volume keys clears the mute audio mode of
operation, if previously set. If no button is pressed for five seconds after pressing the last volume Up or Down
button, the volume display will be automatically removed.
The reference application supports audio mute or unmute by pressing the Mute key. When mute is enabled,
the audio is muted, displaying an icon on upper right side. The mute condition is cleared when the TV is
powered off.
Pressing the Mute key invokes the mute icon on the right corner of screen.
8-2-5 Closed Caption Selection
This section describes how to enable Closed Caption (CC) on the Phobos TV application. When the TV
is switched ON, captions are disabled by default. The user switches captions ON using the [SUBTITLE] key
on, a new language/CC option is displayed near the bottom center of the display. The sequence of options
available are listed below (depending upon the stream type- ATSC/NTSC).
For ATSC, English – Spanish – French –Portuguese-Off
For NTSC, CC1 – CC2 – CC3 – CC4 – Off The displayed CC option can be set either, it is set automatically
after two seconds.