test_ttx.readme

IBM source for pallas/vulcan/vesta

TEST_TTX Teletext Application README File
-----------------------------------------

Purpose:     The purpose of this readme is to describe how to use the
             "test_ttx" application.

Preliminary: Before using the "test_ttx" application, ensure that the
             Teletext node has been created and the module has been
             installed.  Refer to the readme file in the "STB04xxx"
             directory for details.

Invokation:  Type "test_ttx" and then enter on the Linux command line to
             display the Teletext command prompt.

Menu
Options:     Below is a description of the menu commands supported:
               1. t h[elp]            - Displays the command menu.
               2. t init              - Initializes the Teletext Driver. Open
                                        required drivers and allocate resources.
                                        This step is required before the
                                        teletext display can be started.
               3. t term              - Terminate the Teletext Driver. Close
                                        all drivers and release all resources.
               4. t start <ppid tpid> - Start teletext display where:
                                         ppid = the PCR PID
                                         tpid = Teletext PID
                                        Teletext driver must be initialized.
               5. t stop              - Stop teletext processing
               6. t stat <get|clear>  - Get:   Get Teletext processing stats.
                                        Clear: Clear Teletext processing stats.
               7. t q[quit]           - Close the Teletext Driver (ie. "t term"
                                        is implicitly performed) and return to
                                        the Linux command prompt.

Application
Notes:       1. Teletext is supported in PAL mode only.
             2. During initialization of the Teletext driver, an attempt
                will be made to open the Video Driver to change the video
                format to PAL mode.  In the event that the video driver is
                already opened (ie. by the "test_av" application), the open
                will fail since the video driver can only be opened by one
                application.  In this case, "test_ttx" assumes that the
                display format has already been set to the PAL format.  If
                it has not, the Teletext driver initialization step will fail.