Visual Circuits H-DVP, User Manual

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Troubleshooting
43
Q. All my files are set up correctly for cross-channel
synchronization, but they are still not synchronizing. Why?
A. Two settings in the Windows NT Registry affect cross-channel
synchronization. Open the Regedit applet and set
HKEY_LOCAL_MACHINE\SYSTEM\
CurrentControlSet\Services\VCChd\Parameters\disableC
Csync to zero. Restart the VCCHD driver. If your files are still
getting slightly out of sync with each other, you can modify
HKEY_LOCAL_MACHINE\SYSTEM\
CurrentControlSet\Services\VCChd\Parameters\syncToler
ance in increments of 1. Each time you modify the
syncTolerance entry, restart the VCCHD driver.
Q. How can I receive (and process) callback messages?
A. The HDCom application reports ASCII text callback messages
to a serial controller. It is up to the serial controller to receive,
parse, and use callback messages properly. See Callbacks on
page 16 for the format of callback messages reported by the
HDCom application.
Q. How can I set up a play list?
A. You can play one file after another seamlessly by issuing the
mpgLoadNext command through the HDCom application.
The HDCom application reports callback message 5 (File Read
Start) whenever it is ready to receive an mpgLoadNext
command. You may wish to program a serial controller to
queue files from a list or a database—whenever the serial
controller receives callback message 5, it can read the next file
name from the list or database and send an mpgLoadNext
command.