User`s manual

Alcorn McBride Digital Video Machine HD User’s Manual Rev 1.0
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Q: I am trying to play a video file on the DVMHD. I hear audio, but the video output is
black. What’s happening?
A: The video portion of your file is most likely not compatible with the DVMHD for one
reason or another. Perhaps it was encoded with a 4:2:2 chroma format (whereas the
DVMHD only supports 4:2:0)? Another common mistake is encoding the file for
1080p60, which is not supported by the DVMHD. To fix the problem, use the
information provided in the Media Files section to change the appropriate setting(s) of
your encoding software, and re-encode the video with a supported format.
Q: Do you have a basic checklist I can go by in order to figure out what’s wrong?
A: Here’s a checklist we have compiled of typical things you can check to make sure
all the bases are covered:
• Is the unit plugged in? (bear with us)
• Does the unit have a Compact Flash card in it at all? (remove the front metal
plate & check)
• Is the Compact Flash card pressed in all the way?
• Validate you’ve used the A/V cables somewhere else successfully. Verify
your display works, etc…
• If you are using a serial cable, is it straight through (as opposed to a null
modem)?
• Are your video files compatible with the DVMHD? See Media Files section.
• Are your file name formats valid? See Media Files section.
• Take every other piece of control equipment away from the unit, making it
stand-alone until you get it running. Try to make sure it operates using the
‘Play Test File’ function on the front-panel menu. You can also send serial or
Ethernet commands from a laptop or PC.
• If the unit does not respond to serial messages typed by hand or from
another system:
o Are you sure you’ve chosen the correct COM port on your PC? Are
you communicating using 9600 baud,8 data bits, no parity, and 1
stop bit (9600,8,N,1)?
o Are you using a straight-through (not NULL) RS-232 cable?
o Are you using the correct commands listed in the Command
Protocol Section? Can you get a version number from the box by
using a terminal emulator, or AMI Terminal?
• Is the Compact Flash Card damaged? Do you have a second Compact
Flash card you can temporarily use to make sure the Compact Flash Card
isn’t just damaged? Go through the file copying process with the new
Compact Flash Card, and try to play the file.
•
Is the unit damaged? If you can put another Digital Video Machine in the
circuit, you can rule out the possibilities of a damaged unit. Remember to
use the same Compact Flash card.