Matrox Morphis QxT, Installation And Hardware Reference

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Overlay 39
There are three main timers that make up the Watchdog circuitry:
• Warning timer. If, during the course of regular operations, the Host computer
does not reset the warning timer before the specified interval expires, it is assumed
to have hung. The Watchdog’s warning timer will then generate a warning
interrupt.
• Timeout timer. If, during the course of regular operation, the Host computer does
not reset the timeout timer before the specified interval expires, it is assumed to
have hung. The Watchdog’s timeout timer will then force the Host computer to
reboot.
• Reboot timer. If, during a reboot, the Host computer does not start regular
operations before the specified interval expires, the Host computer is assumed to
have hung. The Watchdog’s reboot timer will then force the Host computer to
reboot again.
You can enable the Watchdog circuitry and set and reset the Watchdog timers
using the MIL-Lite
MsysControl() function. You can hook an event handler
function to the warning interrupt using MsysHookFunction() .
Overlay
The overlay processor can overlay information onto grabbed images. The overlay
operation can be done before the image is sent to the MPEG-4 encoder, or before
the image is sent to the Host. The overlay processor can block part of the source
image, or blend information with the image (with a programmable alpha factor),
using the MIL-Lite
MbufTransfer() function .