Troy Stephen (troys++at++wormald.com.au)
Fri, 13 Jun 1997 16:02:50 +1111 (EST)
I think this subject has been discussed in the past but I can't seem to
find the mailings in the archives.
We have a 3 Pipe Onyx RE2 with the pipes genlocked, and we are finding
that the video refresh rate is dependent on the resolution of the screen:
at 1280x1024 the video refresh is 59.998Hz
at 960x680 the video refresh is 60.833Hz. <--this is the one we are using
The hardware guys assure me that this is perfectly resonable, and I'm not
suggesting that there is anything wrong with our hardware.
The problem is, our Host Simulation program is running on another machine
and maintaining a pretty firm 30.0Hz and the IG is doing ~30.4Hz.
Unfortunately the Host and IG are communicating asynchronously and so the
IG draws an extra frame using stale ownship position data every 2.5
seconds and as a result we get a slight jitter.
Does anybody have any suggestions for me to get around this? We have
thought about syncing the Host off the IG but that is going to cause
problems in other systems due to the curious frame rate that the Host
would have to run at.
What would be ideal is a vme card in the Host machine which generates a
60.0Hz genlock signal to the IG machine and an interrupt to the Host, so
that our frames can be perfectly alligned.
Cheers,
Troy
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