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Changing Servo Clock and FTU
#1
I want to raise the servo and phase clock from their default values to 20KHz.
I set Gate1[4].PwmPeriod=2947, Gate1[4].ServoClockDiv=0, Gate1[4].PhaseServoDir=0, and Sys.ServoPeriod=0.0499894884, do a save and reset yet the TaskManager window/Tasks tab still shows the default values. What am I missing? The next step will be to change the Fundamental Time Unit from 1 mSec to 0.1 mSec which I assume can be done by setting Sys.ServoPeriod = Sys.ServoPeriod/10
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#2
Everything looks correct. The frequency will change even without a save and reset. Two possibilities are that maybe a different card than Gate1[4] is the master. Do you have an ACC5E in the rack or any other servo IC cards? Two, Perhaps something is wrong in the task manager as you have a 440 CPU which could run out of gas at those speeds making the task manager timeout and not update. The Task manager uses the following structures. Put them in the watch window and see what they say.

Sys.PhaseDeltaTime
Sys.ServoDeltaTime
Sys.RtIntDeltaTime
Sys.PhaseErrorCtr
Sys.ServoErrorCtr
sys.RtIntBusyCtr
Sys.BgDeltaTime
Sys.MaxServoTime
Sys.MaxPhaseTime
Sys.ServoPeriod
p1=Sys.PhaseCount/Sys.ServoCount p1
Sys.MinPhaseTime
Sys.MinServoTime

Attached is a watch window configuration file that can be directly opened once unzipped. Just right click on the watch table select Properties->control->restore watch table and choose this file.


.zip   CPU Load Watch.zip (Size: 524 bytes / Downloads: 14)

Why do you want to change the FTU? In Turbo PMAC we usually did this because the minimum move time was TA whose minimum was 0 which meant 0.5 msec. Power PMAC has no such limitation, TA, TS, TM are all floating point. The minimum move time is one servo period. At the moment we interpolate through moves smaller than that. In the future when lookahead is finished we will evaluate the angle between moves and only interpolate through them if there is no direction change.
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#3
(04-08-2009, 01:25 PM)brad Wrote: Everything looks correct. The frequency will change even without a save and reset. Two possibilities are that maybe a different card than Gate1[4] is the master. Do you have an ACC5E in the rack or any other servo IC cards?

Yes, there is a Acc5E. How do I find it's address?

Also, thanks on the FTU issue. I was not aware of that.
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#4
(04-08-2009, 02:37 PM)JeffLowe Wrote:
(04-08-2009, 01:25 PM)brad Wrote: Everything looks correct. The frequency will change even without a save and reset. Two possibilities are that maybe a different card than Gate1[4] is the master. Do you have an ACC5E in the rack or any other servo IC cards?

Yes, there is a Acc5E. How do I find it's address?

Also, thanks on the FTU issue. I was not aware of that.

For us old PMAC people the easiest thing to do is enter the PMAC variable of interest in the terminal followed by an arrow. In this case i6800->

PPMAC will report the structure name back to you. If there is no corrsponding structure either because the I-variable no longer exists or the gate array was not detected you get * reported back.
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