Acc5e JHW Port

[wehg]

In a Power PMAC system, how do I read a quadrature encoder on the Acc5e handwheel port?

 

Thanks

[steve.milici]

The ACC-5E uses a “Gate2” MACRO IC so the setup is just like a PMAC2-style servo IC using software “1/T” timer-based extension of the count. This is a “Type 3” conversion, but with the elements of Gate2.Chan[j].{element name} (note that Acc5E is a valid alias of Gate2). The following saved setup elements must be specified:

EncTable[n].Type = 3 // Software 1/T extension of count value

EncTable[n].pEnc = Acc5E.Chan[j].ServoCapt.a

EncTable[n].pEnc2 = Acc5E.Chan[j].TimeBetweenCts.a

EncTable[n].ScaleFactor = 1/512 // Scale output in whole counts

Motor[x].pEnc = EncTable[n].a // Use table result for position-loop feedback

Motor[x].pEnc2 = EncTable[n].a // Use table result for velocity-loop feedback

 

You can now look at the motor position for the motor number (x in the above) you used.

[curtwilson]

You read them in the same way you would read a quadrature encoder on an ACC-24E2x board. The two servo channels in the "Gate2" IC of the Acc-5E each have a structure that is identical to each of the four servo channels in the "Gate1" IC of an ACC-24E2x board.

 

So you can use Gate2.Chan[j].ServoCapt of an Acc-5E (the encoder count value latched on the servo clock) just as you use Gate1.Chan[j].ServoCapt on an Acc-24E2x board. The 1st handwheel (HW1) on an Acc-5E goes into Chan[0]; the 2nd handwheel (HW2) goes into Chan[1].