sfcdyn.SFC Dynamic Behaviour on V3.30 target

Product : ISaGRAF Target 3.3x

Date : 13-August-1998

File : sfcdyn.SFC Dynamic Behaviour on V3.30 target.htm

Subject : SFC Dynamic Behaviour on target V3.30

Keywords: SFC - SFC Dynamic behaviour - DEF_SFCEVO_LOW -

DEF_SFCEVO_HIGH

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The SFC dynamic behaviour limits are enlarged on target 3.30.

This modification is activated only for downloaded application with

a format version >= 2.00

More over, IDK customers can force the previous version limit

defining DEF_SFCEVO_LOW or force upper limit defining

DEF_SFCEVO_HIGH

This limitation is in fact linked to the amount of memory allocated

by the kernel at initialization for the sfc engine in order to

manage sfc programs dynamic behaviour.

This amount of memory is calculated as a linear relation with the

number of sfc programms:

Alloc Mem = (Gain * NbrOfSfc + Offset) uint16 (16bits)

where NbrOfSfc is the number of SFC programs,

And 5 allocations of this amount

With DEF_SFCEVO_LOW: Gain = 4, Offset = 9

With DEF_SFCEVO_HIGH: Gain = 8, Offset = 18

Lets call SfcEvo the (Gain * NbrOfSfc + Offset) value.

This number gives, at one or two values more or less, and for each

executed cycle:

The maximum number of transitions nearly valid, that is to say,

transitions with at least one of their previous step being active.

The maximum number of actions to execute. An action is here

an N, P1 or P0 action linked to a step

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