User guide
210
6000 Series Programmer's Guide
Synchronizing
Following Moves
with Master
Positions
A final special case allows perfect synchronization between the start of a Following motion
profile of a slave axis and a specified position of its master. If a GOWHEN(nPMAS >=
xxx) expression is used to synchronize a slave with its own master, with the operator
specifically “>=”, a special synchronization occurs. Although it may be impossible for the
6000 product to sample the exact master position specified, the Following motion profile is
calculated from master travel based on that position. This allows for the construction of
profiles in which the synchronization of master and slave positions is well defined and
precisely maintained. This feature requires positive travel of the master, which can be achieved
with the appropriate sign for the FOLMAS specification.
Summary of Master Cycle and Wait Commands
FMCLEN ............................. Defines the length of the master cycle
FMCNEW ............................. Immediately restart master cycle counting
FMCP................................. Defines the initial position of a new master cycle
GOWHEN() .......................... GOWHEN() suspends execution of the next move on the specified
axis or axes until the specified conditional statement (based on T,
IN, FB, NMCY, PC, PE, PM, PMAS, PSLV, or PSHF) is true
TNMCY
or [ NMCY ].............. Transfers or assigns the current master cycle number
TPMAS
or [ PMAS ].............. Transfers or assigns the current master cycle position
TRGFN ............................... TRGFNc1xxxxxxx initiates a GOWHEN, suspending execution of the
next slave move until the specified trigger input (c) goes active.
TRGFNcx1xxxxxx causes master cycle counting to restart when
the specified trigger input (c) goes active.
WAIT() ............................. WAIT() suspends program execution until the specified
conditional statement (based on PMAS, FS, NMCY, PSHF, PSLV, or
VMAS) is true;
WAIT(SS.i=b1) suspends program execution until a trigger
input is activated. The “i” is the programmable input bit number
corresponding to the trigger input. (Input bit assignments vary
by product; refer to the Programmable I/O Bit Patterns table on
page 107 to determine the correct bit pattern for your product.)
AS
and TAS bit #26.................. AS and TAS (and TASF) bit #26 is set when there is a profile
suspended pending GOWHEN condition, initiated either by a
GOWHEN command or a TRGFNc1xxxxxxx command; this bit is
cleared when the GOWHEN condition is true or when a stop or kill
command is issued.
ER
and TER bit #14.................. ER, TER, and TERF bit #14 is set if the GOWHEN condition is
already true when the GO, GOL, FSHFC, or FSHFD command is
given (ERROR bit #14 must first be enabled to check for this
condition)
NOTE
The continuous cut-to-length application example below illustrates the use of the master
cycle concept and the commands above.