Reference Manual

PMAC 2 Software Reference
312 PMAC Program Command Specification
DWELL
Function
Dwell for Specified Time
Type
Motion program (PROG and ROT)
Syntax
DWELL{data}
DWE{data}
where:
• {data} is a non-negative floating point constant or expression representing the
dwell time in milliseconds.
Remarks
This command causes the card to keep the commanded positions of all axes in the
coordinate system constant for the time specified in {data}.
There are three differences between DWELL and the similar DELAY command. First, if
the previous servo command was a blended move, there will be a TA time deceleration to
a stop before the dwell time starts. Second, DWELL is not sensitive to a varying time
base – it always operates in ‘real time’ (as defined by I10). Third, PMAC does not pre-
compute upcoming moves (and the program lines before them during the DWELL; it waits
until after it is done to start further calculations, which it performs in the time specified
by I11 or I12.
Use of any DWELL command, even a DWELL0, while in external time base will cause a
loss of synchronicity with the master signal.
Example
DWELL250
DWELL(P1+P2)
DWE0
See Also
Dwell and Delay (Writing a Motion Program)
I-variables I10, I11, I12.
Program command DELAY
ELSE
Function
Start False Condition Branch
Type
Motion program (PROG only), PLC program
Syntax
ELSE (Motion or PLC Program)
ELSE {action} (Motion Program only)
Remarks
Warning:
With nested IF branches, be careful to match the ELSE statements to the
proper IF statement. In a motion program, it is possible to have a
single-line IF statement (IF({condition}) {action}). An
ELSE statement on the next program line is automatically matched to
this IF statement. Put a non-ELSE statement in between to make the
next ELSE statement match a previous IF statement.
This statement must be matched with an IF statement (ELSE requires a preceding IF,
but IF does not require a following ELSE). It follows the statements executed upon a
true IF condition. It is followed by the statements to be executed upon a false IF