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used as the starting point for the motion initiate. If the motion time base is realtime, then the captured time is used as the starting
point for the motion profile. If the motion time base is synchronized, then the captured master position is used as the starting point for
the profile.
Example:
Wait For (Capture.0.CaptureTriggered)
Index.0.Initiate Using Capture.0
Using Last
When the Using Last instruction is inserted after a motion initiate instruction, the time (or master position in synch motion) of the last
command complete is used as the starting point of the motion profile. Whenever a motion profile is complete, the time/position is
automatically captured behind the scenes. The Using Last instruction simply references this "automatically" captured time or
position.
EZMotion performs motion based on a concept called the timeline. The timeline allows for accurate and repeatable motion with
respect to a single point in time. The timeline guarantees that all motion profiles occur at the right time with respect to each other.
If Index0 takes 3 seconds to complete, and Index1 takes 5 seconds to complete, by initiating Index0 and then Index 1 in a program,
the user would expect these profiles to take a total of 8 seconds to complete. It is possible though, that because of processor timing,
Index.1 does not start at exactly the same time Index0 is complete. Therefore, the two profiles could take slightly more than 8
seconds to complete. Although the amount of time lost is extremely small (less than 5 milliseconds), over a long period of time, this
lost time can accumulate.
Keeping the timeline intact is most important in applications using synchronized motion. This is because in synchronized motion,
time is replaced by master encoder motion. If time is lost in a synchronized motion application, then master distance is lost, and the
follower position is off with respect to the master.
Example:
Index.0.Initiate
Dwell For Time 1.000 Using Last
Index.1.Initiate Using Last
9.9
Red Dot Error Bar
The Red Dot Error Bar is used to display if an error exists on a particular line of code in the user program. PowerTools Pro uses a
program parser that reads the user program, and translates it directly into the language that the EZMotion processor understands. If
the parser detects a mistake (i.e. syntax error) in an instruction, a Red Dot will appear next to that line of code in the Red Dot Error
Bar.
To find out what the error is, PowerTools Pro has a utility called Red Dot Help. To use Red Dot Help, click the Red Dot Help button
on the program toolbar. This will place PowerTools Pro into "Red Dot Help Mode". While in this mode, the mouse pointer should
have a red and yellow question mark next to it. After going into Red Dot Help Mode, simply click on the line of the program that has
a red dot next to it. Some description of the error should appear that helps indicate what the error is, or how to fix it. When finished
checking Red Dot Errors, click Red Dot Help button on the program toolbar to exit Red Dot Help Mode.
A user program that has a red dot on an empty line often indicates that the second part of a two-part instruction is missing (i.e Do
While with a missing Loop, If with a missing EndIf, etc.).
If a variable or parameter name is spelled incorrectly, the Red Dot Help message will indicate "XXXX" Error - Couldn't find Variable
named from Text" (where XXXX is the parameter name typed by the user). If this message is displayed, make sure that the
parameter names on the specific line are spelled correctly.
9.10
Program Code Window
The Program Code Window is where the program instructions are inserted to create the user program.
Program instructions can be inserted into the Program Code Window using either one of two methods. The two methods available
are drag & drop or type the instructions into the window.
Drag & Drop Method
The most popular method for inserting program instructions is to drag the instruction from the instruction list and drop it into the
program window. To drag & drop an instruction, position the mouse pointer over the instruction to be inserted. Press and hold the left
mouse button. While holding the left button, place the mouse pointer on the line of the program that the instruction is to be inserted
on. Release the left button to insert the instruction.
Typing Method
Once users become more familiar with the syntax of the EZMotion programming language, they often prefer to type instructions in.
To do this, simply click the left mouse button on the line of the program where instruction is to be inserted. Then simply type the
instruction on that line, being sure to use proper syntax.
The user can enter program code using both methods interchangeably.
9.11
Program Blocking
A user program (or task) can be blocked from operation for a period of time. When a program or task is blocked, execution is simply
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EZMotion User/Programming Guide
Revision: A8
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