Owner's manual

7-12 Advanced Programming
7.4.1.1 Loop Block Command
Loop Block commands define the number of passes for multipass patterns. When you define a loop,
FmXP inserts
Loop Pass: from 1 to X (X represents the total number of passes) and Next Loop:
commands into your program.
7.4.1.2 Pass Block Command
Pass Block commands are used to setup multipass patterns. When you create a multipass Pattern, FmXP
inserts a
Start Pass and End Pass command into your program. The number of Start Pass/End Pass sets
should equal the number of passes you wish to setup. The dispensing commands for each pass are
inserted between the Start and End Pass commands.
7.4.1.3 Multipass Timer
You also have the option to set timers during the dispensing process. For example, you may want to make
sure the fluid flows completely underneath the chip before the sealant is dispensed.
• Await Multipass Timer
- Await Multipass Timer should be the first command in every Pass
of a multipass pattern, except for the first pass. Await Multipass Timer works in
conjunction with Reset Multipass Timer.
• Wait Time
- Enter the number of seconds you want to wait between passes. Take all fluid
characteristics into consideration when you set the Timer.
• Reset Multipass Timer
– Reset Multipass Timer should be the last command in every Pass
of a multipass pattern, except for the last. When you select Reset Multipass Timer, the
Timer is set to 0 and a Reset Multipass Timer command is inserted directly into your
program. If the indicated wait time has not expired before FmXP is ready to begin the next
pass, then the Await Multipass Timer dialog box opens containing a timer and a message.
The timer counts down the remaining seconds before the next pass is executed.
7.4.2 Weight Control on Multiple Passes
Weight control lines are usually used for all lines in multiple pass programs. Different line styles are
sometimes defined for each line of the program. For instance, the first L-shaped line in an L-shaped
pattern usually is defined with a higher weight than the second L-shaped “seal pass”. This assumes that
the fluid will flow underneath the die to the opposite corner.
7.4.3 Reusing Fiducials and Height Sense Information
If your workpiece contains many parts, and the pattern to be dispensed is a two or three-part pattern such
as the L-shaped and U-shaped patterns, checking fiducials and the substrate height during every pass can
be time consuming. In many cases, it is unnecessary since the likelihood that the parts could move before
the timers expire is very low. Rather than finding fiducials and doing a height sense check during every
pass, fiducials and height sense checks are performed once for each part and the information is stored
and reused during the second pass. This is called “Reusing Fiducials” and is enabled by selecting
Pass
Block from the Pattern button cascading menu on the Program Commands toolbar. This feature is a
significant timesaving option.