Using the Data Watch Window
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DRUM Summary
DRUM
Instruction
Overview
The DRUM instruction operates on a table of 4x registers containing data
representing each step in a sequence. The number of registers associated with thi s
step data table depends on the number of steps required in the sequence. Yo u can
pre-allocate registers to store data for each step in the sequence, thereby allowing
you to add future sequencer steps without having to modify application logic.
DRUM incorporates an output mask that allows you to selectively mask bits in the
register data before writing it to coils. This is particularly useful when all physical
sequencer outputs are not contiguous on the output module. Masked bits are not
altered by the DRUM instruction, and may be used by logic unrelated to the
sequencer.
Drum Summary
Overview The DRUM summary displays a list of all the DRUM, ICMP and SCIF instructions in
the logic of the current project. They are sorted by their top address. This address’
data is known as its ’Step’ value. All instructions with the same Step value appear
together on the right. All the Step values that are available appear on the list to the
left.
Each row shows the instruction name, its location in logic, and key data values
related to that block. ’Steps Used’, ’Machine ID’. and ’Profile ID’ are all editable
values.
Selecting a Step In the DRUM Summary window:
Note: There may be a delay while a search is performed f or DRUM instructions in
logic.
Step Action
1 Select an address from the left panel and all applicable instructions referencing
that address will be displayed.