Scanlab RTC6 PCIe Board - List_Jump_Rel

RTC6 boards
Doc. Rev. 1.0.21 en-US
10 RTC6 Commands
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Undelayed
Short List
Command
list_jump_rel
Function Execution produces an unconditional jump to the specified address within the current list.
The next command there is executed immediately without delay.
Call list_jump_rel( Pos )
Parameters Pos Jump distance [(–2
23
+1)…(2
23
–1)].
As a signed 32-bit value.
Comments • list_jump_rel enables implementation of branching (for example, “if-then-else”)
independently of the command’s list position, in particular also coded independently
of the list number because of relative addressing.
• The current list input pointer can be queried by get_list_pointer.
• list_jump_rel is usable in all RTC6 List Memory areas even the protected RTC6 List
Memory “List 3”.
• When specifying a jump distance within “List 1“ or “List 2“ or for non-indexed
subroutines within “List 3” be sure that the jump does not exceed the boundaries of
the corresponding RTC6 List Memory area.
• If list_jump_rel is used in an indexed subroutine or character set, then also be sure that
the jump does not exceed the boundaries of the subroutine or character set.
• Illegal Jump Commands are transmitted unaltered to the RTC6, but are ignored during
processing. Instead, the next command is executed. Hence, the user program does
probably no longer perform as expected. Therefore, Jump Commands must be
carefully programmed (see also Chapter 6.5.3 ”Jumps”, page 120).
• Jump Commands initiating a jump to themselves ( Pos = 0) is also ignored at runtime
to prevent an infinite loop that excludes further activities (and that could only be
halted by stop_execution or an External Stop).
• Decisive are the runtime conditions. When reconfiguring RTC6 List Memory or
converting a subroutine, an originally valid jump address might become invalid due to
new list boundaries or a relocated subroutine storage position.
RTC4RTC6 New command.
RTC5RTC6 Unchanged functionality.
Version info Available as of DLL 600, OUT 600, RBF 600.
References list_jump_pos, list_jump_rel_cond