Scanlab RTC 5 PC Interface Board, Инструкция по установке и эксплуатации

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RTC
®
5 PC Interface Board
Rev. 1.9 e
10 Commands And Functions
239
innovators for industry
Ctrl Command auto_change_pos
Function activates a one-time automatic list change and simultaneously defines the list position at
which execution will continue.
Call
auto_change_pos( Pos )
Parameter
Pos
Start position (list memory address) as an offset referenced to the beginning
of the list to be started via the automatic list change (as an unsigned 32-bit
value)
Comments • The auto_change_pos command triggers a subsequent one-time-only list change or a
list new start. For further list changes or list new starts, the command must be called
again.
• The command can be issued at any desired time point.
• If the automatic list change is activated during processing of a list, then upon reaching
set_end_of_list execution will continue without delay at the supplied start position of
the other list. If there is only one list (
Mem2
= 0, see config_list ), then upon reaching
set_end_of_list execution will continue at the supplied start position of this list.
• During processing of a list, the other list (and also the current list) can be newly loaded
(see "Automatic List Changing", page 75 ).
• So that auto_change_pos can function at all, any already active list must absolutely be
finalized via set_end_of_list ; the new list should already be loaded and the input
pointer should be sufficiently ahead of the output pointer (otherwise, “old” commands
will be executed). If, during list execution, the end of the list is reached without encoun-
tering a
set_end_of_list , then execution will automatically continue at the beginning
of the current list.
• If an automatic list change is activated when no list is currently being processed, then
checking will take place as to whether a list was already processed and the other list
was started (at the supplied start position). If no list was previously executed, then
“List 1” will be regarded as already executed (initialization) and “List 2” will be started.
• If a list memory address outside the corresponding list area is supplied (depending on
which list should be started:
Pos

Mem1
or
Pos

Mem2
), then the start position will be
set to the beginning of the list (
Pos
= 0).
• If, during processing of a list, the auto_change_pos (
Pos
>0 ) and start_loop
commands are called, then upon the next set_end_of_list the command
auto_change_pos (
Pos
>0 ) will be executed; and at the next one the start_loop
command will be executed.
• The current list and list execution statuses can be queried via the commands
read_status (page 390) and get_status (page 281) .
• The auto_change_pos command triggers a flush of the list input buffer (see page 71 ).
RTC
®
4

RTC
®
5 essentially unchanged, however:
The list memory address (
Pos
) is supplied to the RTC
®
5 as a relative memory address
referenced to the beginning of the respective list, whereas the RTC
®
4 is supplied an
absolute memory address (0…7999). If no memory area is assigned to “List 2” via
config_list (
Mem2
= 0), then the RTC
®
5 command behaves like the RTC
®
4 command.
References auto_change , get_status , read_status