Scanlab RTC 5 PC Interface Board Installation And Operation Manual page 211

matically generated when the delay has expired). This
can be useful, for instance, when processing multiple
workpieces transported to the scan system (even) at
irregular intervals: here, up to 8 workpieces can
simultaneously reside within the track delay (distance
between the light barrier and scan system). If more
external starts are triggered than can be simulta-
neously held in the 8-start wait loop, then an error bit
is set, which can be queried via
(bit#11). If a track delay is set, then any previous
queue is canceled (see set_ext_start_delay
simulate_ext_start).
Notes
• Note that the /START, /START2 and /Slave-START
inputs are edge sensitive (HIGH to LOW level
transition), whereas the /STOP, /STOP2 and /Slave-
STOP inputs are level sensitive.
• An explicit call of the command
disables the /START, /START2 and /Slave-START
inputs. An external stop signal also (at least
temporarily) disables these inputs, i.e. as long as
one of the inputs /STOP, /STOP2 or /Slave-STOP is
LOW. The command set_control_mode
used to define whether or not the /START, /START2
and /Slave-START inputs also stay disabled when
the external stop signal is no longer active.
• The command set_control_mode
allows activation or deactivation of the inputs
/START, /START2 or /Slave-START and deactivation
of track delay.
• External starts will also be suppressed after
pause_list, stop_list or
is set). restart_list, stop_execution,
release_wait or an external list stop will end
suppression of the list start.
• If list inputs are not yet finished, a buffer flush
should be initiated before an external start, e.g.
via set_input_pointer( get_input_pointer ()),
so that possibly buffered list commands will be
fully transferred to list memory (see
• If a master board is started internally (e.g. via
execute_list_pos) and subsequently a slave
board via simulate_ext_start, then the master
and slave boards won't run synchronously if a
home jump was previously activated via
home_position or home_position_xyz: the
home return executes on the master board before
simulate_ext_start starts the slave board, but
executes on the slave board afterward. While the
home return executes on the slave board, the
®
RTC 5 PC Interface Board
Rev. 1.9 e
9 Programming Peripheral Interfaces
get_startstop_info
and
stop_execution
can be
additionally
set_wait (PAUSED status
page 71).
master board continues running. This asynchro-
nicity doesn't occur if all boards are started via an
external start signal (or via simulate_ext_start
simulate_ext_start_ctrl) or if no home jump is
activated.
or
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