Rockwell Automation 1771-DMC_DMC1_DMC4_DXPS Control Coprocessor User Manual - Manual (Page 174)

API Library of Routines
Appendix B
DTL_CLOCK
B-43
Sets the control-coprocessor date and time to the same date and time found
in the PLC-5 programmable controller.
Syntax
#include <copro.h>
unsigned DTL_CLOCK ()
Description
DTL_CLOCK synchronizes the control coprocessor time to within one
second of the clock for the PLC-5 programmable controller. This is a
one-time-only synchronization. The user can maintain synchronization by
executing DTL_CLOCK at regular intervals.
Since this routine performs I/O to the PLC-5 programmable controller, the
calling process must call DTL_INIT prior to calling DTL_CLOCK.
Returns
Status Symbolic Name Meaning
0 DTL_SUCCESS Operation successful
18 DTL_E_TIME I/O operation did not complete in time
19 DTL_E_NO_INIT DEFINE tablenot initialized
42 DTL_E_GETIME PLCĆ5 timeinvalid
C Example
unsigned status;
status = DTL_INIT (1);
status = DTL_CLOCK ();
DTL_CLOCK