org.lsst.ccs.subsystems.shutter.ptp

Class PTPInfoReader

java.lang.Object

org.lsst.ccs.subsystems.shutter.ptp.PTPInfoReader

public class PTPInfoReader
extends Object

Sets up ADS notification for changes to the variable MAIN.tinfo in the PLC program running on the Beckhoff CX controller. The dat contains five 64-byte quantities:

1. dctime - The unsigned Distributed Clock (DC) time for the EtherCAT bus, represented as the number of nanoseconds since Jan 1 2000 00:00:00. This is the common time established for all EtherCAT modules which have internal clocks, including the EtherCAT master. The PLC program gets this by calling F_GetActualDcTime64().
2. dctotcoff - The signed offset in nanoseconds of the TwinCAT (TC) time from the DC time. This is a process data item available from the EtherCAT master, which has to be configured to provide it.
4. internalstamp - The unsigned time in nanoseconds of the EL6688 EtherCAT clock. SHould be the same as the DC time.

The main program sets up notification for updates to the "tinfo" variable in the MAIN program of the currently running PLC program, which should be The PTP program of the CCS solution in the CCS Electronics GitHub repository. The PLC program will update the structure at tinfo once a second with the above data, which the Java program will write to stdout. The format is CSV with the first line containing the column headings. All the numbers are in nanoseconds. Each non-header line will start with the TAI time of the system running this Java program followed by the PLC time info variables in the order listed above.

Author:

tether

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	PTPInfoReader.TimeInfo

Method Summary

Modifier and Type	Method and Description
void	close()
PTPInfoReader.TimeInfo	getInfo()
static void	main(String[] args)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

close

public void close()

getInfo

public PTPInfoReader.TimeInfo getInfo()
                               throws InterruptedException

Throws:

InterruptedException

main

public static void main(String[] args)
                 throws org.lsst.ccs.drivers.commons.DriverException,
                        InterruptedException

Throws:

org.lsst.ccs.drivers.commons.DriverException

InterruptedException