Appendix D Time Sync Implementation - GE Kelman DGA900 Operator's Manual

The product has a time-sync feature that allows users to synchronize the clock. This
Appendix explains the data format options for the "time sync" and its implementation.
D.1 Time Format
Under the standard Modbus® register list, the timing is defined in Table D-1.
Table D-1: Timing
Register Permissions
1200
1201
R/W
1202
1203
This R/W (read/write) register is in BCD format (Binary Coded Decimal). Some systems are
not compatible with this data format. *The time registers can be written separately in 5
second intervals in any order.
D.2 UNIX® Epoch register
A UNIX Epoch register was added to the host board firmware (v1.12.2) to make systems
integration easier in cases of system incompatibility. Both register formats (BCD & UNIX)
will be maintained in future firmware versions and both affect the same single clock. The
details of the UNIX time registers are listed in Table D-2.
Table D-2: UNIX time registers
Register Access
Flags
1197 rg2,wg2
1198
These registers are readable and writable, but should be written together as a single 32-bit
value.
D.2.1 UNIX Time Format
The number of seconds from the UNIX epoch time of Jan 1st 1970 00:00:00.
D.2.2 UNIX Time Example
For reference, the time on a device is reported in the UTC format on the HMI as 11/29/2017
00:00:00 BST and the corresponding value in the registers mentioned above is
1511913600.
MA-025 – DGA 900 Operator Guide – Rev 2.0
Appendix D
Group
Description
Size
UTC Clock: Years
UTC Clock: Months, days
4*
UTC Clock: Hours, minutes
UTC Clock: Seconds, Day of week
(0-6, 0 Sunday)
Version Storage Effect
Class After
1.12.2 RAM immediately
Time Sync Implementation
Data Format
YYYY (BCD)
MMDD (BCD)
HHMM (BCD)
SSWW (BCD)
Name Description
RTC_UNIX_ Current Time UTC
TIME in UNIX format
12-Apr-19
Data
Format
32-bit
integer
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