- Overview
- Configuration
- NTP4 Plug-In
- Hardware
- RFC 868
- RFC 2030
-
RFC 1305
- RFC 1305
- 1. Introduction
- 1.1 Related Technology
- 2. System Architecture
- 2.1 Implementation Model
- 2.2 Network Configurations
- 3. Network Time Protocol
- 3.1 Data Formats
- 3.2 State Variables and Parameters
- 3.2.1 Common Variables
- 3.2.2 System Variables
- 3.2.3 Peer Variables
- 3.2.4 Packet Variables
- 3.2.5 Clock-Filter Variables
- 3.2.6 Authentication Variables
- 3.2.7 Parameters
- 3.3 Modes of Operation
- 3.4 Event Processing
- 3.4.1 Notation Conventions
- 3.4.2 Transmit Procedure
- 3.4.3 Receive Procedure
- 3.4.4 Packet Procedure
- 3.4.5 Clock-Update Procedure
- 3.4.6 Primary-Clock Procedure
- 3.4.7 Initialization Procedures
- 3.4.7.1 Initialization Procedure
- 3.4.7.2 Initialization-Instantiation Procedure
- 3.4.7.3 Receive-Instantiation Procedure
- 3.4.7.4 Primary Clock-Instantiation Procedure
- 3.4.8 Clear Procedure
- 3.4.9 Poll-Update Procedure
- 3.5 Synchronization Distance Procedure
- 3.6 Access Control Issues
- 4. Filtering and Selection Algorithms
- 4.1 Clock-Filter Procedure
- 4.2 Clock-Selection Procedure
- 4.2.1 Intersection Algorithm
- 4.2.2. Clustering Algorithm
- 5. Local Clocks
- 5.1 Fuzzball Implementation
- 5.2 Gradual Phase Adjustments
- 5.3 Step Phase Adjustments
- 5.4 Implementation Issues
- 6. Acknowledgments
- 7. References
- Appendix A
- Appendix B
- Appendix C
- Appendix D
- Appendix E
- Appendix F
- Appendix G
- Appendix H
- Appendix I
- Time Tools
- NTP Auditor
- About
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Windows Time Server
Hopf PCI DCF77/GPS ReceiverHopf Elektronik manufactures GPS satellite clocks as well as radio clocks designed for the DCF77 time signal broadcast by the National Institute of Natural and Engineering Sciences in Germany. This driver supports the Hopf Elektronik clock model 6039 PCI board. Both, the DCF and GPS variants are supported. You may visit Hopf Elektronik on the web at http://www.hopf-time.com , or email technical support at info@hopf.com.
Hopf 6039 PCI-Bus Receiver
Hopf 6039 Operation
When the unit is slotted into an internal PCI bus of a personal computer and connected to its external GPS antenna, the Hopf 6039 diagnostic software will display the synchronization status of the unit on the Date & Time tab in the Status field. Satellite signal strength is displayed on the Satellites tab. When the Hopf 6039 clock has successfully synchronized to satellite time or DCF77 time, the status indication changes to "clock is radio synchronous with crystal control standard time" as shown below. If you wish PresenTense Server to use the timestamps obtained from your Hopf clock prior to this stage, see "flag1" under Driver Tunables at the bottom of this page.
Hopf 6039 Benchmark Tests
The Hopf 6039 PCI bus board has performed extremely well in benchmark tests with sub-millisecond accuracy.
Driver tunables :
Tunable |
Values/Units |
Description |
time1 |
seconds |
offset calibration factor |
refid |
one to four letters |
server identifier, default GPS or DCF |
flag1 |
0 or 1 |
Use value 1 to force synchronization when only "crystal driven". |