Specification and implementation of the Universal Time Coordinated Synchronization Unit (UTCSU)

被引:17
作者
Schossmaier, K [1 ]
Schmid, U [1 ]
Horauer, M [1 ]
Loy, D [1 ]
机构
[1] VIENNA TECH UNIV,DEPT COMP TECHNOL,A-1040 VIENNA,AUSTRIA
基金
奥地利科学基金会;
关键词
real-time systems; external clock synchronization; Universal Time Coordinated (UTC); Adder-Based Clock (ABC); linear continuous amortization; accuracy intervals; Application Specific Integrated Circuit (ASIC); very high speed integrated circuit Hardware Description Language (VHDL); Global Positioning System (GPS);
D O I
10.1023/A:1007953214631
中图分类号
TP301 [理论、方法];
学科分类号
081202 ;
摘要
High-accuracy external clock synchronization can only be achieved with adequate hardware support. We analyze the requirements and present the specification and implementation of an ASIC running under the acronym UTCSU dedicated to that purpose. It is built around an elaborated local clock, which is based on an adder driven by a fixed-frequency oscillator. This novel clock design allows a fine grained rate adjustability apt for maintaining both local time with linear continuous amortization and accuracy information as needed in interval-based clock synchronization. Additional features incorporated in our UTCSU are facilities to timestamp clock synchronization data packets, interfaces to couple GPS receivers, some application support as well as sophisticated self-test machinery. Apart from addressing design and engineering issues of the chip, we also provide a basic programming model.
引用
收藏
页码:295 / 327
页数:33
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