Clock Synchronization (Windows Drivers)A critical task for the wave sink to do is to resolve time drift between the reference- clock and sample- clock crystals. It does this with the software equivalent of a phase- locked loop. The wave sink keeps track of what sample number in the buffer it can write to next. So even though it knows that it is on, for example, sample 2. It has a thread that wakes up approximately every 2. The master clock might report back that the current time (in milliseconds) is 4. The wave sink also maintains a latency clock, which shows the offset between the current time according to the master clock and the sample time. It uses this information to calculate the expected master clock time and compares this with the actual master clock reading to see if the two clocks have drifted apart. The wave sink uses a phase- locked loop to adjust the sample time. When checking for drift, the wave sink does not adjust by the whole amount, because the readings contain some jitter. Instead, it moves the sample clock by some fraction of the distance toward the master clock. In this way, the wave sink smoothes out jitter errors while staying roughly in sync. It also takes this time and converts it to a latency clock time that is relative to the master clock. This is important because the application might need to know where the synthesizer is rendering at any point. The latency clock tells the application the earliest time at which a new note can be scheduled to play. The latency clock time is the master clock time plus an offset that represents the synthesizer's latency. This latency represents the minimum delay from the time that the application submits a new note to be played to the time that the synthesizer actually plays the note. At any instant, the application can schedule a note to be played at or later than- -but no earlier than- -the current latency clock time. For example, if the master clock is currently at time 4. If the software synthesizer has a latency of 1. Suppose an event is marked to play at time 5. The synthesizer does its work by rendering notes down into samples and performing all its calculations in sample time. Therefore, it needs to know what a reference time of 5. In user mode, the wave sink provides two functions that the synth uses: IDirect. Music. Synth. Sink: :Sample. To. Ref. Time. IDirect. Music. Synth. Sink: :Ref. Time. To. Sample. To do the conversion in this case, the synth calls IDirect. Music. Synth. Sink: :Ref. Time. To. Sample on the wave sink. The wave sink then gives back a sample time (for example, 6. The note in question gets rendered at sample time 6. Then, when the synth IDirect. Music. Synth: :Render method gets called by the wave sink to render the next portion of the stream (for example, from sample time 6. Note. The wave sink also manages synchronization with the master clock and provides latency information. Hiding this functionality in the wave sink makes writing the synth easier. Freeware Time Synchronization. Synchronize your PC time with atomic clocks over the Internet. 24 useful links about Software to display world times, clocks, utc time, timers and world time zones collected in Software/Time at The DXZone. Time synchronization software includes: TimeKeeper from FSMLabs (Linux and Windows) for high performance and low latency applications, and PresenTense from ByteFusion. Windows Insider Program. How do I change that to. Free Time Synchronization Freeware downloads and reviews from Snap. Sync System Clock with Internet TimeIf you're looking for a program to keep your.
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