DigiView's streaming mode uploads sample data while it is being captured, allowing use of the PC's larger memory for extended captures.

Streaming Characteristics

• Uses PC's memory to Extend Storage
• Hardware based compression reduces upload bandwidth, allowing for higher data bandwidth before the USB or PC are overrun. It also means we can keep the data in the PC's memory (rather than on disk), eliminating another bottleneck and source of bandwidth variations.
• Very Large FIFO makes the stream much more immune to high speed data bursts and/or PC 'hiccups' and latency.
• Hardware based trigger circuitry ensures that triggers are reliable. It also means that the PC does not have to process the data stream in real time, allowing us to keep our advanced trigger capabilities, and reduces dependency on the PC's performance.
• Since we do not emulate any of the analyzer's function in software, we do not need to process the real-time data stream at all. It is simply transferred to memory as quickly as it arrives; again, enhancing reliability.

We start with the rock-solid reliability of using local, full-bandwidth storage and real hardware triggers. Then we layer a hardware-supported streaming capability on top of that hardware. We added the streaming mode to enhance the total capture time - NOT to save hardware. In fact, we added more hardware to add this mode.

All of this hardware support results in very reliable streaming at full sample rates and very high data rates. However, there is still a concern: Even though these data rates approach or even exceed the maximum data rates you would normally try to capture at our maximum sample rates, there are times when you have to work on the edge. Sampling at only 2 or 3 times the data rate results in high edge uncertainty and low fidelity waveforms, but sometimes you have no choice. Also, if you only have USB2 ports, your limits are much lower. In these extreme cases, you could still overrun the streaming mode.

We feel the capture should never fail or abort...no matter what. To meet those standards, we accommodate these edge cases by also including our traditional store-and-forward mode and an automatic fall-back mechanism.

DigiView's Hybrid Controller starts in streaming mode. If the long-term average data rate exceeds the streamable limit, the hardware predicts the over-run and seamlessly falls-back to store-and-forward mode without loosing any data. All trigger settings are still honored. If a trigger was not detected before the fallback, the hardware will continue looking for it, honoring the prefill setting.

See the 'Streamable Data Rate Chart' below for the approximate streaming data-rate limits.

• Guaranteed full data bandwidth operation at full sample rate
• Not dependant on PC, USB, or Windows performance
• Extensive hardware support ensures Extended storage in all but the most extreme cases
• All functionality implemented in real hardware
• User does not need to select mode; The Hybrid Controller auto-adapts
• Dependable
  • Never Over-runs
  • Never misses a sample
  • Never misses a trigger
  • Never says 'reduce sample rate'
  • Never says 'try again'