如果我们所开发的设备并不是像航空航天器那样生命攸关或者生产控制那样的关键任务系统,而是像消费电子类那样,即使出现错误也不会造成灾难性后果的设备,那么实时性(严格地讲是确定性)是否还具有现实意义呢?答案是肯定的!设备的高可靠性可以有效地降低维护成本;软件运行效率高也会降低对的要求,从而降低硬件成本。对于消费电子产品这类价格十分敏感的产品,实时性、可靠性仍然是值得重视的问题。
坚如磐石――可靠性
桌面操作系统与RTOS相比,另一个差别就是对于稳定性、可靠性方面的设计思路。一方面,桌面操作系统比较庞大、复杂,而RTOS比较小巧、简捷,而“越简单、越可靠,越复杂、故障概率越大”这又是一个常理。另一方面,更重要的是:桌面操作环境与嵌入式环境在设计思路上有一个重大的不同——桌面环境假定应用软件与操作系统相比而言可以是不可靠的,而嵌入式环境假定应用软件与操作系统一样可靠。
Tektronix TM502A mainframe wth AM503B Current Probe Amp
Tektronix P6015A/2R 25 MHz High Voltage Probe Tested
Tektronix 2465BDV 400 MHz Oscilloscope – LOW HOUR/Cal
PERFORMANCE CALIBRATED! – RETURNS! Freq Cnt/Multimeter
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TEKTRONIX 519 1 GhZ OSCILLOSCOPE
TEKTRONIX VX4240 USPP VX4240
Tektronix 68000 /010/ Probe Adapter
Tektronix TDS 410A TDS410A digital scope, NIST-cal’d
additional free NIST recalibration within one year
Tektronix 2455B 4-Channel 250MHz Analog Oscilloscope
Tektronix 2465 Oscilloscope
Tektronix 11801B 50 GHz Sampling Oscilloscope
Tektronix TLS216 TLS 216 Logic Scope 1F
One-day shipping available
Tektronix PDR 200/PRS 200A Profile Video File Server
TEKTRONIX P6207 4 GHZ ACTIVE OSCILLOSCOPE PROBE TDS820
Tektronix TDS 220 TDS220 oscilloscope, NIST-certified
additional free NIST recalibration within one year
Tektronix WFM601A and 764 Digital Audio Monitor
TEKTRONIX 2465B 400MHz OSCILLOSCOPE + cal’d +guaranty
Tektronix PG506A Oscilloscope Calibration Generator
Tektronix TG501A Oscilloscope Time Mark Generator
Siemens / Tektronix K1297 with Prime E1 Module
TEKTRONIX TDS380 2ch Oscilloscope, 400 MHz, 2 GS/s
Tektronix TDS540A Oscilloscope 500MHz 4Ch 1GSa/s
TEKTRONIX 1450 /1/3/ MAINFRAME
Tektronix TLA7AA4 8S 8Mb 136Ch Logic Analyzer Module
One-day shipping available
Tektronix DSA602A Digitizing Signal Analyzer, 1 GHz
Tektronix SCALCF1 Calibration Fixture
Tektronix 1411 PAL Video Generator Mainframe
Tektronix 1750A NTSC Waveform, Vector, SCH Monitor
Tektronix 2467B 4-Channel 400MHz High Writing Speed Osc
Tektronix 012-1221-00 2 Meter Cable For Sampling Heads
Tektronix 1740-6 Waveform Vector Monitor
Tektronix ST103-RX-TX Sonet Transmission Test Set. Tran
Tektronix 1410 NTSC Video Generator Mainframe
Tektronix P6022 Current Probe Kit
Tektronix TR503 Tracking Generator
Tektronix TDS320-14 100 MHz, Dual Channel, Digital Osci
Tektronix SG504 Leveled Sinewave Generator
Tektronix OCP5002 2GHz Optical Converter / Power Meter
Tektronix VX4355 24 channel switch dpst or spdt relay
Tektronix VX4372 256-Crosspoint Relay Matrix Module
Tektronix VX4342 2 Ch. Resistor Prog.VXI Resistance Mod
Tektronix TLA7M2-1S Logic Analyzer Module
Tektronix 11801C Digital Sampling Oscilloscope
Tektronix DSA602 /4C Digitizing Signal Analyzer DSA 602
Tektronix VX4236 Digital Multimeter VXI Module
TEKTRONIX 2465DMS 300MHZ 4-CHAN OSCILLOSCOPE 2465 DMS
Tektronix TLA7L3 State/Timing Module with Accessories
Tektronix TSG-100 NTSC Television Test Signal Generator
One-day shipping available
TEKTRONIX VFM90
Tektronix 1502C Metalic TDR Cable Tester,YT-1S,Parts
Tektronix 2706 Preselector RF Stepping
Calibrated, 30-day warranty/14-day right of return
TEKTRONIX 760A STEREO AUDIO LEVEL PHASE SCOPE MONITOR
TEKTRONIX TDS 520 2 CHANNEL DIGITIZING 500MHz 500MS/s
Tektronix TDS 430A 2-Channel Digitising Scope 400 MHz
Tested and Working
Tektronix 2235 USM-488 100MHz Dual Channel Oscilloscope
One-day shipping available
TEKTRONIX TDS2014 digital OSCILLOSCOPE 100MHz 1Gs/s 4ch
Tektronix 1103 Tekprobe Power Supply
Tektronix ST2400R Transceiver Fiber Optic Line Test Set
One-day shipping available
Tektronix TDS410A TDS 410A Scope 2ch, 400Mhz Calibraded