嵌入式系统为什么对实时性要求那么高呢？因为嵌入式系统主要是对仪器设备的动作进行监测控制的，而一般的桌面操作系统基本上是根据人在键盘和鼠标发出的命令进行工作。相对而言，仪器设备的动作具有严格的、机械的时序要求，而人的动作和反应在时序上并不那么严格。比如，用于控制火箭发动机的嵌入式系统，它所发出的指令不仅要速度快，而且多个发动机之间的时序要求严格，否则就会差之毫厘、谬之千里。在这样的应用环境中，非实时的普通操作系统无论如何是无法适应的。
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
Thermolyne S-7225 Aluminum Top Stirrer 7” x 7”
Square D SY/MAX RIM-121 Standard Analog Input Module
Square D SY/MAX Model 400 Processor w/ Key
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Symbol SPT1800 Series Palm Powered Barcode Scanner
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Siemens ED22B100 Circuit Breaker 100A 2Pole 240-250VDC
Siemens Sirius 3RT1044-1BB40 Motor Starter Contactor
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SKF LBCR30-2LS Linear Ball Bearing Qty. 7 NEW
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Roland Teaching Laboratory System Console TL-16
Rose Electronics ServeView SVE-16UA 16-Port KVM Switch
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Savant HSC-10K-AC High Speed Benchtop Centrifuge
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