描述
PLC还要完成内部处理、通信处理等工作，一次循环可分为5个阶段（见图1-5）。PLC的这种周而复始的循环工作方式称为扫描工作方式。由于计算机执行指令的速度极高，从外部输入-输出关系来看，处理过程似乎是同时完成的。
NetApp X272 Network Appliance 72GB FC 1 YR WARRANTY
NetApp X235 Network Appliance 72GB FC 1 YR WARRANTY
NetApp X266A 320GB ATA TO FC DS14MK2 AT
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NETAPP X5610A AT-FC MODULE (HSSDC2-HSSDC2)
NETAPP X5610A 106-00024 Cu Copper AT-FC SCM Module
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NetApp X1941A 5m 4X IB Cluster Cable 112-00037
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NetApp FAS2020 ,FAS2040, FAS2050. SAS to FC BRACKET
