公开(公告)号：US5627840A

公开(公告)日：1997-05-06

申请号：US529167

申请日：1995-09-15

申请人： Eric K. Hundertmark ,  Duane J. McCrory ,  Todd M. Rimmer

发明人： Eric K. Hundertmark ,  Duane J. McCrory ,  Todd M. Rimmer

IPC分类号： G01R31/3185 ,  G01R31/28

CPC分类号： G01R31/318558 ,  G01R31/318547

摘要： A method and system for optimizing shift operations by reducing the computational overhead and the number of full scan path shifts associated with accessing and modifying data on a rotating scan path image are disclosed. The system further simplifies the construction of a scan path image by inserting a programmable number of leading and trailing bits around a selected string of data bits. The system manipulates and constructs a scan path image without having to shift or prepare the entire scan path image in memory. Specifically, the system comprises a master controller having a lead bypass module, a trail bypass module, a first shift module, a second shift module, a select module and a shift control module. Collectively, these modules comprise the necessary hardware for executing a plurality of shift optimization functions which include lead and trail bypass insertion, non-destructive read, field isolation, field insertion, bit order reversion, bit rotation and simultaneous read and write operation. The system further incorporates shift access windows and status registers for implementing shift operations without system calls.

摘要翻译： 公开了一种用于通过减少计算开销和与在旋转扫描路径图像上访问和修改数据相关联的全扫描路径移位的数量来优化移位操作的方法和系统。 该系统通过在选定的数据位串周围插入可编程数量的前导和后置位来进一步简化扫描路径图像的构造。 系统操纵和构建扫描路径图像，而不必在存储器中移动或准备整个扫描路径图像。 具体地说，该系统包括具有引导旁路模块，路径旁路模块，第一移位模块，第二移位模块，选择模块和移位控制模块的主控制器。 总的来说，这些模块包括用于执行多个移位优化功能的必要硬件，这些功能包括引导和跟踪旁路插入，非破坏性读取，现场隔离，字段插入，位顺序反转，位旋转和同时读写操作。 该系统还包括移位访问窗口和状态寄存器，用于在没有系统调用的情况下实现移位操作