IBM 2361 Large Capacity Storage
memory storage unit used with certain models of IBM System/360 mainframe
The IBM 2361 Large Capacity Storage (LCS) is an optional component of the IBM System/360 models 50, 65 (when not being used as a multiprocessor), and 75 computers. Storage is implemented using magnetic cores; the cycle time is 8 microseconds and the access time is 3.6 microseconds. This component is also called IBM 2361 Core Storage or IBM 2361 Large Core Storage. It provides additional main storage with a slower access time than the standard storage of the machine—for example 8 microseconds compared to 750 nanoseconds for main storage on the Model 65.
The IBM 2361 was also provided to NASA for use on their IBM 7094 real-time system, where it supplied 524,000 36-bit words of additional memory.
Description
There are two models of the IBM 2361: model 1 has 1,048,576 bytes (1 MB) and model 2 has 2,097,152 bytes (2 MB). The model 2 contains 64 core planes of 32 KB each, the largest core planes ever manufactured.
The IBM 2361 can be shared between two System/360 computers. When sharing is between two model 50s, two model 65s, two model 75s, or a model 65 and a model 75, the two systems must have the same amount of main storage. When one of the sharing systems is a model 50 and the other a model 65 or model 75, the model 50 may have less main storage than the model 65 or model 75.
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