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Memory Dumping Between Two Direct Channel Connected Central Processing Units

IP.com Disclosure Number: IPCOM000086247D
Original Publication Date: 1976-Aug-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 3 page(s) / 79K

Publishing Venue

IBM

Related People

Bogardus, RT: AUTHOR [+2]

Abstract

An IBM System 370 and an IBM System 7 are direct-channel connected and a memory dump of the System 7 is required for program debug. Solution

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Memory Dumping Between Two Direct Channel Connected Central Processing Units

An IBM System 370 and an IBM System 7 are direct-channel connected and a memory dump of the System 7 is required for program debug. Solution

Produce System 370 and System 7 programs that will pass the contents of the System 7 memory up to the System 370 for printing on the System 370 high- speed printer. Implementation

Since the two systems are direct-channel connected, communications between them can be handled directly with IBM supplied macros. A 32000-byte record size was selected for the S/7 memory data being transmitted to the S/370. This required the segmentation of the S/7 memory into four such records; therefore, four codes were set up for this purpose. A 16-byte S/370 request record was selected where the first two bytes contained one of the four segment codes.

In order to dynamically select which segment or segments were desired, an input parameter was developed for the S/370 program. This parameter consisted of four bytes of data, each one representing a segment of S/7 memory. To select a segment, set that parameter position to its position number. Any other value in that position negates that segment.

A parameter of `1234' would select all four segments, while a parameter of 'X2XX' would select only segment two. The S/370 program provides a return code upon completion. A value of zero indicates successful completion, a value of four indicates an invalid input parameter, and a value of eight indicates a communication error. Fig. 1 SYSTEM/370 Block Description of Flow Chart Shown in Drawing (Fig. 1) A1 Start S/370 processing of DUMPS7 program. B1 Set the return code variable to 0. C1 Validate input parameter (segment selector). D1 Set the return code variable to 4 if input parameter is invalid. C2 Open files WRITES7, READS7, OUTPUT. D2 Set index variable to 1. E2 Does the input parameter request the segment number contained in the index variable? E3 Build a request buffer for the s...