IBM TIE6309-0235 1401pgmrsGuide free download

File name TIE6309-0235_1401pgmrsGuide.pdf

ITEM NUMBER 6309-0235 (T.I. ~.) 27 pages I)ATE July 31, 1963 AUTHOR Paul I. Bartholet TITLE 1401 PROGRANllv1ERS GUIDE - ELIZABETH OFFICE SOURCE IBM CORPORATION 570 North Broad Street Elizabeth, New Jersey Thtg paper la 1n the author'g orlginal form. The objective In prov1dlng th1g copy i8 to keep you Informed 1n your f1eld of Intereflt. Pleaae do not distrlbute th1s paper to per aona outoide the IBM Company. IBM CONFIDENTIAL . 'STRIBUTED BY 6309 0235 THE: PROGFlAM INFORMATION DEPARTMENT (TIE) IBM CORP. 11 Z EAST POST ROAD WHITE PLAINS .. NY TABLE OF CONTENTS Section I .- Internal Programming Techniques Index Regis ters 1 Summary of Halt Techniques 2 Summary of Negative Zeros 3 Ari thmetic Overflow 4 Console Entry 4 Other 5 Section II - Package Programs Autocoder 7 SPS 7 IOCS 8 RDLIN 10 RPG 11 FARGO 11 AUTOTEST 12 SORT II 14 Section III - Random Access 1405 Testing 16 1311 Direct Seek 16 1311 - Other 19 Section IV - Magnetic Tape Reading and Writing Tape 24 Tape Marks 25 SECTION I INTERNAL PROGRAMMING TECHNIQUES A. Index Regis ters 1. Timing Indexed instructions require three to four additional II I II cycles per addres s indexed and therefore us e additional process time. For example the time to move ten characters with and without indexing is as follows: Wi thou t indexing 322.0 us One address indexed 356.5 us Both addresses indexed 391.0 us As can be seen, indexing increases the process time by more than 10% and 20% respectively. While indexing easily outperforms address modification in terms of both time and core, it may not provide the best solution when dealing 'Nith fields in a tape I/O area. In this case every instruction referring to the I/O area is indexed and the total proces