IBM J28-200-1 Jan60 1401asm free download

File name J28-200-1_Jan60_1401asm.pdf

t, :J yJ 1401 DATA PROCESSING SYSTEM BULLETIN IBM 1401 SYMBOLIC PROGRAMMING SYSTEM: PRELIMINARY SPECIFICATIONS This bulletin is a minor revision of, but does not supersede, the original edition, form }28-0200. Principal changes are the addition of information regarding the output accompanying the object program (page 10) and the inclusion of Control and Execute commands as part of the Processor Control Operations (page 19). In order to solve a given problem or perform a given function, the IBM 1401 Data Processing System must execute a logical sequence of instructions known as a program. To be meaningful, this program must be written in the actual language of the machine. A program written in this manner is said to be coded in machine language. This method of coding can be time-consuming and prone to clerical and logical errors. Also a hand , coded ma.chine language program, which may represent a great deal of programming effort, is not relocatable; that is, it cannot be executed from a different section of the processing unit without being manually changed. Another difficulty arises when instructions are inserted or deleted after a program has been coded. In this case, all instructions that refer to other instructions must be changed appropriately. In order to simplify the preparation of a program for the IBM 1401 and to minimize the shortcomings mentioned above, the 1401 Symbolic Programming System was developed. Figure 1 is an illustration of a routine written for the 1401. Figure 1a shows the routine as coded in 1401 symbolic language. Figure 1b illustrates the listing of the same routine after it has been assembled into the machine language program. This bulletin is devoted to a description of the preliminary specifications of the 1401 Symbolic Programming System. It also describes, briefly, the basic principles and concepts of symbolic programming in general. A knowledge of programming in actual 1401 machine language is presupposed. The listing, program deCK and operating instructions for the symbolic programming processor will be made available at a later date. The processor for the 1401 Symbolic Programming System is designed to operate on configurations of the 1401 Data Processing System equipped with a 1402 Card Read Punch. @ 1959 and 1960 by International Business Machines Corporation TABLE OF CONTENTS Page Basic Principles and Concepts of Symbolic Programming 3 General Description of the 1401 Symbolic Progr