Mainframe Training : COBOL Basic Programming for Assembler Programmers

COBOL Basic Programming for Assembler Programmers

Mainframe Training Overview

Students will gain hands on experience through a series of class discussions and hands-on exercises that include several modifications to an initial working COBOL program.

Throughout the course, COBOL components are compared and contrasted with their Assembler Language counter parts. These include DS/DC vs PIC, DCB vs SELECT/FD, Compiler Assembler instructions, S0C7 abend dumps and arithmetic comparisons.

The course starts with an overview of structured programming concepts.

Development of clear and understandable program designs is stressed along with building maintainable programs. Program debugging techniques are also discussed.

The four divisions of a COBOL program and their functions are reviewed in detail. The syntax rules for these COBOL divisions are also covered in detail.

Character and numeric variables, file processes, file status checks, program loops, conditional statements, arithmetic statements and print a report with headers and trailer are presented as the more common uses of COBOL.

Several COBOL language features are discusses in detail including Reference Modification, Figurative Constants, Special Registers, INITIALIZE, SET, STRING, COPY, Arithmetic statements, process tables via SEARCH / SEARCH ALL, Internal SORT, S0C7 abend, Intrinsic Functions, Calls to LE, and COBOL internal representation.

Performance-based Objectives

As a result of the class, the student will be able to -

compared / contrasted COBOL components with their Assembler Language counter parts
design and develop structured programs
debug a COBOL program's logic via displays and walk-thrus
define variables and build program procedural code
READ and WRITE files
analyze the File-Status field
use IF, EVALUATE, PERFORM statements and use explicit scope (END-) terminators
use arithmetic statements
load / process COBOL tables via indexes / subscripts
code COBOL Intrinsic Functions
code COBOL calls to the Language Environment (LE)
define / discuss the internal descriptions of data in a COBOL program
analyze a program S0C7 abend
compared and contrasted COBOL components with their Assembler Language counter parts

Mainframe Training Audience

This course is intended for Assembler Language programmers / analysts who must understand, design, code, test, and debug COBOL programs from an Assembler Language viewpoint.

Mainframe Training Prerequisites

Six months experience with TSO/ISPF is required.
Six months of Assembler Language coding experience is required.
No previous COBOL experience is needed

Mainframe Training Course duration

5 Days

Mainframe Training Course outline

Day 1 - COBOL Introduction

I. Introduction to Structured / Program Design Techniques

II. COBOL Language Components - 4 Divisions - Identification, Environment, Data, Procedure

A. Syntax Rules
B. Sample Program Examples

III. File Operations

A. Environment Division - SELECT and ASSIGN
B. Procedure Division - FD and Record definition
C. Procedure Division - OPEN/CLOSE, READ/WRITE
D. File Status

IV. Program Control and Looping Statements

A. The Family of PERFORMs
B. Conditional Statements - IF, EVALUATE
C. Statement Terminators (-END)

Days 2 - Arithmetic and Data moves

V. Data Storage

A. Character and Numeric Moves and Edit Picture Characters
B. Arithmetic statements - Add, Subtract, Multiply, Divide, Compute
C. Accessing part of a field - Redefines, Reference Modification

Days 3 - Program Language Features

VI. Program Language Features

A. Continue/Next Sentence, GOBACK, GOTO, Figurative Constants, Special Registers, INITIALIZE, STRING, 88's, SET, INSPECT, COPY,
B. Printing to a file & Headers / Trailers
C. Sub Program Access - CALL statement
D. Reading a PARM from JCL

Days 4 - Program Language Features (Continued)

F. Table Processing - Tables - SEARCH/SEARCH ALL, Intrinsic Functions, Calls to LE,
G Intrinsic Functions, Calls to LE, S0C7 Abend debugging

Days 5 - Program Language Features (Continued)

H. S0C7 Abend, Internal Data Representations - Packed/Binary

VII. Sample Program Review - DB2, CICS, IMS/DB, VSAM

Appendix A Programming Exercises

Appendix B JES RUN

Appendix C Error List Sample

Appendix D Internal Sort

Appendix E Abend Aid Dump Analysis

Appendix F Intrinsic Functions

Appendix G File Status Code

Appendix H Calls to Language Environment

Appendix I EBCDIC Collating Sequence

Appendix J National Feature Demo Program

Appendix K Two Dimensional tables

Appendix L Sub Program

Appendix M Unstring

Appendix Z 2Assembler vs COBOL features

Appendix N Sample Program - CICS

Appendix O Sample Program - DB2

Appendix P Sample Program - IMS Database

Appendix Q Compiler Options & Directing stmts

Appendix R Sample Program - VSAM

Appendix S COPY Replacing

Appendix T S0C7 Abend - IBM Fault Analyzer

Appendix U Other IF Examples

Appendix V Numeric Internal Representation

Appendix X Debug Mode

Appendix W Hex Study Program & Displays

Appendix Y References - Tables of Contents

Appendix Z Call By Content, By Reference