Course Description

OS/390 Assembler Language: Classic

This course: course objectives; course outline;
Assembler curriculum; Topic list; Course list; Home page

Benefits

Students who complete this course will be able to write or maintain basic Assembler programs. The emphasis is on learning all the hardware instructions used by applications programmers as well as learning the basic interfaces to MVS or OS/390 from Assembler language programs.

Audience

Experienced programmers needing to learn Assembler as an additional language or who need a refresher in Assembler. This course may also be used to teach Assembler as a first language, but it should probably be extended to seven days.

Prerequisites

At the very least the student entering this course should have background in using ISPF/PDF or similar product used for creating programs and submitting jobs. Some experience in writing programs in a third generation language such as COBOL, PL/I, FORTRAN, or C.

Related IBM Materials

This course is drawn from these IBM manuals; access to them in the classroom is required (via hardcopy, BookManager, etc.):

SA22-7201 - Principles of Operation
GX20-0406 - Reference Summary (supplied
                   with the course)
SC26-4940 - High Level Assembler reference

• Hardware fundamentals (registers, memory, addressing)
• Machine instructions
• The Assembler
• Data formats (character, packed decimal, binary)
• Working with files and program linkages
• Calculations: rounding, editing, planning results (significant digits, implied decimal positions)
• Loops and tables
• Multiple base registers
• DSECTs, ORG, and EQU

Exercises

There are 14 hands-on exercises

Notes

1. This course covers the Assembler and the application-programmer oriented hardware instructions that have been available from the introduction of the S/360 and that were added over the first 20 years or so of the architecture. It is estimated that 90% of existing Assembler applications use only the instructions covered in this course.

2. We do not cover any instructions in these categories: floating point, vector, privileged, semi-privileged.

3. The course integrates the latest features of the High Level Assembler (HLASM).

4. The follow on courses are "z/OS Assembler: Basic Interfaces", "Assembler Language: Update",  and "z/OS Assembler for Application Programmers".