Assembler Language

SUMMARY: Suitable for the BCS Mainframe Technology professional Exams for levels 1 and 2 Developer and Level 2 Engineer (z/OS)
AUDIENCE: Systems Programmers, Technical Support and Applications Programmers who need the ability to write and debug Assembler language programs and understand better the software that their installation uses.
PREREQUISITES: Delegates are expected to have some knowledge of the organisation and operation of zSeries Enterprise Servers. Some previous programming experience is necessary and knowledge of hexadecimal arithmetic would also be useful.
DURATION: 4 days. Hands on.
OBJECTIVES: The objectives of this course are to:
Develop a better understanding of the machine and how it processes instructions.
Develop the ability to read, maintain and write assembler programs, particularly those small functions which will increase corporate IT throughput.
Provide delegates with a practical introduction to the essential operating system interfaces with Assembler.
Improve skills in Diagnostics and dump analysis.
COURSE CONTENT:
Control Section
Source Code Definitions: Object Modules and Load Modules
Control Section Definitions
· START Command Definition
· CSECT Command Definition
Setting up Addressability in a Control Section
USING Statement
BASR Instruction (Branch and Save Register)
Multiple Base Register Specifications
MVC Move Character Instruction
LA Load Address Instruction
Symbolic Address
Base Addressing
Displacement Calculations
Index Addressability
MVI Move Immediate
· LITERALS
· EQUATES

Data Definitions
Define Constant
· Binary
· Characters
· Hexadecimal
· Fixed Point
· Define Storage
· Addressing

Operand subfields, length attributes, Constant alignment, padding, types, duplication factor expressions, Bit length modifier, Y CONST, A CONS, V CONS

Instruction Set
CLC Compare Logical Character
B Branch Instruction Format
CLI Compare Logical Integer
STM Storage Multiple
IC Insert Character
STC Store Character
L Load
LH Load Halfword
LR Load Register
SH Subtract Halfword
ST Store
LTR Load and Test
DSECT Dummy Section
· How to define a Dummy Section.
· What a Dummy Section is.
· How to use a Dummy Section.
Workshop: Read Card Input Until Last Card, then Output Cards

Instruction Set (continued)
MVS I/O needs
DOS I/O needs
C Compare Function
CH Compare Halfword
CR Compare Register
BCT Branch on Count
BCTR Branch on Count Register
BAL Branch and Link

Binary Conversion
PACK Pack
CVB Convert to Binary
CVD Convert to Decimal
UNPK Unpack

Binary Arithmetic
AR Add Register
A Add Instruction
AH Add Halfword
SR Subtract Register
SH Subtract Halfword
MH Multiply Halfword
M Multiply
D Divide
DR Divide Register
Workshop: Sort Data Using A Bubble Sort

Decimal Arithmetic
AP Add Decimal
CP Compare Decimal
DP Divide Decimal
ED Edit
EDMK Edit and Mark
MP Multiply Decimal
SRP Shift and Round Decimal
SP Subtract Decimal
ZAP Zero and Add
Workshop: Binary Arithmetic

Linkage Instructions
BAS/BASR Branch and Save Register
Workshop: Packed Arithmetic