HLASM Language Reference

Examples of Coded Machine Instructions
SI Format
The operand fields of SI-format instructions designate immediate data and a virtual
storage address.
┌────────┬─────────┬────┬────────────┐
│Op Code │ I │ B │ D │
└────────┴─────────┴────┴────────────┘
8 16 2 31
Symbols used to represent immediate data (see HEX4 and TEN in the instructions
labeled ALPHA2 and BETA1 below) are assumed to be equated to absolute values
between 0 and 255.
Symbols used to represent implicit addresses (see IMPLICIT and KEY in the
instructions labeled BETA1 and BETA2) can be either relocatable or absolute.
Symbols used to represent displacements (see DISPL4 in the instruction labeled
ALPHA2 below) in explicit addresses are assumed to be equated to absolute values
between 0 and 4095.
Examples:
ALPHA1 CLI 4(9),X'4'
ALPHA2 CLI DISPL4(NINE),HEX4
BETA1 CLI IMPLICIT,TEN
BETA2 CLI KEY,C'E'
When assembled, the object code for the instruction labeled ALPHA1, in
hexadecimal, is:
954928
where
95 is the operation code.
4 is the immediate data.
9 is the base register.
28 is the displacement from the base register
SS Format
The operand fields and subfields of SS-format instructions designate two virtual
storage addresses (coded as implicit addresses or explicit addresses) and,
optionally, the explicit data lengths you want to include. However, note that, in the
Shift and Round Decimal (SRP) instruction, a 4-bit immediate data field (see 3 in
SRP instruction below), with a value between 0 and 9, is specified as a third
operand.
Chapter 4. Machine Instruction Statements 97