A set of instructions is provided for the logical
as eight-bit bytes. In a few cases the left or right four
bits of a byte are treated separately or operands are
shifted a bit at a time. The operands are either in
storage or in the general register.
introduced from the instruction stream.
Processing of data in storage proceeds left to right
the general registers, the processing, as a rule,
Except: for the editing instructions, data are not
treated as numbers. Editing provides a transformation
from packed decimal digits to alphanumeric
The set of logical operations includes moving,
and shift operations. All logical operations other than
editing are part of the standard instruction set.
The condition code is set as a result of all logical
comparing, connecting, testing, and editing operations.
Data reside in general registers or in storage or are
introduced from the instruction stream. The data size
may be a single or double word, a single character, or
variable in length. When two operands participate
they have equal length, except in the editing
Data in general registers normally occupy all 32 bits.
Bits are treated uniformly, and no distinction is made
between sign and numeric bits. In a few operations,
only the low-order eight bits of a register participate,
leaving the remaining 24 bits unchanged. In some
shift operations, 64 bits of an even/odd pair of
a general register. The high-order eight bits of the
register are made zero.
In storage-to-register operations, the storage data
occupy either a word of 32 bits or a byte of eight bits.
The word must be located on word boundaries, that
is, its address must have the two low-order bits zero.
Variable-Length Logical Information
In storagc-to-storage operations, data have a variable
field-length format, starting at any byte address and
continuing for up to a total of 256 bytes. Processing
is left to right.
stream into storage, as immediate data, are restricted
to an eight-bit byte.
the instruction stream, and only one byte in storage
placed in this register during these operations. The
The low-order eight bits of register 2 may be replaced
by a function byte during a translate-and-test
Editing requires a packed decimal field and
zones are recognized and generated as for decimal
The translating operations use a list of arbitrary
values. A list provides a relation between an argument
(the quantity used to reference the list) and the
function (the content of the location related to the
argument). The purpose of the translation may be to
convert data from one code to another code or to
A list is specified by an initial address -the address
designating the leftmost byte location of the list. The
byte from the operand to be translated is the
obtained by adding the argument to the low-order po-