Xerox 560 Reference Manual

DST DECIMAL STORE
(Byte index alignment)
If no illegal digit or sign is detected in the decimal
accumulator, DECIMAL STORE stores the low-order L bytes
of the decimal
accumulator into memory from the effec-
tive byte location to the effective byte location plus L-l.
If the decimal accumulator contains more significant in-
formation than is actually stored (i. e., at least one non-
zero digit was not stored), CC2 is set to 1; otherwise, CC2
is reset to O. If the result in memory is zero, the converted
si gn remains unchanged.
Affected: (EBL to EBL + L-l), Trap: Decimal arithmetic
CC1, CC2
(DECA) low-order bytes - EBL to EBL + L -1
Condition
code settings:
2 3 4 Result of DST
o - - Illegal digit or sign detected, instruction
aborted
0 0
-
All significant in-
1
formation stored
No illegal digit or
0
Some
significant
illegal sign detected,
informaTion nor
J
instruction completed
stored
DA
DECIMAL ADD
(Byte index alignment)
79
o 1 2
If no illegal digit or sign is detected in the effective deci-
mal operand or in the decimal accumulator, DECIMAL ADD
algebraically adds the decimal number to the contents of
the decimal accumulator. If the result in the decimal
accumulator is zero, the resulting sign is forced to the
positive form.
Overflow occurs if the sum exceeds the capacity of the
decimal accumulator (i. e., if the absolute value of the sum
is equal to or greater than 10
31
), in which case CCl is
reset to 0, CC2 is set to 1, and the instruction aborted with
the previous
contents of the decimal accumulator, CC3
and CC4 unchanged.
Affected: (DECA), CC
Trap: Decimal
arithmetic
(DECA) + EDO - DECA
Condition code settings:
2
3
0
0
0 0 0
0 0 0
0 0
DS
4
Result in
DECA
-
Illegal digit or
I
si gn detected
Instruction aborted
Overflow
0
Zero
No illegal digit or sign
Negative
detected, no overflow,
instruction
completed
0
Positive
DECIMAL
SUBTRACT
(Byte index alignment)
If no illegal digit or sign is detected in the effective deci-
mal operand or in the decimal accumulator, DECIMAL
SUBTRACT algebraically subtracts the decimal number from
the
contents of the decimal accumulator, and then loads
the difference into the decimal accumulator. If the result
in
the decimal accumulator is zero, the resulting sign is
forced to the positive form.
Overflow occurs if the difference exceeds the capacity of
the decimal accumulator (i. e., if the absolute value of the
difference is equal to or greater than 10
31
), in which case
CCl is reset to 0, CC2 is set to 1, and the instruction is
aborted with the contents of the previous decimal accumu-
lator, CC3 and CC4 unchanged.
Affected: (DECA), CC Trap: Decimal arithmetic
(DECA) - EDO -DECA
Condition code settings:
o
0
0
0
2 3 4 Result in DECA
o
0 0
0 0
0
- Illegal digit or )
si gn detected
- Overflow
Instruction
aborted
0 Zero
No illegal digit or sign
Negative detected, no overflow,
instruction
completed
0
Positive
Decimal Instructions
83

Xerox 560 Specifications

General

Brand	Xerox
Model	560
Category	Printer
Language	English