RCA 70/46 User Manual

Shift Right Single
(SRA)
General Description
Format
(RS)
Condition Code
Interrupt
Action
Notes
Fixed-Point
Instructions
• The integer portion of the operand in the general register -specified by
the first address (R
1
)
is shifted right the number of positions specified by
the second address (B
2
/D
2
). The second address is used as a count and not
to address data. The low-order six bits of the second address field constitute
the count. The remaining bits are ignored.
8A
o
7 8
11 12
15 16
19 20
31
• 0 - result is zero.
1 -
result is less than zero.
2 - result is greater than zero.
3-not used.
• None.
• 1. All 31 bit positions of the integer are shifted. The sign is not altered.
The sign bit is propagated through the positions vacated in the left
end of the operand. The bits shifted out to the right are lost.
2. Shifting to the right is equivalent to low-order truncation or division
by powers
of two.
3.
Shifts greater than 31 cause all significant bits to be lost. A zero for
positive numbers and a minus one for negative numbers is the result
of such shifts.
4. Fixed-point positive numbers go towards zero; Fixed-point negative
numbers go towards minus one.
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RCA 70/46 Specifications

General

Brand	RCA
Model	70/46
Category	Computer Hardware
Language	English