Control Data 3100 Reference Manual page 79

Rev. B
23 18 17 16 1 5 14
21
I
a
I
b
m
a
=
addressing mode designator
b
=
index register designator
00
m
=
storage address: M
=
m + (8
b
)
(Approximate execution time: 3.5
jlsec.)
Instruction Description: Load
Q
with a 24-bit quantity from storage address M.
Comments: Indirect addressing and address modification may be used.
23 18 17 16
00
23
\16 020100l
I
00000-77777
I
0-3
I
'~----~y------/~
word address character
designator
If b
=
1, r is modified by
index register 8
2 :
R
=
r+ (8
2 ).
If b
=
0, r is not modified (r
=
R).
NOTE
(Approximate execution time: 3.5
jlsec.)
Since the sign of Bb is extended during character address modification, it is possible
to only reference with ± 16,38310 characters.
Instruction Description: Load bits 00 through 05 of
Q
with the character from storage
specified by character address R. The
Q
register is cleared prior to the load operation.
Comments: Indirect addressing may not be used. Characters are specified in storage as
follows:
23 18 17
12 11 06 05 00
o
I
2 3
'"
, /
~
character designators
23 18 17 16 15 14
54
I
a
I
b
m
a
=
addressing mode designator
b
=
index register designator
00
m
=
storage address (indexing not permitted)
(Approximate execution time: 3.8 jlsec.)
Instruction Description: Load the specified index register, Bb, with the lower 15 bits of the
operand stored at address m.
Comments: Indirect addressing may be used but address modification is not possible. During
indirect addressing only a and m are inspected. Symbol b from the initial instruction speci-
fies which index register is to be loaded with the lower 15-bits from the storage address.
7-22