Cray CRAY-1 - Memory Transfer Format; Format for Immediate Constant Instructions

two-parcel form, the j, k, and m fields are combined to give a 22-bit
quantity.
In either form, a 7-bit operation code (gh) and a 3-bit
result field designating a result register precede the immediate constant.
Figure
4-4 illustrates the instruction format for immediate constant
instructions.
r
OPERATION
CODE
J
j k
6
RESULT CONST ANT
REG.
16 BITS
CONSTANT --.A
m
f
OPERATION
CODE
22
32 BITS
CONSTANT --.A
CONST ANT ---- S
RESULT CONSTANT
REG.
Figure 4-4. Format for immediate constant instructions
MEMORY TRANSFER FORMAT
Instructions that transfer data between the A or S registers and memory
require a 32-bit format. For these instructions, a 4-bit operation code
(g) is followed by two 3-bit fields and a 22-bit field. The first 3-bit
field (h) designates an index (A) regist~r.
When the h field is zero, the special value of zero is considered to be
the address index. Contents of Ah are not affected. The second 3-bit
field (i) designates a result or source register. The 22-bit field formed
by j, k, and m, specifies a memory word address. The upper two bits of
the
j field are unused. An operand range error occurs if either bit is set.
Figure 4-5 illustrates the format of memory transfer instructions.
2240004
4-3
E