RR format

The operand fields of RR-format instructions designate two registers, with the following exceptions:

*--------*----*----*
|Op Code | R1 | R2 |
*--------*----*----*
0         8   12  15

Symbols used to represent registers in RR-format instructions (see INDEX and REG2 in the instruction labeled ALPHA2 below) are assumed to be equated to absolute values between 0 and 15.

Symbols used to represent immediate values in SVC instructions (see TEN in the instruction labeled DELTA2 below) are assumed to be equated to absolute values between 0 and 255.

Examples:

ALPHA1   LR              1,2
ALPHA2   LR              INDEX,REG2
GAMMA1   BCR             8,12
DELTA1   SVC             200
DELTA2   SVC             TEN

When assembled, the object code of the instruction labeled ALPHA1, in hexadecimal, is:

1812

where:

18
is the operation code
1
is register R1
2
is register R2

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