Instruction Set used in SIC/XE

Prerequisite – Instruction Set used in simplified instructional Computer (SIC)
As SIC/XE is upward compatible with respect to SIC, therefore all the instructions in SIC are also used in SIC/XE. The instructions unique to SIC/XE are:

ADDR R1, R2 90 R2 = R2 + R1
CLEAR R1 04 R1 = 0
COMPR R1, R2 A0 compares R1 and R2
DIVR R1, R2 9C R2 = R2 / R1
LDB M 68 B = M
LDS M 6C S = M
LDT M 74 T = M
MULR R1, R2 98 R2 = R2 * R1
RMO R1, R2 AC R2 = R1
SHIFTL R1, n A4 left shifts R1 n times
SHIFTR R1, n A8 right shifts R1 n times
STB M 78 M = B
STS M 7C M = S
STT M 84 M = T
SUBR R1, R2 94 R2 = R2 – R1
TIXR R1 B8 X = X + 1; compares X and R1

M stands for Memory
R1 and R2 are registers (A, B, S, T)

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