Instruction Set used in simplified instructional Computer (SIC)
Last Updated :
06 Oct, 2020
Prerequisite – Simplified Instructional Computer (SIC)
These are the instructions used in programming the Simplified Instructional Computer(SIC).
Here,
A stands for Accumulator
M stands for Memory
CC stands for Condition Code
PC stands for Program Counter
RMB stands for Right Most Byte
L stands for Linkage Register
MNEMONIC |
OPERAND |
OPCODE |
EXPLANATION |
ADD |
M |
18 |
A = A + M |
AND |
M |
40 |
A = A AND M |
COMP |
M |
28 |
compares A and M |
DIV |
M |
24 |
A = A / M |
J |
M |
3C |
PC = M |
JEQ |
M |
30 |
if CC set to =, PC = M |
JGT |
M |
34 |
if CC set to >, PC = M |
JLT |
M |
38 |
if CC set to <, PC = M |
JSUB |
M |
48 |
L = PC ; PC = M |
LDA |
M |
00 |
A = M |
LDCH |
M |
50 |
A[RMB] = M[RMB] |
LDL |
M |
08 |
L = M |
LDX |
M |
04 |
X = M |
MUL |
M |
20 |
A = A * M |
OR |
M |
44 |
A = A OR M |
RD |
M |
D8 |
A[RMB] = data specified by M[RMB] |
RSUB |
|
4C |
PC = L |
STA |
M |
0C |
M = A |
STCH |
M |
54 |
M[RMB] = A[RMB] |
STL |
M |
14 |
M = L |
STSW |
M |
E8 |
M = SW |
STX |
M |
10 |
M = X |
SUB |
M |
1C |
A = A – M |
TD |
M |
E0 |
test device specified by M |
TIX |
M |
2C |
X = X + 1 ; compare X with M |
WD |
M |
DC |
device specified by M[RMB] = A[RMB] |
Like Article
Suggest improvement
Share your thoughts in the comments
Please Login to comment...