APPENDIX
Appendix 6. Machine instructions
7721 Group User’s Manual
17–46
Symbol
Functions
Details
IMP
IMM
A
DIR
DIR,b
DIR,X
DIR,Y
(DIR)
(DIR,X)
(DIR),Y
#
n
op
n
op n
op
n
op
Addressing modes
ACC
←M
M
←IMM
DT
←IMM
X
←M
Y
←M
m=0
0
→ b15 b0 →C
m=1
0
→ b7 b0 →C
Enters the contents of the memory into the accummulator.
Enters the immediate vaiue into the memory.
Enters the immediate value into the data bank regiater.
Enters the contents of the memory into index register X.
Enters the contents of the memory into index register Y.
Shifts the contents of the accumulator or the contents of
the memory one bit to the right. The bit 0 of the accumu-
lator or the memory is entered into the C flag. “0” is en-
tered into bit 15 (bit 7 when the m flag is “1.”)
B, A
←AVM
Mn+i
←Mm+i
Mn–i
←Mm–i
PC
←PC+1
ACC
←ACCVM
M(S)
←IMM2
S
←S–1
M(S)
←IMM1
S
←S–1
M(S)
←M((DPR)+IMM
+1)
S
←S–1
M(S)
←M((DPR)+IMM)
S
←S–1
EAR
←PC+IMM2,IMM1
M(S)
←EARH
S
←S–1
M(S)
←EARL
S
←S–1
m=0
M(S)
←AH
S
←S–1
M(S)
←AL
S
←S–1
m=1
M(S)
←AL
S
←S–1
m=0
M(S)
←BH
S
←S–1
M(S)
←BL
S
←S–1
m=1
M(S)
←BL
S
←S–1
Transmits the data block. The transmission is done from
the lower order address of the block.
Advances the program counter, but pertorms nothing else.
Logical sum per bit of the contents of the accumulator and
the contents of the memory is obtained. The result is en-
tered into the accumulator.
The 3rd and the 2nd bytes of the instruction are saved into
the stack, in this order.
Specifies 2 sequential bytes in the direct page in the 2nd
byte of the instruction, and saves the contents into the
stack.
Regards the 2nd and 3rd bytes of the instruction as 16-bit
numerals, adds them to the program counter, and saves
the result into the stack.
Saves the contents of accumulator A into the stack.
Saves the contents of accumuator B into the stack.
LDA
(Notes 1,2)
LDM
(Note 5)
LDT
LDX
(Note 2)
LDY
(Note 2)
LSR
(Note 1)
MPY
(Notes 2,11)
MVN
(Note 8)
MVP
(Note 9)
NOP
ORA
(Notes 1,2)
PEA
PEI
PER
PHA
PHB
n
op nn
op
op n
n
op
op n
25 2
B2 62
2
43
74 53
A6 42
2
A4 42
5 2
21 46 72
56 72
89
09
16 3
89
05
89
15
19 3
89
12
20 33
3
21
09 22
05
42
05
4
6
2
3
52
3
7
42
15
12 6
8
2
3
01
42
01
7
9
2
3
11
42
11
10 3
3
46 3
3
7
42
B2
3
89 3
3
10
2
42
09
Multiplies the contents of accumulator A and the contents of the memory.
The higher order of the result of operation are entered into accumulator
B, and the lower order into accumulator A.
Transmits the data block. Transmission is done form the
higher order address of the data block.
##
#
A9 22
42
A9
89
C2
53
64
42
A5
A5 4
B5
42
B5
A1
42
A1
72 B1
42
B1
8
B6 5
B4
A0
A2 2
2
4A
42
4A
2
4
89
11
22
89
01
21
18 3
EA
43
15
42
12
8