M34282E2GP MITSUBISHI [Mitsubishi Electric Semiconductor], M34282E2GP Datasheet - Page 6

• Manufacturer Part Number: M34282E2GP
• Description: SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

Fig. 4 TABP p instruction execution example
FUNCTION BLOCK OPERATIONS
CPU
(1) Arithmetic logic unit (ALU)
(2) Register A and carry flag
(3) Registers B and E
(4) Register D
6
The arithmetic logic unit ALU performs 4-bit arithmetic such
as 4-bit data addition, comparison, and bit manipulation.
Register A is a 4-bit register used for arithmetic, transfer,
exchange, and I/O operation.
Carry flag CY is a 1-bit flag that is set to “1” when there is a
carry with the AMC instruction (Figure 1).
It is unchanged with both A n instruction and AM instruction.
The value of A
instruction (Figure 2).
Carry flag CY can be set to “1” with the SC instruction and
cleared to “0” with the RC instruction.
Register B is a 4-bit register used for temporary storage of 4-
bit data, and for 8-bit data transfer together with register A.
Register E is an 8-bit register. It can be used for 8-bit data
transfer with register B used as the high-order 4 bits and
register A as the low-order 4 bits (Figure 3).
Register D is a 3-bit register.
It is used to store a 7-bit ROM address together with register
A and is used as a pointer within the specified page when the
TABP p, BLA p, or BMLA p instruction is executed (Figure 4).
Immediate field
TABP p instruction
p
3
value p
p
PC
2
0
p
H
is stored in carry flag CY with the RAR
1
p
0
The contents
of register D
DR
2
DR
1
DR
Specifying address
0
PC
A
The contents
of register A
3
L
A
2
A
1
A
URSC instruction
MITSUBISHI
ELECTRIC
0
URS flag (1)
Most significant 1 bit
Fig. 2 RAR instruction execution example
Fig. 3 Registers A, B and register E
Fig. 1 AMC instruction execution example
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Register E
Middle-order 4 bits
SC instruction
ROM
4
<Set>
Register B
Register B
(M(DP))
B
B
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
Low-order 4 bits
3
3
(CY)
(A)
ER
B
B
2
2
7
0
ER
B
CY
B
A
1
1
MITSUBISHI MICROCOMPUTERS
Addition
0
6
ER
TEAB instruction
TABE instruction
B
RC instruction
TAB instruction
B
TBA instruction
0
0
5
Carry flag CY (1)
<Clear>
Register B (4)
ER
Register A (4)
CY A
A
4
3
ER
A
3
ALU
2
3
ER
RAR instruction
A
A
A
A
<Result>
3
3
<Rotation>
<Carry>
2
1
2
4282 Group
ER
A
A
A
A
Register A
Register A
2
2
1
0
1
ER
A
A
1
1
0
A
A
0
0