參數(shù)資料
型號: M38B41MEH-XXXXFP
廠商: Mitsubishi Electric Corporation
英文描述: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
中文描述: 單芯片8位CMOS微機
文件頁數(shù): 9/78頁
文件大?。?/td> 1214K
代理商: M38B41MEH-XXXXFP
9
38B4 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
[Processor Status Register (PS)]
The processor status register is an 8-bit register consisting of 5
flags which indicate the status of the processor after an arithmetic
operation and 3 flags which decide MCU operation. Branch opera-
tions can be performed by testing the Carry (C) flag , Zero (Z) flag,
Overflow (V) flag, or the Negative (N) flag. In decimal mode, the Z,
V, N flags are not valid.
Bit 0: Carry flag (C)
The C flag contains a carry or borrow generated by the arithmetic
logic unit (ALU) immediately after an arithmetic operation. It can
also be changed by a shift or rotate instruction.
Bit 1: Zero flag (Z)
The Z flag is set if the result of an immediate arithmetic operation
or a data transfer is “0”, and cleared if the result is anything other
than “0”.
Bit 2: Interrupt disable flag (I)
The I flag disables all interrupts except for the interrupt
generated by the BRK instruction.
Interrupts are disabled when the I flag is “1”.
Bit 3: Decimal mode flag (D)
The D flag determines whether additions and subtractions are
executed in binary or decimal. Binary arithmetic is executed when
this flag is “0”; decimal arithmetic is executed when it is “1”.
Decimal correction is automatic in decimal mode. Only the ADC
and SBC instructions can be used for decimal arithmetic.
Bit 4: Break flag (B)
The B flag is used to indicate that the current interrupt was
generated by the BRK instruction. The BRK flag in the processor
status register is always “0”. When the BRK instruction is used to
generate an interrupt, the processor status register is pushed
onto the stack with the break flag set to “1”.
Bit 5: Index X mode flag (T)
When the T flag is “0”, arithmetic operations are performed
between accumulator and memory. When the T flag is “1”, direct
arithmetic operations and direct data transfers are enabled
between memory locations.
Bit 6: Overflow flag (V)
The V flag is used during the addition or subtraction of one byte
of signed data. It is set if the result exceeds +127 to -128. When
the BIT instruction is executed, bit 6 of the memory location
operated on by the BIT instruction is stored in the overflow flag.
Bit 7: Negative flag (N)
The N flag is set if the result of an arithmetic operation or data
transfer is negative. When the BIT instruction is executed, bit 7 of
the memory location operated on by the BIT instruction is stored
in the negative flag.
Table 5 Set and clear instructions of each bit of processor status register
Set instruction
Clear instruction
C flag
Z flag
_
_
I flag
D flag
B flag
_
_
T flag
V flag
_
N flag
_
_
SEC
CLC
SEI
CLI
SED
CLD
SET
CLT
CLV
相關(guān)PDF資料
PDF描述
M38B42MEH-XXXXFP SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B43MEH-XXXXFP SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B44MEH-XXXXFP SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B45MEH-XXXXFP SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B46MEH-XXXXFP SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
M38B41MFH-XXXXFP 制造商:MITSUBISHI 制造商全稱:Mitsubishi Electric Semiconductor 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B42E1H-XXXXFP 制造商:MITSUBISHI 制造商全稱:Mitsubishi Electric Semiconductor 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B42E2H-XXXXFP 制造商:MITSUBISHI 制造商全稱:Mitsubishi Electric Semiconductor 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B42E3H-XXXXFP 制造商:MITSUBISHI 制造商全稱:Mitsubishi Electric Semiconductor 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
M38B42E4H-XXXXFP 制造商:MITSUBISHI 制造商全稱:Mitsubishi Electric Semiconductor 功能描述:SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER