參數(shù)資料
型號: Q67121C2168A1
英文描述: IC-SM-16 BIT CPU
中文描述: 集成電路的Sm - 16位CPU
文件頁數(shù): 46/121頁
文件大小: 1000K
代理商: Q67121C2168A1
Semiconductor Group
6-12
On-Chip Peripheral Components
C501
The reason why read-modify-write instructions are directed to the latch rather than the pin is to avoid
a possible misinterpretation of the voltage level at the pin. For example, a port bit might be used to
drive the base of a transistor. When a “1” is written to the bit, the transistor is turned on. If the CPU
then reads the same port bit at the pin rather than the latch, it will read the base voltage of the
transistor (approx. 0.7 V, i.e. a logic low level!) and interpret it as “0”. For example, when modifying
a port bit by a SETB or CLR instruction, another bit in this port with the above mentioned
configuration might be changed if the value read from the pin were written back to the latch.
However, reading the latch rater than the pin will return the correct value of “1”.
Table 6-5
Read-Modify-Write"- Instructions
Instruction
Function
ANL
Logic AND; e.g. ANL P1, A
ORL
Logic OR; e.g. ORL P2, A
XRL
Logic exclusive OR; e.g. XRL P3, A
JBC
Jump if bit is set and clear bit; e.g. JBC P1.1, LABEL
CPL
Complement bit; e.g. CPL P3.0
INC
Increment byte; e.g. INC P1
DEC
Decrement byte; e.g. DEC P1
DJNZ
Decrement and jump if not zero; e.g. DJNZ P3, LABEL
MOV Px.y,C
Move carry bit to bit y of port x
CLR Px.y
Clear bit y of port x
SETB Px.y
Set bit y of port x
相關(guān)PDF資料
PDF描述
Q67121C452 IC-SM-8-BIT CPU-12MHZ
Q67126-C2088 RF inductor, ceramic core, 2% tol, SMT, RoHS
Q67127-C2036SAB-C161R1-L16M IC-SM-16 BIT CPU
Q67120-C2200 16-Bit Single-Chip Microcontroller Bare Die Delivery
Q67120-C1054 High Speed CMOS Logic Triple 3-Input NOR Gates 14-SOIC -55 to 125
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
Q67121C452 制造商:未知廠家 制造商全稱:未知廠家 功能描述:IC-SM-8-BIT CPU-12MHZ
Q67121-C848 制造商:INFINEON 制造商全稱:Infineon Technologies AG 功能描述:16-Bit CMOS Single-Chip Microcontroller
Q67121-C862 制造商:INFINEON 制造商全稱:Infineon Technologies AG 功能描述:C16x-Family of High-Performance CMOS 16-Bit Microcontrollers
Q67121-C900 制造商:INFINEON 制造商全稱:Infineon Technologies AG 功能描述:16-Bit CMOS Single-Chip Microcontroller
Q67121-C923 制造商:INFINEON 制造商全稱:Infineon Technologies AG 功能描述:C16x-Family of High-Performance CMOS 16-Bit Microcontrollers