- 您现在的位置：买卖IC网 > PDF目录69373 > ST72671N4B1/XXX (STMICROELECTRONICS) 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP56 PDF资料下载
参数资料
| 型号： | ST72671N4B1/XXX |
| 厂商： | STMICROELECTRONICS |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDIP56 |
| 封装： | 0.600 INCH, SHRINK, PLASTIC, DIP-56 |
| 文件页数： | 7/101页 |
| 文件大小： | 608K |
| 代理商： | ST72671N4B1/XXX |
第1页第2页第3页第4页第5页第6页当前第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页
13/101
ST72671
CENTRAL PROCESSING UNIT(Cont’d)
Stack Pointer (SP)
Read/Write
Reset Value: 01 FFh
The Stack Pointer is a 16-bit register which is al-
ways pointing to the next free location in the stack.
It is then decremented after data has been pushed
onto the stack and incremented before data is
popped from the stack (see Figure 6).
Since the stack is 256 bytes deep, the most signif-
icant byte is forced by hardware. Following an
MCU Reset, or after a Reset Stack Pointer instruc-
tion (RSP), the Stack Pointer contains its reset val-
ue (the SP7 to SP0 bits are set) which is the stack
higher address.
The least significant byte of the Stack Pointer can
be directly accessed by a LD instruction.
Note: When the lower limit is exceeded, the Stack
Pointer wraps around to the stack upper limit, with-
out indicating the stack overflow. The previously
stored information is then overwritten and there-
fore lost. The stack also wraps in case of an under-
flow.
The stack is used to save the return address dur-
ing a subroutine call and the CPU context during
an interrupt. The user may also directly manipulate
the stack by means of the PUSH and POP instruc-
tions. In the case of an interrupt, the PCL is stored
at the first location pointed to by the SP. Then the
other registers are stored in the next locations as
shown in Figure 6.
– When an interrupt is received, the SP is decre-
mented and the context is pushed on the stack.
– On return from interrupt, the SP is incremented
and the context is popped from the stack.
A subroutine call occupies two locations and an in-
terrupt five locations in the stack area.
Figure 6. Stack Manipulation Example
15
8
0
00
0
001
70
SP7
SP6
SP5
SP4
SP3
SP2
SP1
SP0
PCH
PCL
SP
PCH
PCL
SP
PCL
PCH
X
A
CC
PCH
PCL
SP
PCL
PCH
X
A
CC
PCH
PCL
SP
PCL
PCH
X
A
CC
PCH
PCL
SP
Y
CALL
Subroutine
Interrupt
event
PUSH Y
POP Y
IRET
RET
or RSP
@ 01FFh
@ 0100h
Stack Higher Address = 01FFh
Stack Lower Address = 0100h
相关PDF资料 |
PDF描述 |
|---|---|
| ST7FL19F1MATRE | 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PDSO20 |
| ST7FL34F2MCE | 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PDSO20 |
| ST7FL38F2MAE | 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PDSO20 |
| ST7FL35F2UCRE | 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, QCC20 |
| ST7FL38F2MAXE | 8-BIT, FLASH, 8 MHz, MICROCONTROLLER, PDSO20 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ST7267C8T1L | 制造商:STMicroelectronics 功能描述: |
| ST72681/R12 | 制造商:STMicroelectronics 功能描述:CONTROLLER FOR HIGH-PERFORMANCE BUS-POWERED USB 2.0 FLASH DR - Trays |
| ST72681/S13 | 制造商:STMicroelectronics 功能描述:CONTROLLER FOR HIGH-PERFORMANCE - Trays |
| ST7271 | 制造商:Panasonic Industrial Company 功能描述:IC |
| ST7271N5B1-CLF | 制造商:STMicroelectronics 功能描述: |
发布紧急采购，3分钟左右您将得到回复。