Proteus w/ PIC18F458中的堆栈溢出

Question

我使用的是一个PIC18F4580模块，我想模拟我用Proteus在MPLAB上写的一个发光二极管，但是我一直得到以下信息：

[PIC18 STACK] PC=0x000E. Stack overflow is forcing device reset. [U1]

我的MPLAB代码：

;Complete the schematic below showing how to connect on a PIC:
;(a) a pushbutton PB to RD4, so that the RD4=0 (LOW) when the pushbutton is pressed,
;and 1 (HIGH) when the pushbutton is released,
;(b) a LED1 to RC1, so that the LED1 is ON when RC1=0 (LOW) and OFF when RC1=1
;(HIGH),
;(c) a LED2 to RC2, so that the LED2 is ON when RC2=1 (HIGH) and OFF when RC2=0
;(LOW).
;Assume that bit RD4 is an input and represents the condition of a door alarm.
   ; If it goes LOW, it
;means that the door is open
   ;Monitor the pushbutton continuously. Whenever it goes LOW, 
  ; send a HIGH-to-LOW pulse
;eighty times to the LED1, then turn off LED1 and turn on LED2. Otherwise, turn on this LED1
;and turn off LED2.

   PORTD EQU 0xF83
   PORTC EQU 0xF82
   TRISC EQU 0xF94
   TRISD EQU 0xF95
   Counter EQU 0x20
 ;LED 1 > RC1 ON: 0 OFF: 1
 ;LED 2 > RC2 ON: 1 OFF: 0
 
   BSF TRISD, 4
   BCF TRISC, 1
   BCF TRISC, 2
   
   LoopPB1:
    MOVLW D'80'
    MOVWF Counter
    Call PB1
    DECFSZ Counter
    Call LoopPB1
    BSF PORTC, 1
    BSF PORTC, 2
    return
   
   PB1:
    BCF PORTC, 1 ;S
    BCF PORTC, 1
    return
   
   BTFSS PORTD, 4
   BCF PORTC,1
   BRA PB1
   RETURN
   
    END

变形杆菌原理图：原理图

这是我第一次与MPLAB和Proteus合作。

编辑:我的代码现在一直打开发光二极管，直到按下按钮才能关闭它，但是我没有看到对LED1的80次高到低的调用，而且，LED2似乎没有打开任何东西。

经修订的守则：

    ORG 0
    
    
;Complete the schematic below showing how to connect on a PIC:
;(a) a pushbutton PB to RD4, so that the RD4=0 (LOW) when the pushbutton is pressed,
;and 1 (HIGH) when the pushbutton is released,
;(b) a LED1 to RC1, so that the LED1 is ON when RC1=0 (LOW) and OFF when RC1=1
;(HIGH),
;(c) a LED2 to RC2, so that the LED2 is ON when RC2=1 (HIGH) and OFF when RC2=0
;(LOW).
;Assume that bit RD4 is an input and represents the condition of a door alarm.
   ; If it goes LOW, it
;means that the door is open
   ;Monitor the pushbutton continuously. Whenever it goes LOW, 
  ; send a HIGH-to-LOW pulse
;eighty times to the LED1, then turn off LED1 and turn on LED2. Otherwise, turn on this LED1
;and turn off LED2.

   PORTD EQU 0xF83
   PORTC EQU 0xF82
   TRISC EQU 0xF94
   TRISD EQU 0xF95
   Counter EQU 0x20
 ;LED 1 > RC1 ON: 0 OFF: 1
 ;LED 2 > RC2 ON: 1 OFF: 0
 
   BSF TRISD, 4
   BCF TRISC, 1
   BCF TRISC, 2
   
      ;Monitor the pushbutton continuously. Whenever it goes LOW, 
  ; send a HIGH-to-LOW pulse
;eighty times to the LED1, then turn off LED1 and turn on LED2. Otherwise, turn on this LED1
;and turn off LED2.
   MOVLW D'80'
   MOVWF Counter
   
   
   
   LoopPB1:
    MOVLW D'80'
    MOVWF Counter
    Loopn:
    BSF PORTC, 1 ;S
    BCF PORTC, 1
    DECFSZ Counter, F
    BRA Loopn
    BSF PORTC, 2
    BSF PORTC, 1
    BRA Check
    
   
   
   Check:
   BTFSS PORTD, 4
   BRA Check
   BRA LoopPB1
    
    END

更新示意图：在这里输入图像描述

Answer 1

stacko verflow问题似乎是由这一行引起的：

Call LoopPB1

您可以递归地调用LoopPB1 80次，但是PIC18设备没有适合递归操作的硬件。它们有32个深硬件调用堆栈，因此，当第33次调用LoopPB1时，硬件堆栈只会溢出。无论何时执行递归调用或嵌套调用，硬件都会自动将返回地址推送到堆栈上。因此，您只能在应用程序中执行32个嵌套或递归调用。

必须按以下方式更改该行，以避免递归调用和堆栈溢出：

BRA LoopPB1

BRA指令是循环的正确指令，不会导致硬件堆栈溢出，因为它不需要存储返回地址。

注意，下面的代码在程序流中也是不可实现的：

BTFSS PORTD, 4
   BCF PORTC,1
   BRA PB1
   RETURN

作为附带说明，除了上面提到的问题之外，您的代码似乎没有执行作业中所要求的功能。