btfss這個指令的第二個參數，只能接長度為3個bit的常數，不能接變數。

所以，實際上，您的指令：

btfss Number, Count

其中的Count，會被譯成Count這個變數的位址，且只抓最低位的3個bit：它是一個定值。假設說它的值是5好了，那麼，您的指令每次都會檢查Number這個變數的bit 5。如果Number 的bit 5皆為0，當然每次都會跳到Out_0囉！

請問版上個位高手~~~
假設有一程式片段如下:

movlw 0xAA
movwf Number
movlw 0x07
movwf Count

Start:
btfss Number,Count
bra Out_0
bra Out_1

Continue:
decf Count
bra Start

Out_0:
bcf PORTD,0
bra Continue
Out_1:
bsf PORTD,0
bra Continue

為何每次執行均會跑到Out_0???
這是什麼樣的問題???
謝謝~~~

我用P16F877的ICD 到PROGRAM 都有燒進去沒問體 但是每次要跑就醫職 ERROR PERFORMING REQUESTED OPERAION 然後我想說不能跑 那來個RESET吧 他就不會回去000 一直給我跑去00FF 真是快氣瘋了 我程式試用ICD說明書上那個TUT877
.ASM 有沒有辦法試看看PIC 有沒有掛掉阿 ~

請問各位大大Microchip Ic 中那一顆IC有支援RS-232通訊界面
三個急用

謝謝您的提示...

已經在美國網站下載相關資料...

PIC18F4550 可以先試一下啦

資料夾路徑太長
換個地方吧
Example:

D:\100 answer\

笨鴨我 ,有個地方不了 ??????
煩請大哥能解惑囉!!! 謝謝啦 !!!!
那就是這麼個指令 讓笨鴨我左思右不解

-------> btfsc STATUS,2 <-----------------
2 又表示甚麼呢 ????


全文如下---->

; File Name:PIC10F206_04.asm, by John Massa, Nov 20, 2004, Ver 1.00
; Description: Press the pushbutton and the LED will pulsate on and off.
LIST
; P10F206.INC Standard Header File, Version 1.01 Microchip Technology, Inc.
NOLIST
#include <p10F206.inc> ; processor specific variables
; Configure: Controls the reset pin, code protect, oscillator selection, WDT.
__CONFIG _MCLRE_OFF & _CP_OFF & _WDT_OFF
;-----[Defines & Variable Assignments]---------------------------------------
cblock 0x08
COUNT ; Count buffer
COUNT1 ; Count buffer #1
PWM_BUF ; PWM buffer
endc
;-----[Reset Vector]---------------------------------------------------------
ORG 0x000 ; PIC goes here (Origin of code) after reset.
movwf OSCCAL ; Load the oscillator calibration factor.
goto init ; go to initialization routine
;-----[Initialization]-------------------------------------------------------
init
;-----[OPTION]---------------------------------------------------------------
; OPTION register controls wake on GP0,1,3 change, GP0,1,3 pull-ups, TM0, etc
movlw b'10000111' ; Set pull-ups only, max pre-scaler
OPTION ;
;-----[CMCON0]---------------------------------------------------------------
; Comparator control register
movlw b'10001111' ; Turn-off the comparator, enable the I/O pins.
movwf CMCON0
;-----[TRIS]-----------------------------------------------------------------
; TRIS (reg#) tri-state I/O register. All I/O pins default to inputs at reset.
movlw b'00001000' ; Set GPIO pin 3 to an input, pins 0 - 3 to outputs.
TRIS GPIO ; Register 06h
;-----[Main routine]---------------------------------------------------------
main ; Routine pulsates an LED connected to GP0 thru 220 Ohms
btfsc GPIO,3 ; Press the pushbutton to begin
goto main ; ...Loop, if the pushbutton is not pressed

clrf COUNT ; The reg COUNT causes the subroutine to loop 255 times.
clrf COUNT1 ; The reg COUNT1 sets the PWM value
clrf PWM_BUF ; The reg PWM_BUF holds the PWM ratio of 'on' to 'off'
bcf GPIO,0 ; Start with the LED turned off
main1
movf COUNT1,W ; Transfer the value in reg COUNT1 to reg PWM_BUF
movwf PWM_BUF
call pwm
incfsz COUNT1,F ; Has COUNT1 counted from 0 to 255?
goto main1 ; ...No, loop again
main2
decf COUNT1,F ; ...Yes, and now COUNT1 holds the decrementing PWM value
main3
movf COUNT1,W ; Transfer the value in reg COUNT1 to reg PWM_BUF
movwf PWM_BUF
call pwm
decfsz COUNT1,F ; Has COUNT1 counted from 255 to 0?
goto main3 ; ...No, loop again
goto main ; ...Yes, start over.
;-----[Subroutines]----------------------------------------------------------
pwm ; This subroutine performs pulse width modulation.
movlw 0xFF ; Move the literal count of 255 to reg 'W'
movwf COUNT ; ...then store it in the register 'COUNT'
pwm1
movf PWM_BUF,F ; Test if the register PWM_BUF is zero
btfsc STATUS,2 ; ...Is PWM_BUF = 0?
goto led_off ; ...No, not yet, skip this instruction for now.
led_on
bsf GPIO,0 ; ...Yes, set GPIO pin-1 high, turn-on the LED
decf PWM_BUF,F ; Decrement the register PWM_BUF
goto exit
led_off
bcf GPIO,0 ; Set GPIO pin-1 low, turn-off the LED
nop
goto exit ;
exit
decfsz COUNT,F ; Has this sobroutine looped 255 times?
goto pwm1 ; ...No, keep looping
retlw 0 ; ...yes, return to the calling program

END ; Directive to end the program

3Q ,,, lar !
笨鴨我 查看 I/O port and wake up from sleep 的細節是有提到 Right before entering SLEEP,read the input pins.

那就是去睡覺前還要做 一件事....

-----> MOVF GPIO,W <------

對吧 ??? 哈...哈... 了解......

不知道在 C 裡面加入Asm 後,變數如何宣告使用?