I test the following and it works perfectly (an led flasher)
(more below)
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#include "P16F84.INC"           ; Include header file

        LIST P=16F84, R=DEC     ; Use the PIC16F84 and decimal system

        __config  _XT_OSC & _WDT_OFF & _PWRTE_ON

        ; Use Crystal clock, Watch dog off, Power up timer on (changed to RC for
now!)
        ; For other oscillators change XT to LS,HS or RC.

        cblock 0x20     ; Declare variable addresses, start at 0x20
                Counter,Loop1,Loop2
        endc

                ORG     0               ; This tells the assembler where
                GOTO    Start           ; to put the first instruction.

; decalaration of the delay subroutine
; - the delay loop is implemented as a for loop sort of routine
Delay           MOVLW   250
                MOVWF   Loop1
Outer           MOVLW   110
                MOVWF   Loop2
Inner           NOP
                NOP
                DECFSZ  Loop2,F
                GOTO    Inner
                DECFSZ  Loop1,F
                GOTO    Outer
                RETURN

; Main Loop
Start           BSF     STATUS,RP0      ; Select bank 1 (bit #RP0 from the status register)
                CLRF    TRISB           ; Select Output on all PORTB bits
                BCF     STATUS,RP0      ; Select bank 0
                CLRF    PORTB           ; Turn off all LEDs
                BSF     PORTB,0         ; Turn on LED0 (the first RB0)


                CLRF    Counter
                BCF     STATUS,C        ; Set carry 0
Go              MOVLW   7               ; (move 7 into the acc. [111])
                MOVWF   Counter         ; 8 LED's to light in turn (move 7 into )
Left            RLF     PORTB,F         ; Rotate Left PORTB
                CALL    Delay
                DECFSZ  Counter,F
                GOTO    Left
                MOVLW   7
                MOVWF   Counter
Right           RRF     PORTB,F         ; Last LED is on, reverse dir.
                CALL    Delay
                DECFSZ  Counter,F
                GOTO    Right
                GOTO    Go
            END

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My code,
the led on RB1 is NOT on!

The RB1 pin goes into a 1K resistor and into the led and off to the ground.

The Switch is connected to a high regularly (pulled up via 1k resistor).
Press the button and it gives short to the ground.

I have a RC oscillator in the circuit, but keep the oscillator in XT mode.
If I switch to RC mode => flasher not work.

.Sep.