pic16f526 PORTB GPIO init problem

[goran_86]

I work on a project with PIC16F526.
I have a problem with PORTB initialization.
A part of code is presented below

;---------------------------------------------------------------------------------------
;CPU initialization
;---------------------------------------------------------------------------------------
CPU_init macro
;---------------------------------------------------------------------------------------
;clear RAM location (10h-1Fh) using indirect adressing
movlw 0x10 ;initialize pointer
movwf FSR ;to RAM
Next
clrf INDF ;clear INDF register
incf FSR, f ;increment pointer
btfsc FSR, 4 ;all done?
goto Next ;clear 1Fh-10h=Fh=15
;---------------------------------------------------------------------------------------
bcf STATUS, PA0 ;select Page0(000h-1FFh)

bcf ADCON0, ADON ;ADC module is shut-off
bcf CM1CON0, C1ON ;Comparator1 is off
bcf CM2CON0, C2ON ;Comparator2 is off

movlw 0x3F
tris PORTB

movlw 0x11
tris PORTC

endm


This is my config line:

__CONFIG _CPDF_OFF&_MCLRE_OFF&_CP_OFF&_WDTE_OFF&_IOSCFS_4MHz&_IntRC_OSC_RB4

This is my main

org 0x35
main
PowerOn

CPU_init

...........
...........
...........


When I init PORTB, 4 and PORTB, 5 as input or output (with config _IntRC_OSC_RB4) it does not work as input or output, but when I do this (_IntRC_OSC_CLKOUT) it works as clock output signal on pin RB4.
The same problem is with all PORTB pins. PORTC pins work fine.

Thank you for your help.

Goran

 

[rajtech]

Hi,

Disable portB pullups, then try.