The 16f84's datasheet say "don't use the tris instruction anymore" The TRIS register is a standard register in the 16f84. You can write or read it as any other register. The TRIS A is located at 85h, the same address than the port and the TRISB is at 86h. You need to select the bank 1 and write directly to the register. The suggested mode is: TRIS_A equ 0x85 TRIS_B equ 0x86 bsf status, rpo ; select bank 1 movlw 0x1f movwf TRIS_A movlw 0 movwf TRIS_B bcf status, rpo Atte: Pablo De Leon pdeleon@bigfoot.com >Try to do like this. >bsf STATUS,RP0 >movlw 0x1F >tris PORTA >movlw 0x00 >tris PORTB >bcf STATUS,RP0 > >I think the initialization of its PORTS not this correct one. You have to >operate in bank1 >Good Luck. > >-----Mensagem original----- >De: Tony Nixon >Para: PICLIST@MITVMA.MIT.EDU >Data: Domingo, 16 de Maio de 1999 16:08 >Assunto: Re: WHAT'S WRONG? [MIGUEL] > > >WF AUTOMACAO wrote: >> >> Dear old friends, help me! >> >> ; Inicio >> list p=16F84 >> radix dec >> include >> ; Variables >> contador equ d'12' >> org 0x000 >> movlw 0x1F >> tris PORTA >> movlw 0x00 >> tris PORTB >> >> movlw 0 >> movwf contador >> >> loop >> incf contador,f >> >> movlw contador <<<<<<<<<< MOVF CONTADOR,W >> movwf PORTB >> >> goto loop >> >> END >> >> Why don't my PORTB pulse? (The level is constant in all BITS of PORTB... >;( ) >> >> Can you see what i'm doing wrong? >> >> Thanks! >> >> Miguel > >-- >Best regards > >Tony > >PicNPoke - Multimedia 16F84 Beginners PIC Tools. > >http://www.picnpoke.com >Email picnpoke@cdi.com.au > >