Programming a PIC16F628 microcontroller using MPLABX and PICkit3 - A Hello World Program demonstrating the basic principles of writing a piece of ASM code. The LEDs on the PORTB are lighting up according to some pressed buttons on the PORTA used as an input here.

For details about the hardware used in this video, refer to the following website: www.funelectronicstoday.com

The result code, in case you want to copy-paste it:

; Hello world basic 16F628 ASM program
 
 RESET CODE 0x00
 #INCLUDE P16F628A.inc ; put angle brackets here
 __CONFIG _HS_OSC & _CP_OFF & _LVP_OFF & _BODEN_OFF & _MCLRE_ON & _PWRTE_OFF & _WDT_OFF 
 
 ; THIS PROGRAM WAS DESIGNED FOR 20 MHZ OSC
 ;------------------------------------
 ;_XT_OSC             : EXTERNAL 4MHZ
 ;_HS_OSC             : EXTERNAL 20MHZ
 ;_INTRC_OSC_NOCLKOUT : INTERNAL 4MHZ
 ;------------------------------------
 
 CBLOCK 0X20 ; THIS IS HOW YOU DECLARE A BLOCK OF VARIABLES
    NVAR1, NVAR2
 ENDC
 
 CLRF PORTA ;SET THESE PINS BEFORE YOU ACTUALLY CONFIGURE THEM
 CLRF PORTB
 
 MOVLW 0X07    ; DISABLE THE COMPARATORS AND ENABLING THE PINS FOR
 MOVWF CMCON   ; FUNCTIONING AS I-O

 
 
 
 
 
 BCF STATUS, RP1 ;SETS BANK1
 BSF STATUS, RP0 ;
 
 MOVLW B'00111111' ;SET PINS 0 - 4 AS INPUTS ; TRIS 5 AS 1 ALWAYS  
 MOVWF TRISA 
 
 MOVLW 0X00 ;SET PINS 0 - 7 AS OUTPUTS
 MOVWF TRISB 
 
 BCF STATUS, RP1 ;SETS BANK1
 BCF STATUS, RP0 ;
 
 
;MAIN LOOP----------------

REPEAT
 
 MOVFW PORTA
 MOVWF NVAR1
 
 MOVFW NVAR1
 MOVWF PORTB
 
 GOTO REPEAT ; END OF MAIN LOOP 
 
 END