My LCD code is not working...

[kvrajasekar]

Hi,

I am using CDM16216b LCD to interface with 16f72.I am trying to display characters on lcd,but i didnt get anything on LCD.

Please kindly reply me,where i am going wrong.

list    p=16f72   		        ;PIC16f72 is the target processor
	INCLUDE "P16f72.INC" 
;------------------------------------------------------------------------------------
; PORTA control bits


	__CONFIG _PWRTE_ON & _XT_OSC & _WDT_OFF   ;  configuration switches
#DEFINE LCD_RS 	PORTA, 0            ;  RA0 is RS line of LCD
#DEFINE LCD_E  	PORTA, 1            ;  RA1 is E line of LCD
                                    ;  RC0-RC3 are D4-D7 of LCD
Temp	equ		0x20
delay1	equ		0x21

	org	0x00
	goto start

	                          
;------------------------------------------------------------------------------------
start
		bsf 	STATUS, RP0 		; Bank1 
		errorlevel 1,-302      ; Don't warn me about bank 1

		movlw 	b'00000000'			; Defining input and output pins 
		movwf 	TRISA 				; Writing to TRISA register 
		movlw 	b'00000000'			; Defining input and output pins 
		movwf	TRISB 				; Writing to TRISB register 1-input,0-output
		movlw	b'00000000'
		movwf	TRISC
		movlw   b'10000110'			; TMR0,prescaler-128
		movwf   OPTION_REG
		movlw	0x07
		movwf	ADCON1
		bcf 	STATUS, RP0 		; Bank0 
		clrf 	PORTA				; potra,portb initially set to low
		clrf	PORTB
		clrf	PORTC
		

		
		call	lcd_init
		bsf		PORTA,5				; Buzzer
		call	delay_0.5s
		bcf		PORTA,5

		call	disp_main
		movlw	0xC1
		call    disp_cmd
		btfsc	PORTB,4				;UPS RDY
		call	disp_ups
		

lcd_init
		
  			movlw  	0x28            ;  4 bit, 2 Line, 5x7 font
  			call   	disp_cmd
			call	delay
  		;	movlw  	0x10            ;  display shift off
 		;	call   	disp_cmd
		;	call	delay
			movlw  	0x0E            ;  increment cursor
  			call   	disp_cmd
			call	delay
 			movlw  	0x01            ;  Clear the Display RAM
 			call   	disp_cmd
  			call   	delay           ;  Note, Can take up to 4.1 msecs
  		
			movlw  	0x06            ;  move the cursor to begining
  			call   	disp_cmd
			call	delay
  		;	movlw 	0x0C            ;  display on cursor off
  		;	call  	disp_cmd
		;	call	delay
  			return
delay
		movlw	d'236'			;2.5ms delay
		movwf	TMR0
loop1	btfss	INTCON,2
		goto	loop1	
		clrf	INTCON		        ; if overflow occur,clear INTCON
		return
d
;------------------------------------------------------------------------------------
;Display command for 4 bit LCD

disp_cmd                            ;  Send the Instruction to the LCD
 			 movwf	Temp            ;  Save the Temporary Value
 			 swapf  Temp, w         ;  Send the High Nybble
  			 bcf    LCD_RS          ;  RS = 0
 			 call   nibbleout
 			 movf   Temp, w         ;  Send the Low Nybble
 			 bcf    LCD_RS
 			 call   nibbleout
 			 return
;------------------------------------------------------------------------------------
;sending ASCII character to LCD
disp_write
  		;	addlw 	'0'             ;  Send nbr as ASCII character                      			  ;  Send the Character to the LCD
  			movwf  Temp             ;  Save the Temporary Value
  			swapf  Temp, w          ;  the High Nybble
  			bsf    LCD_RS           ;  RS = 1
  			call   nibbleout
  			movf   Temp, w          ;  Send the Low Nybble
  			bsf    LCD_RS
  			call   nibbleout
  			return
;------------------------------------------------------------------------------------ 
;sending lower and upper nibble
nibbleout                           ;  Send a nibble to the LCD
 			 movwf  PORTC
  			 bsf	LCD_E
			call	delay
 			 bcf	LCD_E
 			 nop
			 nop
 			 return

disp_main
	  
	  	
       movlw 	'M'                 ; output 'MAIN'
       call 	disp_write
       movlw 	'A'
       call 	disp_write
       movlw 	'I'
       call 	disp_write
       movlw 	'N'
       call 	disp_write

       movlw 	' '
       call 	disp_write
       movlw 	'N'
       call 	disp_write
       movlw 	'O'
       call 	disp_write
       movlw 	'R'               
       call 	disp_write
  
	   return

	end