;******************************************************************************
;                                                                             *
;    Filename: hb16102_fkt.asm                                                *
;    Date:     19.04.2007                                                     *
;    File Version: 0.1                                                        *
;                                                                             *
;    Author: Thomas Fuchs                                                     *
;	 comment: funktionen des displays                                         *
;                                                                             *
;	 Anschluss des Displays:                                                  *
;		C0:  4, RS                                                            *
;       C1:  6, EN                                                            *
;       D0 - D7: Data 0 bis Data 7                                            *
;******************************************************************************
;                                                                             *
;    Files required:         P18F4685.INC                                     *
;                                                                             *
;******************************************************************************

	LIST P=18F4685		;directive to define processor
	#include <P18F4685.INC>	;processor specific variable definitions

;******************************************************************************
;Configuration bits

;   Oscillator Selection:
    CONFIG	OSC=IRCIO7            ;intern
	CONFIG  WDT=OFF               ;no Watchdog
	CONFIG  CP0=OFF,CP1=OFF,CP2=OFF     ;code protect off
	CONFIG  CP3=OFF,CP4=OFF,CP5=OFF,CPB=OFF,CPD=OFF
	CONFIG  WRT0=OFF,WRT1=OFF,WRT2=OFF,WRT3=OFF,WRT4=OFF,WRT5=OFF
	CONFIG  WRTB=OFF,WRTC=OFF,WRTD=OFF
	CONFIG  PBADEN=OFF            ;Port A as I/O
	CONFIG  LVP=OFF               ;low voltage programming

;******************************************************************************
;Variable definitions

 UDATA
WREG_TEMP	;variable used for context saving 
STATUS_TEMP	;variable used for context saving
BSR_TEMP	;variable used for context saving

 UDATA_ACS
	
lcddata		RES 1		;8bit zwischenspeicher: daten/cmd an gLCD
adrLSB 		RES 1		;8bit zwischenspeicher: address LSB
adrMSB		RES 1		;8bit zwischenspeicher: address MSB
rows   		RES 1		;8bit zwischenspeicher: rows (text)
lines  		RES 1		;8bit zwischenspeicher: lines (text)
loop   		RES 1		;warten in ms
loopcali   	RES 1		;zeahlvar fuer wait_1ms

;******************************************************************************
;Reset vector
; This code will start executing when a reset occurs.

		ORG	0x0000

		goto	Main			   ;go to start of main code

;******************************************************************************
;Start of main program
; The main program code is placed here.
Init:
	movlw	0x70				   ; maximale interne Frequenz 8MHz (cyc. = 0,5µs) setzen
	movwf	OSCCON	
	movlw	0x07
	movwf	CMCON
	movlw	0x0F
	movwf	ADCON1

	clrf 	WREG				   ; Akkumulator loeschen
	movwf 	TRISD				   ; PortD als Ausgang definieren	
	movwf 	TRISC				   ; PortC als Ausgang definieren	
	movwf 	TRISB		 		   ; PortB als Ausgang definieren	
	
	rcall 	set_display
	rcall	clear_display
 return

Main:	
;	*** main code goes here ***
	ORG 	0x0100

	movlw D'150'
	movwf loop
	rcall waitxms
	rcall Init				   ;Initialisieren

Main_:

	movlw 0x03					   ;home addr
	movwf lcddata
	rcall write_cmd
	movlw D'2'
	movwf loop
	rcall waitxms

	movlw 0x42					   ;write B
	rcall write_char
	movlw 0x6C					   ;write l
	rcall write_char
	movlw 0x75					   ;write u
	rcall write_char
	movlw 0x62					   ;write b
	rcall write_char
	movlw 0x62					   ;write b
	rcall write_char
	movlw D'50'
	movwf loop
	rcall waitxms

	movlw 0xC0					   ;Startadresse 2. Zeile
	rcall set_address
	movlw 0x21					   ;write !
	rcall write_char
	
	goto 	Main_
	return

set_display:
	movlw 0x0C					   ;display on
	movwf lcddata
	rcall write_cmd
	movlw 0x0B
	movwf loopcali
	rcall wait_4mues
	movlw 0x38					   ;2 lines
	movwf lcddata
	rcall write_cmd
	movlw 0x0B
	movwf loopcali
	rcall wait_4mues
 return

write_cmd:
  bcf LATC,0         			   ; command
  goto write_data1	               ; same code
write_data:
  bsf LATC,0                       ; data
write_data1:
  bsf LATC,1			           ; enable chip
  movff lcddata, LATD 			   ; write
  nop
  bcf LATC,1   				       ; disable chip
 return

write_char:
	movwf lcddata
	rcall write_data
	movlw 0x0B
	movwf loopcali
	rcall wait_4mues
 return

set_address:
	movwf lcddata
	rcall write_cmd
	movlw 0x0A
	movwf loopcali
	rcall wait_4mues
 return

clear_display:
	movlw 0x01					   ;clear display
	movwf lcddata
	rcall write_cmd
	movlw 0x0A
	movwf loopcali
	rcall wait_4mues
 return

waitxms:
  rcall wait_1ms
  decf loop
  bnz waitxms
 return

wait_1ms:
  movlw 0xF9
  movwf loopcali
wait_4mues:
  decf loopcali
  nop
  nop
  nop
  nop
  nop
  bnz wait_4mues
 return

;******************************************************************************
;End of program

		END