Ericsson A2618 / A2628 lcd interface schematics. Click picture for details
;=====i2c lcd test for Ericsson A2618 / A2628 / Version 1.0======24/08/03== ; iic lcd driver: real PCF8548 with mirror higher and lower rows ; ra0,ra1,ra2,ra3 sdata, sclock, _reset,lcd power control ; rb0 to rb7 led outputs ; internal clock ; standard crystal 4.000 MHz XT - 1us pe instructiune ; Program realizat de Ing. Bergthaller Iulian-Alexandru ;------------------------------------------------------------ list p=16f84A;f=inhx8m _CP_OFF equ H'3FFF' ;code protect off _PWRTE_ON equ H'3FFF' ;Power on timer on _WDT_OFF equ H'3FFB' ;watch dog timer off _XT_OSC equ H'3FFD' ;crystal oscillator __CONFIG _CP_OFF & _PWRTE_ON & _WDT_OFF & _XT_OSC ;------------------------------------------------------------ ; cpu init status equ 03 porta equ 05 portb equ 06 count1 equ 0C count2 equ 0D count3 equ 0E transo equ 0F count4 equ 10 count5 equ 11 trisa equ 85 trisb equ 86 #DEFINE pwroff porta,3 #DEFINE rset porta,2 #DEFINE sclk porta,1 #DEFINE sdta porta,0 ;------------------------------------------------------------ ; bit init rp0 equ 5 w equ 0 f equ 1 ;------------------------------------------------------------ org 0 ; ;------------------------------------------------------------ init bsf status,rp0 ;switch to bank 1 movlw 0 ; porta and portb set to outputs movwf trisa movwf trisb bcf status,rp0 ;switch back to bank 0 movlw 0xFF movwf porta movwf portb ; led test ;*************************************************** start bcf rset bcf pwroff call halta ; rset time - min. 100ns bsf rset ; reset finished ;*************************************************** ;* Lcd init commands * ;*************************************************** call iict ; i2c start movlw 0x7A ; device write address call act ; i2c send subroutine movlw 0x00 ; many command bytes follow - see pcf8548 data sheet call act ; i2c send subroutine movlw 0x21 ; extended set command call act movlw 0x0F ; DSR=TSR=DO=1 lcd configuration - LSB up, mirror upper and lower rows call act movlw 0x15 ; bias call act movlw 0xEA ; Vop call act movlw 0x20 ; normal command set call act movlw 0x0C ; normal lcd mode call act call iicp ; i2c stop ;*************************************************** ;* Lcd data commands * ;*************************************************** call iict ; i2c start movlw 0x7A call act movlw 0x40 ; multiple data bytes call act call cbild ; clear screen call iicp ; i2c stop ;*************************************************** call iict ; i2c start movlw 0x7A call act movlw 0x00 ; (0x80 for just one command) call act movlw 0x44 ; Y address call act movlw 0xA7 ; X address call act call iicp ; i2c stop ;*************************************************** call iict ; i2c start movlw 0x7A call act movlw 0x40 ; multiple data bytes call act movlw 0x1F ;P call act movlw 0x05 call act movlw 0x07 call act movlw 0x00 call act movlw 0x1F ;H call act movlw 0x04 call act movlw 0x1F call act movlw 0x00 call act movlw 0x1F ;I call act movlw 0x00 call act movlw 0x1F ;L call act movlw 0x10 call act movlw 0x10 call act movlw 0x00 call act movlw 0x1F ;I call act movlw 0x00 call act movlw 0x1F ;P call act movlw 0x05 call act movlw 0x07 call act movlw 0x00 call act movlw 0x12 ;S call act movlw 0x15 call act movlw 0x09 call act movlw 0x00 call act call iicp ; i2c stop homa goto homa ;*************************************************** cbild movlw 0x08 ; 64 rows movwf count5 bcf sdta linee movlw 0x66 ; 102 columns movwf count4 wdh movlw 0x08 ; 8 bit data movwf count3 wbit bcf sclk call pause bsf sclk call pause bcf sclk decfsz count3,f goto wbit call ackp decfsz count4,f goto wdh decfsz count5,f goto linee retlw 00 ;*************************************************** act movwf transo ; iic data transmission call oled movlw 0x08 movwf count3 vbit bcf sclk call pause btfsc transo,7 bsf sdta btfss transo,7 bcf sdta call pause bsf sclk call pause bcf sclk call pause rlf transo,f decfsz count3,f goto vbit call ackp retlw 00 ;*************************************************** iicp bcf sdta ; stop condition module call pause bsf sclk call pause bsf sdta ; stop command call pause bcf sclk call pause retlw 00 ;*************************************************** iict bsf sdta ; start condition module bsf sclk call pause bcf sdta ; start command call pause bcf sclk call pause retlw 00 ;*************************************************** ackp bsf status,rp0 ;switch to bank 1 movlw 0x01 ; sdta set to input movwf trisa bcf status,rp0 ;switch back to bank 0 bsf sclk ; one clock step for acknowledge (no read data) call pause bcf sclk bsf status,rp0 ;switch to bank 1 movlw 0 ; porta set to output movwf trisa bcf status,rp0 ;switch back to bank 0 bcf sclk bcf sdta retlw 00 ;*************************************************** oled call halta ; iic data before transmission displayed on portb movlw 0x00 movwf portb movf transo,w movwf portb call halta movlw 0x00 movwf portb retlw 00 ;*************************************************** pause movlw 0xFF movwf count1 d1 decfsz count1,f goto d1 retlw 00 ;*************************************************** halta movlw 0x04 ; cca. 320ms delay movwf count3 r3 movlw 0x7F movwf count1 r1 movlw 0xFF movwf count2 r2 decfsz count2,f goto r2 decfsz count1,f goto r1 decfsz count3,f goto r3 retlw 00 ;------------------------------------------------------------ end ;============================================================
The hex code can be download from here.
The Ericsson A2618 lcd screen can be fited into a R320 screen housing.
Back to my home page