;LCD text demo - 4 bit mode ;Nigel Goodwin 2002 LIST p=16F628 ;tell assembler what chip we are using include "P16F628.inc" ;include the defaults for the chip ERRORLEVEL 0, -302 ;suppress bank selection messages __config 0x3D18 ;sets the configuration settings (oscillator type etc.) cblock 0x20 ;start of general purpose registers TIMERTCS ; Timer1 túlcsordulások számlálója TIMERTCS1 TIMERTCS2 TULCSORDUL TEMP1L ; CCP első érték átmeneti tároló, alsó bit TEMP1H ; CCP első érték átmeneti tároló, felső bit TEMP2L ; CCP második érték átmeneti tároló, alsó bit TEMP2H ; CCP második érték átmeneti tároló, felső bit TIMEL ; Idő alsó bájt TIMEH ; Idő felső bájt count ; Számláló a ciklus-rutinokhoz. count1 ; Számlálók a késleltető rutinhoz. counta countb count2 tmp1 ; Átmeneti tárolás. tmp2 templcd ; Átmeneti tároló a 4 bites módhoz. templcd2 nratorH ; Számláló és eredmény felső bájt nratorM ; Számláló és eredmény középső bájt nratorL ; Számláló és eredmény alsó bájt denomH ; Nevező felső bájt denomM ; Nevező középső bájt denomL ; Nevező alsó bájt remainH ; Maradék felső bájt remainM ; Maradék középső bájt remainL ; Maradék alsó bájt BCount ; Számláló az osztáshoz shiftH ; Segédregiszter az osztáshoz shiftM ; Segédregiszter az osztáshoz shiftL ; Segédregiszter az osztáshoz d0 ; A bináris ASCII átalakítás segédregisztere d1 ; A bináris ASCII átalakítás segédregisztere d2 ; A bináris ASCII átalakítás segédregisztere endc LCD_PORT Equ PORTA LCD_TRIS Equ TRISA LCD_RS Equ 0x04 ;LCD handshake lines LCD_RW Equ 0x06 LCD_E Equ 0x07 org 0x0000 movlw 0x07 movwf CMCON ;turn comparators off (make it like a 16F84) Initialise clrf count clrf PORTA clrf PORTB SetPorts bsf STATUS,RP0 ;select bank 1 movlw 0x00 ;make all pins outputs movwf LCD_TRIS movlw b'00001000' movwf TRISB movlw 0x04 movwf PIE1 bcf STATUS,RP0 ;select bank 0 movlw 0x05 movwf CCP1CON movlw 0x01 movwf T1CON call Delay100 ;wait for LCD to settle call LCD_Init ;setup LCD clrf count ;set counter register to zero Message movlw HIGH Text movwf PCLATH movf count, w ;put counter value in W call Text ;get a character from the text table xorlw 0x00 ;is it a zero? btfsc STATUS, Z goto EndMessage call LCD_Char call Delay20 incf count, f goto Message EndMessage movlw 0x09 call LCD_Line1W clrf PIR1 START: btfss PIR1,2 goto START MEGSZ_CCP: bcf PIR1,2 ; A megszakítást jelző bit törlése movfw CCPR1L ; W = CCPR2L movwf TEMP1L ; TEMP1L = CCPR2L ("elso érték" alsó bájt elmentve) movfw CCPR1H ; W = CCPR2H movwf TEMP1H ; TEMP1H = CCPR2H ("elso érték" felső bájt elmentve) movfw TIMERTCS movwf TIMERTCS1 KIVON: movfw TEMP2L subwf TEMP1L,w movwf TIMEL movfw TEMP2H skpc incfsz TEMP2H,w subwf TEMP1H,w movwf TIMEH movfw TIMERTCS2 skpc incfsz TIMERTCS2,w subwf TIMERTCS1,w movwf TULCSORDUL ; movfw TEMP2L ;elmentjük az eredményeket ; movwf TIMEL ; movfw TEMP2H ; movwf TIMEH ; movfw TIMERTCS2 ; movwf TULCSORDUL movfw TEMP1L ;Az új lesz a régi movwf TEMP2L movfw TEMP1H movwf TEMP2H movfw TIMERTCS1 movwf TIMERTCS2 ;*************** Idtartamszmts ******************************************** ; Kerk kerlet 1,2 m. Mivel a m/s s km/h kztt 3,6 a vltszm a s s a us kztt 1 000 000, ; gy kell szmolni, hogy 1,2x3 600 000/id (teht 4 320 000/id) . Ez km/h-t ad egsz rtkben. ; szmll: nratorH nratorM nratorL ; nevez: denomH denomM denomL ; Az eredmny a nratorH nratorM nratorL regiszterekbe kerl Oszt: movlw b'01000001' ; A szmll 24 bites regiszterbe 4 320 000-et tltnk movwf nratorH movlw b'11101011' movwf nratorM movlw b'00000000' movwf nratorL movfw TULCSORDUL movwf denomH movfw TIMEH movwf denomM movfw TIMEL movwf denomL Divide_24x24: movlw .24 ; set decimal 24 loop count movwf BCount movf nratorH,w ; copy Numerator into Shift Holding ram registers movwf shiftH movf nratorM,w movwf shiftM movf nratorL,w movwf shiftL clrf nratorH ; clear final Answer Numerator Ram locations clrf nratorM clrf nratorL ; clrf remainH ; clear final Answer Remainder Ram locations clrf remainM clrf remainL dloop: bcf STATUS, C ; bit clear Carry Flag in STATUS register rlf shiftL, f ; Shift numerator(dividend) Left to move rlf shiftM, f ; next bit to remainder rlf shiftH, f ; and shift in next bit of result rlf remainL, f ; shift carry (next Dividend bit) into remainder rlf remainM, f rlf remainH, f movf denomH,w subwf remainH,w ; subtract divsor(denomH) from(newly shifted left) Remainder HIGH byte. btfss STATUS, Z goto nochk ; skip if result was ZERO from good subtraction result ; movf denomM,w subwf remainM,w ; subtract divsor(denomM) from(newly shifted left) Remainder MIDDLE byte. btfss STATUS, Z goto nochk ; skip if result was ZERO from good subtraction result ; movf denomL,w subwf remainL,w ; subtract divsor(denomL) from(newly shifted left) Remainder LOW byte. nochk: btfss STATUS, C ; Carry SET? then denom is larger than reemainder goto nogo ; movf denomL,w subwf remainL, f ; Subtract denominator from remainder value in Low Byte btfsc STATUS, C ; Carry Set? Then execute fixup code for when a borrow is generated goto nodec_remainM ; when no borrow bit is needed from the higher byte positions. decf remainM, f ; Decrement to Borrow from Middle Byte, because carry was SET. movf remainM,w xorlw 0xff ; Check if rollover from Borrow occurred. remainM value went from 0 to 0xFF btfsc STATUS, Z decf remainH, f ; ZERO bit set, yes rollover, so Decrement to Borrow from High Byte, too! nodec_remainM: movf denomM,w subwf remainM, f ; Subtract denominator from remainder value in Middle Byte btfss STATUS, C decf remainH ,f ; Decrement High Byte, to borrow 1 bit movf denomH,w subwf remainH, f ; Subtract denominator from remainder value in High Byte bsf STATUS, C ; set CARRY bit to rotate in Numerator Result next. nogo: rlf nratorL, f ; rotate Numerator result left 1 bit rlf nratorM, f rlf nratorH, f decfsz BCount, f ; decrement the Loop Bit Counter goto dloop movfw nratorL ;***************** Konverzi (binris/ASCII) *** clrf d2 clrf d1 clrf d0 ; Test if W is more than 199 (200 to 255) addlw .256 - .200 btfss STATUS,C goto digit100 bsf d2,1 ; Here we are in the 200 - 255 range, so it is possible to ; skip the .100 and .80 parts addlw .256 - .80 goto digit40 ; Now, we have a number from -200 to -1 (0..199), ; we add 100 to detect -100 to -1 (100..199). digit100 addlw .100 btfss STATUS,C goto $+3 bsf d2,0 addlw .256 - .100 ; Now, we have a number from -100 to -1 (0..99), ; we add 20 to detect -20 to -1 (80..99). addlw .20 btfss STATUS,C goto digit40 bsf d1,3 ; We skip the 4 and 2, as the largest value is 8 + 1 = 9. addlw .256 - .20 goto digit10 ; Now, we have a number from -80 to -1 (0..79), ; we add 40 to detect -40 to -1 (40..79). digit40 addlw .40 btfss STATUS,C goto $+3 bsf d1,2 addlw .256 - .40 ; Now, we have a number from -40 to -1 (0..39), ; we add 20 to detect -20 to -1 (20..39). addlw .20 btfss STATUS,C goto $+3 bsf d1,1 addlw .256 - .20 ; Now, we have a number from -20 to -1 (0..19), ; we add 10 to detect -10 to -1 (10..19). digit10 addlw .10 btfss STATUS,C goto $+3 bsf d1,0 addlw .256 - .10 ; Now, we have a number from -10 to -1 (0..9), ; we add 58 to bring it from 48 to 57 (0..9). addlw .58 movwf d0 movlw 0x30 xorwf d1,f xorwf d2,f ;********************** Kijelzs vezrlse ************************************ ; movlw 0x09 ; call LCD_Line2W ; A sebessg kijelzs helyre lltja a kurzort ; movlw 0x01 ; subwf NULLA,W ; 0-bl kivonjuk a NULLA regiszter rtkt ; btfsc STATUS,C ; Ha a NULLA regiszter rtke tbb mint 0 ; goto Nem_megy ; akkor nullkat runk ki a sebessghez movfw d2 call LCD_Char movfw d1 call LCD_Char movfw d0 call LCD_Char ; bsf T1CON,0 ; TIMER1 indtsa ; bsf INTCON,7 ; Megszaktsok engedlyezse ; clrf NULLA ; goto START Stop goto EndMessage ;endless loop ;Subroutines and text tables ;LCD routines ;Initialise LCD LCD_Init movlw 0x20 ;Set 4 bit mode call LCD_Cmd movlw 0x28 ;Set display shift call LCD_Cmd movlw 0x06 ;Set display character mode call LCD_Cmd movlw 0x0d ;Set display on/off and cursor command call LCD_Cmd call LCD_Clr ;clear display retlw 0x00 ; command set routine LCD_Cmd movwf templcd swapf templcd, w ;send upper nibble andlw 0x0f ;clear upper 4 bits of W movwf LCD_PORT bcf LCD_PORT, LCD_RS ;RS line to 0 call Pulse_e ;Pulse the E line high movf templcd, w ;send lower nibble andlw 0x0f ;clear upper 4 bits of W movwf LCD_PORT bcf LCD_PORT, LCD_RS ;RS line to 0 call Pulse_e ;Pulse the E line high call Delay5 retlw 0x00 LCD_CharD addlw 0x30 LCD_Char movwf templcd swapf templcd, w ;send upper nibble andlw 0x0f ;clear upper 4 bits of W movwf LCD_PORT bsf LCD_PORT, LCD_RS ;RS line to 1 call Pulse_e ;Pulse the E line high movf templcd, w ;send lower nibble andlw 0x0f ;clear upper 4 bits of W movwf LCD_PORT bsf LCD_PORT, LCD_RS ;RS line to 1 call Pulse_e ;Pulse the E line high call Delay5 retlw 0x00 LCD_Line1 movlw 0x80 ;move to 1st row, first column call LCD_Cmd retlw 0x00 LCD_Line2 movlw 0xc0 ;move to 2nd row, first column call LCD_Cmd retlw 0x00 LCD_Line1W addlw 0x80 ;move to 1st row, column W call LCD_Cmd retlw 0x00 LCD_Line2W addlw 0xc0 ;move to 2nd row, column W call LCD_Cmd retlw 0x00 LCD_CurOn movlw 0x0d ;Set display on/off and cursor command call LCD_Cmd retlw 0x00 LCD_CurOff movlw 0x0c ;Set display on/off and cursor command call LCD_Cmd retlw 0x00 LCD_Clr movlw 0x01 ;Clear display call LCD_Cmd retlw 0x00 LCD_HEX movwf tmp1 swapf tmp1, w andlw 0x0f call HEX_Table call LCD_Char movf tmp1, w andlw 0x0f call HEX_Table call LCD_Char retlw 0x00 Delay255 movlw 0xff ;delay 255 mS goto k0 Delay100 movlw d'100' ;delay 100mS goto k0 Delay50 movlw d'50' ;delay 50mS goto k0 Delay20 movlw d'20' ;delay 20mS goto k0 Delay5 movlw 0x05 ;delay 5.000 ms (4 MHz clock) k0 movwf count1 k1 movlw 0xC7 ;delay 1mS movwf counta movlw 0x01 movwf countb Delay_0 decfsz counta, f goto $+2 decfsz countb, f goto Delay_0 decfsz count1 ,f goto k1 retlw 0x00 Pulse_e bsf LCD_PORT, LCD_E nop bcf LCD_PORT, LCD_E retlw 0x00 ;end of LCD routines HEX_Table ADDWF PCL , f RETLW 0x30 RETLW 0x31 RETLW 0x32 RETLW 0x33 RETLW 0x34 RETLW 0x35 RETLW 0x36 RETLW 0x37 RETLW 0x38 RETLW 0x39 RETLW 0x41 RETLW 0x42 RETLW 0x43 RETLW 0x44 RETLW 0x45 RETLW 0x46 org 0x0400 Text addwf PCL, f retlw 'S' retlw 'e' retlw 'b' retlw 'e' retlw 's' retlw 's' retlw 'e' retlw 'g' retlw ':' retlw ' ' retlw ' ' retlw ' ' retlw 'k' retlw 'm' retlw '/' retlw 'h' retlw 0x00 end