; SERVO REQUIRES A SIGNAL OF 50Hz WHICH IS 20ms.
; Position "0" ( 1.5 ms of 20 ms pulse) turns in the middle.
; Position "+90" ( 2ms of 20 ms pulse) turns all the way to the right.
; Position "-90" ( 1ms of 20 ms pulse) turns all the way to the left.
; Position "+45" ( 1.75ms of 20 ms pulse) turns half the way to the right.
; Position "-45" ( 1.25ms of 20 ms pulse) turns half the way to the left.
RS EQU P2.1
RW EQU P2.2
E EQU P2.3
CSG EQU P2.4
PARK1 EQU P0.1
PARK2 EQU P0.2
PARK3 EQU P0.3
;LCD INITIALIZATION
MOV A, #00111000B ; INITIATE LCD #38H
ACALL COMMANDWRT
ACALL DELAY
MOV A, #00001110B ; DISPLAY ON CURSOR OFF #0CH
ACALL COMMANDWRT
ACALL DELAY
MOV A, #00000001B ; CLEAR LCD #01H
ACALL COMMANDWRT
ACALL DELAY
;PRINTING A STRING
MOV DPTR, #STRINGDATA1
STRING1: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
ACALL DELAYMSG
INC DPTR
JNZ STRING1
ACALL PARKCHECK
JB P0.0, $
MOV TMOD, #00010000B ;TIMER 1, MODE 1 - 16BIT MODE
MAIN:
JB P0.0, CON1
SJMP TURN_LEFT_90
CON1:
CALL CENTER_POS
SJMP MAIN
TURN_LEFT_90:
ACALL CLEARMSG
SETB CSG
CALL LEFT_POS
SJMP MAIN
;;;;;;;;;;;;;;;;;;SERVO POSITIONS;;;;;;;;;;;;;;;;;;;;;;
CENTER_POS:
; Position "0" (1.5 ms pulse) is middle.
; High Part = 1.5ms
; 1.5ms / (1 / 11.0592 MHz) = 1.5 ms / 1.085 µs = 1382
; 65536 - 1382 = 64154 Dec = FA9A Hex
; Low Part = 18.5ms
; 18.5ms / (1 / 11.0592 MHz) = 18.5 ms / 1.085 µs = 17050
; 65536 - 17050 = 48486 Dec = BD66 Hex
;JNB CSG,CONTINUE
;JB P0.0,GC
SETB P2.0
MOV TL1, #0B2H ;LET THIS VALUE = 0B2 FOR A PRECISE CENTER ANGLE AS MUCH AS POSSIBLE
MOV TH1, #0FAH ;Puts it back to the center
SETB TR1 ; Run Timer
CALL HIGH_SIGNAL
MOV TL1, #66H
MOV TH1, #0BDH ; Allow it to turn
SETB TR1 ; Run Timer
CALL LOW_SIGNAL
JNB CSG,CONTINUE
ACALL STR3WRT
CONTINUE:
RET
LEFT_POS:
; Position "-90" (1 ms pulse) is 90 degrees to the left.
; High Part = 1 ms
; 1 ms / (1 / 11.0592 MHz) = 1 ms / 1.085 µs = 921
; 65536 - 921 = 64615 Dec = FC67 Hex
; Low Part = 19 ms
; 19 ms / (1 / 11.0592 MHz) = 19 ms / 1.085 µs = 17511
; 65536 - 17511 = 48025 Dec = BB99 Hex
ACALL CLEARMSG
MOV DPTR, #STRINGDATA2
STRING2: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
INC DPTR
JNZ STRING2
ACALL CLEARMSG
MOV TL1, #7CH ;LET THIS VALUE = 7C FOR A PRECISE -90 ANGLE
MOV TH1, #0FFH
SETB TR1 ; Run Timer
CALL HIGH_SIGNAL
MOV TL1, #99H
MOV TH1, #0BBH
SETB TR1 ; Run Timer
CALL LOW_SIGNAL
RET
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;TIMER OF SIGNALS;;;;;;;;;;;;;;;;;;;;;;;;;;;;
HIGH_SIGNAL:
JNB TF1, $ ;Wait till Timer overflow
CLR TR1
CLR P2.0 ;HIGH TO LOW TRANSITION
CLR TF1
RET
LOW_SIGNAL:
JNB TF1, $ ;Wait till Timer overflow
CLR TR1
SETB P2.0 ;LOW TO HIGH TRANSITION
CLR TF1
RET
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;COMMAND SUB-ROUTINE FOR LCD CONTROL
COMMANDWRT:
MOV P1, A ;SEND DATA TO P1
CLR RS ;RS=0 FOR COMMAND
CLR RW ;R/W=0 FOR WRITE
SETB E ;E=1 FOR HIGH PULSE
ACALL DELAY ;SOME DELAY
CLR E ;E=0 FOR H-L PULSE
RET
;SUBROUTINE FOR DATA LACTCHING TO LCD
DATAWRT:
MOV P1, A
SETB RS ;;RS=1 FOR DATA
CLR RW
SETB E
ACALL DELAY
CLR E
RET
DELAY:
MOV R0, #255
X: MOV R1, #255
DJNZ R1, $
DJNZ R0, X
RET
DELAYMSG:
MOV R0, #1
Y: MOV R1, #1
DJNZ R1, $
DJNZ R0, Y
RET
CLEARMSG: MOV A, #00000001B ; CLEAR LCD #01H
ACALL COMMANDWRT
ACALL DELAYMSG
RET
STR3WRT:
CLR CSG
MOV DPTR, #STRINGDATA3
STRING3: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
ACALL DELAYMSG
INC DPTR
JNZ STRING3
ACALL PARKCHECK
RET
STR4WRT:
MOV DPTR, #STRINGDATA4
STRING4: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
ACALL DELAYMSG
INC DPTR
JNZ STRING4
RET
STR5WRT:
MOV DPTR, #STRINGDATA5
STRING5: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
ACALL DELAYMSG
INC DPTR
JNZ STRING5
RET
STR6WRT:
MOV DPTR, #STRINGDATA6
STRING6: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
ACALL DELAYMSG
INC DPTR
JNZ STRING6
RET
STR7WRT:
MOV DPTR, #STRINGDATA7
STRING7: CLR A
MOVC A, @A+DPTR
ACALL DATAWRT
ACALL DELAYMSG
INC DPTR
JNZ STRING7
RET
PARKCHECK:
MOV A,#0C0H
ACALL COMMANDWRT
;0000 -> 0H
;0010 -> 2H
;0100 -> 4H
;0110 -> 6H
;1000 -> 8H
;1010 -> AH
;1100 -> CH
;1110 -> EH
MOV A,P0
ANL A,#00001110B
CJNE A,#0H,NEXT1
ACALL STR4WRT
NEXT1:
CJNE A,#2H,NEXT2 ;;;;;;;;;;;;;;;
ACALL STR5WRT
NEXT2:
CJNE A,#4H,NEXT3
ACALL STR5WRT
NEXT3:
CJNE A,#8H,NEXT4
ACALL STR5WRT
NEXT4:
CJNE A,#6H,NEXT5 ;;;;;;;;;;;;;;;;;;;;
ACALL STR6WRT
NEXT5:
CJNE A,#0AH,NEXT6 ;;;;;;;;;;;;;;;;
ACALL STR6WRT
NEXT6:
CJNE A,#0CH,NEXT7
ACALL STR6WRT
NEXT7:
CJNE A,#0EH,NEXT8
ACALL STR7WRT
NEXT8:
RET
ORG 300H
STRINGDATA1: DB "Welcome !!!" ,0
STRINGDATA2: DB "Gate Opening " ,0
STRINGDATA3: DB "Gate Closed" ,0
STRINGDATA4: DB "Slots Left: 3" ,0
STRINGDATA5: DB "Slots Left: 2" ,0
STRINGDATA6: DB "Slots Left: 1" ,0
STRINGDATA7: DB "Slots Left: 0" ,0
END
This is the code if anyone can tell me why my lcd is showing white blocks
