UPDATE

Makefile

@@ -0,0 +1,18 @@
+EXTRA_CFLAGS =  -Wall
+KDIR = /lib/modules/`uname -r`/build
+obj-m        =  lcd_driver.o
+all: ko app_test
+
+ko:
+	make -C $(KDIR) M=`pwd`
+
+app_test: app_test.o lcd_lib.o
+	gcc -o app_test app_test.o lcd_lib.o
+
+app_test.o: app_test.c
+	gcc -c app_test.c
+lcd_lib.o: lcd_lib.c lcd_lib.h
+	gcc -c lcd_lib.c
+clean:
+	make -C $(KDIR) M=`pwd` clean
+	rm app_test

PBL.S

@@ -0,0 +1,219 @@
+.data
+
+
+    filepath: .asciz "/dev/lcd_1602"
+    r: .ascii "r"
+    a: .ascii "a"
+    i: .ascii "i"
+    e: .ascii "e"
+    l: .ascii "l"
+    p: .ascii "p"
+    u: .ascii "u"
+    c: .ascii "c"
+    n: .ascii "n"
+    P: .ascii "P"
+    person: .ascii "¥"
+    bloco: .ascii "#"
+    excl: .ascii "!"
+    esp: .ascii " "
+
+    @my struct
+    .align 4
+    x: .word 2
+    y: .word 1
+    cenario: .word 0,0,1,1,0,0,0,1,1,1,0,0,1,1,1,1 
+    .equ count, 80000000
+
+.text
+.global main
+
+main:
+    LDR r11,=count
+    BL clear
+    BL gameplay
+    LDR R1,=i
+    MOV R7, #4
+    MOV R0, #1
+    MOV R2, #12
+    SWI 0
+    B end
+gameplay:
+    BL set_position_DOWN
+	LDR R10, =cenario
+	MOV R3,#16
+	B moveCen
+
+moveCen:
+	CMP R3, #0
+	BEQ movingOn
+	LDR R6, [R10, #0]
+	CMP R6, #0
+	BEQ adsEsp         	@ Se for 0 escreve espaço
+	B adsBlo
+
+adsEsp:
+		LDR R9,=esp
+		BL write
+		ADD R10, R10, #4
+		SUB R3, R3, #1
+		B moveCen
+
+adsBlo:
+		LDR R9,=bloco
+		BL write
+		ADD R10, R10, #4
+		SUB R3, R3, #1
+		B moveCen
+
+movingOn:
+    LDR r10,=cenario			@ Move a base do vetor para o registrador r9
+    MOV R3, #16
+    B moving					@ O objetivo dele é colocar a primeira posição do vetor para a ultima sem comprometer a ordem do array
+
+moving:		
+    CMP R3, #0 
+    BEQ delay			@ Se r2 for igual a 0 o processo vai para o delay
+    BL swap
+    ADD R10, R10, #4 				@ Vai para a proxima posição do array "r9[i] = r9[i+1]"
+    B moving
+
+swap:								@ Ele troca a primeira posição para a segunda posição
+    LDR R6, [R10, #0]
+    LDR R7, [R10, #4]
+    STR R7, [R10, #0]
+    STR R6, [R10, #4]
+    SUB R3, R3, #1
+    LDR R1,=i
+    MOV R7, #4
+    MOV R0, #1
+    MOV R2, #1
+    SWI 0
+    BX LR
+
+delay:	
+	SUB r11, r11, #1
+	CMP r11, #0
+	BNE delay
+	LDR r11,=count
+	B gameplay
+
+
+end:
+    B end
+
+write:
+    SUB sp, sp, #8
+    STR lr, [sp]
+    BL open
+    MOV R7, #54                  @IOCTL
+    MOV R1, #4                      @put flag
+    MOV R2,R9               @Valor deve ser atribuido antes da chamada da função
+    SWI 0
+    BL close
+    LDR LR, [sp]
+    ADD sp, sp, #8
+    BX LR
+
+set_position_DOWN:
+    SUB sp, sp, #8
+    STR lr, [sp]
+    BL open
+    MOV R7, #54                  @IOCTL
+    MOV R1, #10
+    LDR R2,=x
+    SWI 0
+    LDR LR, [sp]
+    ADD sp, sp, #8
+    BX LR
+
+set_position_UP:
+    SUB sp, sp, #8
+    STR lr, [sp]
+    BL open
+    MOV R7, #54                  @IOCTL
+    MOV R1, #10
+    LDR R2,=y 
+    SWI 0
+    LDR LR, [sp]
+    ADD sp, sp, #8
+    BX LR
+
+open:
+    MOV R7, #5                  @ função open
+    LDR R0, =filepath          @ file pointer 
+    MOV R1, #0                  @Permissão de adm
+    MOV R2, #00700              @flag
+    SWI 0
+    BX LR
+
+close: 
+
+    MOV R0, R9
+    MOV R7, #6
+    SWI 0               @Close
+    BX LR
+
+clear:
+    SUB sp, sp, #8
+    STR LR, [sp]
+    BL open
+    MOV R7, #54                  @IOCTL
+    MOV R1, #1                      @clear flag
+    SWI 0
+    BL close
+    LDR LR, [sp]
+    ADD sp, sp, #8
+    BX LR
+
+home_title:
+    SUB sp, sp, #8
+    STR LR, [sp]
+    LDR R9,=esp
+    BL write
+    BL write
+    BL write
+    LDR R9,=P
+    BL write
+    LDR R9,=u
+    BL write
+    LDR R9,=l
+    BL write
+    LDR R9,=e
+    BL write
+
+    LDR R9,=esp
+    BL write
+    LDR R9,=p
+    BL write
+    LDR R9,=a
+    BL write
+    LDR R9,=r
+    BL write
+    LDR R9,=a
+    BL write
+    BL set_position_DOWN
+    LDR R9,=esp
+    BL write
+    BL write
+    BL write
+    BL write
+    LDR R9,=i
+    BL write
+    LDR R9,=n
+    BL write
+    LDR R9,=i
+    BL write
+    LDR R9,=c
+    BL write
+    LDR R9,=i
+    BL write
+    LDR R9,=a
+    BL write
+    LDR R9,=r
+    BL write
+    LDR R9,=excl
+    BL write
+    LDR LR, [sp]
+    ADD sp, sp, #8
+    BX LR
+

README.md

@@ -1 +1,23 @@
-# JumpGameSBC
+# LCD16x2_Driver
+
+This is a kernel level Linux Device driver to control a 16x2 character LCD (with HD44780 LCD controller) with 4 bit mode.
+
+  - Provide API for app in userspace to comminicate with LCD
+  - The LCD is interfaced with a micro-controller using GPIO pins.
+  - Driver is written on the Raspberry Pi 3 B, the kernel version 4.19.75-v7+
+
+# List of APIs
+
+| Function | Description |
+| ------ | ------ |
+| __void _lcd_init_(void)__ | __Init LCD, set default configure (display + cursor + blink on)__ |
+| __void _lcd_clear_display_(void)__ | __Clear display and set cursor to home position__ |
+| __void _lcd_put_char_(char c)__ | __Display character at current cursor position__ |
+| __void _lcd_put_string_(const char *s)__ | __Display string at current cursor position__ |
+| __void _lcd_put_string_super_(const char *s)__ | __Clear display and display on 2 line if string length > 16__ |
+| __void _lcd_goto_xy_(unsigned char x, unsigned char y)__ | __Set cursor to specified position__ |
+| __void _lcd_scroll_left_(void)__ | __scroll text to left__ |
+| __void _lcd_scroll_right_(void)__ | __scroll 2 line text to right__ |
+| __void _lcd_set_display_(unsigned char display, unsigned char cursor, unsigned char blink)__ | __Set cursor to home position__ |
+| __void _lcd_upload_custom_char_(unsigned char location, unsigned char *charmap)__ | __Upload data for custom char to CGRAM__ |
+| __void _lcd_set_auto_scroll_(unsigned char status)__ | __Set enable or disable auto move all the text one space to the left each time a letter is added__ |