#include <REG51F380.H>

;-------------------------------------------------------------------------------------------------------------------;
;CONSTANT DEFINES FOR CHAR_NUM AND CHAR_STATE
;-------------------------------------------------------------------------------------------------------------------;
CHAR_0          EQU 0C0H                ;DEFINE CHARS FOR 8BITSEG
CHAR_1          EQU 0F9H
CHAR_2          EQU 0A4H
CHAR_3          EQU 0B0H
CHAR_4          EQU 099H
CHAR_5          EQU 092H
CHAR_6          EQU 082H
CHAR_7          EQU 0F8H
CHAR_8          EQU 080H
CHAR_9          EQU 090H

CHAR_L EQU 0C7H
CHAR_F EQU 68H
;-------------------------------------------------------------

S_RECOVER EQU 0
S_LOCKED EQU 1
S_OPEN EQU 2
S_ENCRYPT EQU 3
S_DESENCRYPT EQU 4
S_FAIL EQU 5

STATE DATA 30H
N_STATE DATA 31H
USER_KEY DATA 32H ;XDATA
SEC_KEY IDATA 50H

RECOVERY BIT 1
FECHADO BIT 0
VALID BIT 0

MASQ EQU 0A2H
KEYLEN EQU 4
KSET EQU P0.6
KLOAD EQU P0.7
TB EQU P2.7


CSEG AT 600H        ;caracteres segmento 8bits
    DIGITS_TABLE:
        DB CHAR_0, CHAR_1, CHAR_2, CHAR_3, CHAR_4, CHAR_5, CHAR_6, CHAR_7, CHAR_8, CHAR_9   ;0-9

CSEG AT 0H
    JMP RESET
;-------------------------------------------------------------------------------------------------
;       INIT_DEVICE
;-------------------------------------------------------------------------------------------------
PCA_Init:
    MOV  PCA0MD,    #000h
    RET
Port_IO_Init:
    MOV  XBR1,      #040h
    RET
TIMER_INIT:
    MOV FLSCL, #90H
    MOV CLKSEL, #30H
    RET
Init_Device:
    lcall PCA_Init
    lcall Port_IO_Init
    LCALL TIMER_INIT
    ret
;-------------------------------------------------------------------------------------------------
;       RESET
;-------------------------------------------------------------------------------------------------
RESET:
    ACALL Init_Device
    SETB KSET               ;ATIVAR BOTOES
    SETB KLOAD
    SETB TB
    SETB RECOVERY
    CLR FECHADO
    CLR VALID
    MOV R0, #SEC_KEY
    MOV R1, #USER_KEY
    MOV R3, #0H
    MOV A, #0H
    MOV B, #0H
    MOV STATE, #S_RECOVER
    MOV N_STATE, #S_RECOVER
    JMP STATE_MACHINE
;-------------------------------------------------------------------------------------------------
;       STATE MACHINE
;-------------------------------------------------------------------------------------------------
STATE_MACHINE:
    MOV STATE, N_STATE
    MOV A, STATE
    RL A
    MOV DPTR, #JMP_TABLE
    JMP @A+DPTR
JMP_TABLE:
    AJMP RECOVER
    AJMP LOCKED
    AJMP OPEN
    AJMP ENCRYPT
    AJMP DESENCRYPT
    AJMP FAIL

;-------------------------------------------------------------------------------------------------
;       STATE RECOVERY + STATE LOCKED ----USAM O MESMO CODIGO
;-------------------------------------------------------------------------------------------------
START:              ;aguarda que o utilizador carregue no kset para continuar o programa
    JB KSET, START
    JNB KSET, $
    RET

RECOVER:
    JMP DISPCHARS
LOCKED:
    MOV R1, #USER_KEY
    MOV P2, #CHAR_L
    CLR TB
    ACALL START

DISPCHARS:
    MOV DPTR, #DIGITS_TABLE
    MOV R3, #0H
DISPLAYBCD:
    MOV A, R3
    MOVC A, @A+DPTR
    MOV P2, A
    JNB FECHADO, BUTTONS
    CLR TB
BUTTONS:
    JNB KLOAD, SETNUM
    JB KSET, BUTTONS
INCREMENT:
    JNB KSET, $
    INC R3
    CJNE R3, #10, DISPLAYBCD
    MOV R3, #0H
    JMP DISPLAYBCD

SETNUM:
    JNB KLOAD, $
    JB RECOVERY, RELOAD_KEY
    JB FECHADO, LOCKED_2
    JMP SETNUM

RELOAD_KEY:
    MOV A, R3
    MOV @R1, A
    INC R1
    CJNE R1, #36H, DISPCHARS        ;è errado comparar com o endereco de memoria? deveriamos usar r4 para incremento e comparar r4 com keylen?
    CLR RECOVERY
    MOV N_STATE, #S_ENCRYPT
    JMP STATE_MACHINE

LOCKED_2:
    MOV A, R3
    MOV @R1, A
    INC R1
    CJNE R1, #36H, DISPCHARS        ;è errado comparar com o endereco de memoria? deveriamos usar r4 para incremento e comparar r4 com keylen?
    MOV N_STATE, #S_DESENCRYPT
    JMP STATE_MACHINE

;-------------------------------------------------------------------------------------------------
;       STATE DESENCRYPT
;-------------------------------------------------------------------------------------------------
DESENCRYPT:
    MOV R0, #SEC_KEY
    MOV R1, #USER_KEY
    MOV R3, #0H
    MOV N_STATE, #S_FAIL
    CLR VALID
DESENCRYPT_LOOP:
    MOV A, @R0
    MOV B, @R1
    XRL A, #MASQ
    CJNE A, B, STATE_MACHINE
    INC R0
    INC R1
    INC R3
    CJNE R3, #KEYLEN, DESENCRYPT_LOOP
    SETB VALID
    SETB TB
    CLR FECHADO
    MOV N_STATE, #S_OPEN
    JMP STATE_MACHINE

;-------------------------------------------------------------------------------------------------
;       STATE ENCRYPT
;-------------------------------------------------------------------------------------------------
ENCRYPT:
    MOV R0, #SEC_KEY
    MOV R1, #USER_KEY
    MOV R3, #0H
ENCRYPT_LOOP:
    MOV A, @R1
    XRL A, #MASQ
    MOV @R0, A
    INC R3
    INC R1
    INC R0
    CJNE R3, #KEYLEN, ENCRYPT_LOOP      ;precisamos checkar o kload(segundo fluxograma)??? ou outra coisa antes de ir para estado locked
    MOV N_STATE, #S_LOCKED
    SETB FECHADO
    JMP STATE_MACHINE

;-------------------------------------------------------------------------------------------------
;       STATE FAIL
;-------------------------------------------------------------------------------------------------
FAIL:
    MOV P2, #CHAR_F
    CLR TB                      ;OU PODEMOS IGNORAR O TB NO CASO DE BLOQUEIO?
    ;engodo do timer
    JMP FAIL
    MOV N_STATE, #S_LOCKED
    JMP STATE_MACHINE
;-------------------------------------------------------------------------------------------------
;       STATE OPEN
;-------------------------------------------------------------------------------------------------
OPEN:
    JNB VALID, $
    MOV P2, #CHAR_0
    JNB KLOAD, CLOSE
    JB KSET, OPEN
    JNB KSET, $
NEW_PASSWORD:


CLOSE:
    JNB KLOAD, $
    MOV N_STATE, #S_LOCKED
    JMP STATE_MACHINE

END