//  GMS6-SR6, GT-723F GPS Monitor   2015.3.27
// ===> LCD ACM1602N1-FLW-FBW M01 Akizuki
#include<16F1938.h>
//#include<math.h>
//#device ADC=10
#fuses INTRC_IO,NOWDT,NOPROTECT,NOMCLR,BROWNOUT	//
#use delay(clock= 16000000)
//#use delay  (clock=10000000)
#use i2c(MASTER,SDA=PIN_C4,SCL=PIN_C3,FAST,NOFORCE_SW)
#use rs232(BAUD =  9600, XMIT = PIN_C6, RCV = PIN_C7, STREAM=COM_A)
//#use RS232(PARITY=N, BAUD=9600,XMIT=PIN_B5, RCV=PIN_B2)
//#use rs232(BAUD = 38400, XMIT = PIN_B5, RCV = PIN_B2, STREAM=COM_B)

// ACM1602
#define LCD_ADD             0xA0    // ACM1602 Slave Address
void LCD_cmd(unsigned char cmd);
void LCD_Clear();
void LCD_Setline(unsigned char line);
void LCD_init();
void LCD_data(unsigned char data);
void LCD_space(int8 n);
void LCD_Clear_line2();
void isr_rcv();
void clear_words();
void cut_down();

int8 deque();

#define line_1              0x80
#define line_2              0xC0
#define data_out            0x80
#define cmd_code            0x00

static int8  rate;

#define MAX 200             // Size of Ring Buffer
static int16 tail, head;
static char  buff[MAX];
#define gps_max  200        // GPS Buffer
static char gps[max];

#define word_max 200        // Cut down in a word
static char words[word_max];
#define l_word    12        // Length a word

#int_rda
void isr_rcv()              // enqueue
{
    char C;
    C = (0x7f & fgetc(COM_A));
    buff[tail++] = C;
    if( tail >= MAX ){
        tail = 0;
    }
}

int8 deque(){              // dequeue
    int8 ret_val ;          // if no data ==> return null

    ret_val = 0;
    if(tail != head){
        ret_val = buff[head++];
        if( head >= MAX){
            head = 0;
        }
    }
    return(ret_val);
}

//  ==========================================
void main(){
    char C;

    char gps_pntr ;
    char title1[17]     = "GT-723F GPS Moni";
    char title_1938[25] = "PIC16F1938 GPS Monitor";
    int16 cnt;
    int16 pntr;

    set_tris_b(0xfe);
    set_tris_c(0xfe);
    output_low(PIN_B0);
    delay_ms(1000);
    LCD_init();
    LCD_Setline(line_1);
    for(cnt=0 ; cnt < 16; cnt++){
        LCD_data(0x30 + cnt);
    }
    delay_ms(1000);
    LCD_Setline(line_1);
    for(cnt=0 ; cnt < 16; cnt++){
        LCD_data( title1[cnt] );
    }

    LCD_Setline(line_1);
    delay_ms(1000);
    for(cnt=0 ; cnt < 22; cnt++){
        LCD_data( title_1938[cnt] );
        fprintf(COM_A,title_1938[cnt]);
    }
    fprintf(COM_A,'\r');
    fprintf(COM_A,'\n');

    delay_ms(1000);
    output_high(PIN_B0);         // GPS Power ON
    LCD_Setline(line_2);

    gps_pntr = 0;
    tail = head  = 0;
    cnt  = rate = 0;
    enable_interrupts(INT_RDA);
    enable_interrupts(GLOBAL);

    while(true) {
        C = deque();
        if(C != 0x00){
            if( gps_pntr < gps_max ){           // 0---->99
                gps[gps_pntr++] = C;
            }
            if( C == '$'){
                gps_pntr = 0;
            }
            if (  C == '\r'){
                clear_words();              // Clear at Space code
                cut_down();                 // Cut down in a word

                if( gps[3] == 'G'){
                    rate++;
                    if(rate & 0x01){
                        output_high(PIN_C0);
                    }
                    else{
                        output_low(PIN_C0);
                    }

                    LCD_Setline(line_1);
                    for( cnt=6 ;cnt<=11;cnt++){  // Time
                        LCD_data( gps[cnt] );
                    }
                    LCD_data('T');
                    LCD_space(2);

                    pntr = 9*l_word;
                    for(cnt=0 ; cnt<=5; cnt++){  // M
                        LCD_data( words[pntr+cnt] );
                    }
                    LCD_data( 'M' );
                    LCD_Setline(line_2);

                    if( rate & 0x02 ){
                        pntr = 4*l_word;
                        for(cnt=0 ; cnt<=10; cnt++){  // E
                            LCD_data( words[pntr+cnt] );
                        }
                        LCD_data( 'E' );
                        LCD_data( ' ' );
                    }
                    else{
                        pntr = 2*l_word;
                        for(cnt=0 ; cnt<=10; cnt++){  // N
                            LCD_data( words[pntr+cnt] );
                        }
                        LCD_data( 'N' );
                        LCD_data( ' ' );
                    }

                    pntr = 7*l_word;
                    for(cnt=0 ; cnt<=1; cnt++){  // S
                        LCD_data( words[pntr+cnt] );
                    }
                    LCD_data( 'S' );
                }
            gps_pntr = 0 ;
            }
        }
    }
}

// Cut down
void cut_down(){
    int16 n;
    int16 w_cnt;            // Counter of word
    int16 word_pntr;        // Pointer of words[]

    w_cnt = word_pntr = 0;
    for( n = 0; n <= gps_max ; n++){
        if( gps[n] == ','){            // 0x2c ','
            w_cnt++;   word_pntr = w_cnt*l_word;
        }
        else{
            words[word_pntr++] = gps[n];
        }
    }
}

// Clear Cut down Area
void clear_words(){
    int16 n;
       for( n = 0; n <= word_max ; n++){
        words[n] = 0x20 ;
    }
}

// ACM1602NI-FLW-FBW-M01
void LCD_Clear_line2(){
    int8 n;
    n = 0;
    LCD_Setline(line_2);
    while(n++ < 16){
        LCD_data(0x20);
    }
}

void LCD_cmd(unsigned char cmd){
    int16 u_t=10;
    i2c_start();        delay_ms(1);
    i2c_write(LCD_ADD); delay_us(u_t);     // Slave Address
    i2c_write(cmd_code);delay_us(u_t);     // Command Mode
    i2c_write(cmd);     delay_us(u_t);     // Send Command
    i2c_stop();         delay_ms(1);
}
void LCD_Clear(){
    LCD_cmd(0x01);
    delay_ms(3);
}
void LCD_Setline(unsigned char line) {
    LCD_cmd(line);
}
void LCD_init(){
    delay_ms(40);
    LCD_cmd(0x01);     //
    delay_ms(1);
    LCD_cmd(0x38);     //
    delay_ms(1);
    LCD_cmd(0x0C);     //
    delay_ms(1);
}
void LCD_data(unsigned char data){
    int16 u_t=10;

    i2c_start();        delay_ms(1);
    i2c_write(LCD_ADD); delay_us(u_t);     // Slave Address
    i2c_write(data_out);delay_us(u_t);     // Data Out Code
    i2c_write(data);    delay_us(u_t);     // Send Command
    i2c_stop();         delay_ms(1);
}
void LCD_space(int8 n){
    int8 cnt;
    cnt = 0;
    while(cnt++ < n){
        LCD_data(' ');
    }
}