Subversion Repositories usb_nand_reader

#include "NandDataLine.h"

/* NAND data line */

sbit nand_b0 at LATE2_bit;

sbit nand_b1 at LATE3_bit;

sbit nand_b2 at LATG7_bit;

sbit nand_b3 at LATG8_bit;

sbit nand_b4 at LATF5_bit;

sbit nand_b5 at LATF4_bit;

sbit nand_b6 at LATE4_bit;

sbit nand_b7 at LATE5_bit;

void init_nand_data_line()

{

     TRISE = 0;

     TRISF = 0;

     TRISG = 0;

     LATE = 0;

     LATF = 0;

     LATG = 0;

     nand_b0 = 0;

     nand_b1 = 0;

     nand_b2 = 0;

     nand_b3 = 0;

     nand_b4 = 0;

     nand_b5 = 0;

     nand_b6 = 0;

     nand_b7 = 0;

}

int data_line_last_op = NAND_LAST_OP_NONE;

void data_line_write_byte(unsigned char b)

{

     if(data_line_last_op != NAND_LAST_OP_WRITE)

     {

       TRISE2_bit = 0; TRISE3_bit = 0; TRISE4_bit = 0; TRISE5_bit = 0;

       TRISF4_bit = 0; TRISF5_bit = 0;

       TRISG7_bit = 0; TRISG8_bit = 0;

       data_line_last_op = NAND_LAST_OP_WRITE;

     }

     nand_b0 = (b) & 1;

     nand_b1 = (b >> 1) & 1;

     nand_b2 = (b >> 2) & 1;

     nand_b3 = (b >> 3) & 1;

     nand_b4 = (b >> 4) & 1;

     nand_b5 = (b >> 5) & 1;

     nand_b6 = (b >> 6) & 1;

     nand_b7 = (b >> 7) & 1;

     asm NOP;

     asm NOP;

     asm NOP;

}

unsigned char data_line_read_byte()

{

     unsigned char d = 0;

     if(data_line_last_op != NAND_LAST_OP_READ)

     {

       TRISE2_bit = 1; TRISE3_bit = 1; TRISE4_bit = 1; TRISE5_bit = 1;

       TRISF4_bit = 1; TRISF5_bit = 1;

       TRISG7_bit = 1; TRISG8_bit = 1;

       data_line_last_op = NAND_LAST_OP_READ;

     }

     d |= (unsigned char)PORTE.B2;//nand_b0;

     d |= ((unsigned char)PORTE.B3 << 1);//nand_b1 << 1);

     d |= ((unsigned char)PORTG.B7 << 2);//nand_b2 << 2);

     d |= ((unsigned char)PORTG.B8 << 3);//nand_b3 << 3);

     d |= ((unsigned char)PORTF.B5 << 4);//nand_b4 << 4);

     d |= ((unsigned char)PORTF.B4 << 5);//nand_b5 << 5);

     d |= ((unsigned char)PORTE.B4 << 6);//nand_b6 << 6);

     d |= ((unsigned char)PORTE.B5 << 7);//nand_b7 << 7);

     return d;

}