74hc595 16f877a interfacing problems

milan.rajik · Mar 25, 2015

In this code assign the correct 6 bit and 8 bit MSB and LSB values to vale12send and vale22send variables.

Code C - [expand]
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sbit SH_CP at RD0_bit;
sbit SH_CP_Direction at TRISD0_bit;
 
sbit ST_CP at RD2_bit;
sbit ST_CP_Direction at TRISD2_bit;
 
sbit DS at RD1_bit;
sbit DS_Direction at TRISD1_bit;
 
char uart_rd;
unsigned char value12hc595 = 0, value22hc595 = 0;
 
void interrupt() {
     if(RCIF_bit) {
           if(OERR_bit) {
                 CREN_bit = 0;
                 CREN_bit = 1;
                 
                 OERR_bit = 0;
           }
           uart_rd = UART1_Read();
           RCIF_bit = 0;
     }
}
 
void SPI_Send(unsigned char s1, unsigned char s2) {
     unsigned long mask;
     char i = 0;
     
     mask = 0x20;
     
     for(i = 0; i < 6; i++, mask >>= 1) {
           if(s1 & mask)
               DS = 1;          
           else 
               DS = 0;
               
           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }
     
     for(i = 0; i < 36; i++) {
           DS = 1;
           
           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }
     
     mask = 0x80;
     
     for(i = 0; i < 8; i++, mask >>= 1) {
           if(s2 & mask)
               DS = 1;
           else
               DS = 0;
 
           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }
     
     ST_CP = 1;
     Delay_ms(5);
     ST_CP = 0;
}
 
void main() {
 
     CMCON = 0x07;
     ADCON1 = 0x87;
     
     TRISA = 0xC0;
     TRISB = 0x00;
     TRISC = 0x80;
     TRISD = 0x00;
     
     PORTA = 0x00;
     PORTB = 0x00;
     PORTC = 0x00;
     PORTD = 0x00;
     
     SH_CP_Direction = 0;    
     SH_CP = 0;     
 
     ST_CP_Direction = 0;    
     ST_CP = 0;
     
     DS_Direction = 0;
     DS = 0;
     
     UART1_Init(9615);
     Delay_ms(200);
     
     RCIF_bit = 0;
     RCIE_bit = 1;
     PEIE_bit = 1;
     GIE_bit = 1;
     
     while(1) {
 
          if(uart_rd) {
          
                  switch(uart_rd) {
                  
                        case 'a':
                             value12hc595 = 0b100000;
                             value22hc595 = 0b10000000;
                             break;
                        case 'b':
                             value12hc595 = 0b101000;
                             value22hc595 = 0b01000000;
                             break;
                        case 'c':
                             value12hc595 = 0b110000;
                             value22hc595 = 0b00100000;
                             break;
                        case 'd':
                             value12hc595 = 0b110100;
                             value22hc595 = 0b00010000;
                             break;
                        case 'e':
                             value12hc595 = 0b100100;
                             value22hc595 = 0b00001000;
                             break;
                        case 'f':
                             value12hc595 = 0b111000;
                             value22hc595 = 0b00000100;
                             break;
                        case 'g':
                             value12hc595 = 0b111100;
                             value22hc595 = 0b00000010;
                             break;
                        case 'h':
                             value12hc595 = 0b101100;
                             value22hc595 = 0b00000001;
                             break;
                        case 'i':
                             value12hc595 = 0b011000;
                             value22hc595 = 0b11000000;
                             break;
                        case 'j':
                             value12hc595 = 0b011000;
                             value22hc595 = 0b01100000;
                             break;
                        case 'k':
                             value12hc595 = 0b100010;
                             value22hc595 = 0b00110000;
                             break;
                        case 'l':
                             value12hc595 = 0b101010;
                             value22hc595 = 0b00011000;
                             break;
                        case 'm':
                             value12hc595 = 0b110010;
                             value22hc595 = 0b00001100;
                             break;
                        case 'n':
                             value12hc595 = 0b110110;
                             value22hc595 = 0b00000110;
                             break;
                        case 'o':
                             value12hc595 = 0b100110;
                             value22hc595 = 0b00000011;
                             break;
                        case 'p':
                             value12hc595 = 0b111010;
                             value22hc595 = 0b10000001;
                             break;
                        case 'q':
                             value12hc595 = 0b111110;
                             value22hc595 = 0b11100000;
                             break;
                        case 'r':
                             value12hc595 = 0b101110;
                             value22hc595 = 0b01110000;
                             break;
                        case 's':
                             value12hc595 = 0b011010;
                             value22hc595 = 0b00111000;
                             break;
                        case 't':
                             value12hc595 = 0b011110;
                             value22hc595 = 0b00011100;
                             break;
                        case 'u':
                             value12hc595 = 0b100011;
                             value22hc595 = 0b00001110;
                             break;
                        case 'v':
                             value12hc595 = 0b101011;
                             value22hc595 = 0b00000111;
                             break;
                        case 'w':
                             value12hc595 = 0b011101;
                             value22hc595 = 0b10000011;
                             break;
                        case 'x':
                             value12hc595 = 0b110011;
                             value22hc595 = 0b11000001;
                             break;
                        case 'y':
                             value12hc595 = 0b110111;
                             value22hc595 = 0b11110000;
                             break;
                        case 'z':
                             value12hc595 = 0b101110;
                             value22hc595 = 0b01111000;
                             break;
                        case '0':
                             value12hc595 = 0b011100;
                             value22hc595 = 0b00111100;
                             break;
                        case '1':
                             value12hc595 = 0b100000;
                             value22hc595 = 0b00011110;
                             break;
                        case '2':
                             value12hc595 = 0b101000;
                             value22hc595 = 0b00001111;
                             break;
                        case '3':
                             value12hc595 = 0b110000;
                             value22hc595 = 0b10000111;
                             break;
                        case '4':
                             value12hc595 = 0b110100;
                             value22hc595 = 0b11000011;
                             break;
                        case '5':
                             value12hc595 = 0b100100;
                             value22hc595 = 0b11100001;
                             break;
                  }
                  
                  SPI_Send(value12hc595, value22hc595);
                  uart_rd = 0;
          }
     }
}

varunme · Mar 25, 2015

IN words the below portion is different, it is not dummy values

Code:

     for(i = 0; i < 36; i++) {
           DS = 1;
           
           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }

milan.rajik · Mar 25, 2015

Yes you can have as many ascii characters you want.

varunme · Mar 25, 2015

ok, but I have to send a binary when a special character is triggered,
but this portion will output only 0 or 1, it is not comparing with the binary we send

milan.rajik · Mar 25, 2015

Explain clearly with an example.

varunme · Mar 25, 2015

In the case of

Code:

29	apple	100000 111010 111010 101011 100100 000000 000000 00011110
30	jocker	011100 100110 111100 100010 100100 101110 000000 00001111
31	honey	101100 100110 110110 100100 110111 000000 000000 10000111
32	eagle	100100 101111 111100 111110 100111 000000 000000 11000011

the portion between the LSB and MSB, is not "all zero" or "all one"
There is some difference in values,

Our previous code write only "all zero" or "all one"

The word processing is not a problem, since i can store in special characters

varunme · Mar 26, 2015

How can we reverse the MSB and LSB? just by doing this?

Code:

sbit SH_CP at RD0_bit;
sbit SH_CP_Direction at TRISD0_bit;

sbit ST_CP at RD2_bit;
sbit ST_CP_Direction at TRISD2_bit;

sbit DS at RD1_bit;
sbit DS_Direction at TRISD1_bit;

char uart_rd;
unsigned char value12hc595 = 0, value22hc595 = 0;

void interrupt() {
     if(RCIF_bit) {
           if(OERR_bit) {
                 CREN_bit = 0;
                 CREN_bit = 1;

                 OERR_bit = 0;
           }
           uart_rd = UART1_Read();
           RCIF_bit = 0;
     }
}

void SPI_Send(unsigned char s1, unsigned char s2) {
     unsigned char mask;
     char i = 0;

          mask = 0x80;

     for(i = 0; i < 8; i++, mask >>= 1) {
           if(s2 & mask)
               DS = 1;
           else
               DS = 0;

           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }
     mask = 0x20;


     DS = 1;

     for(i = 0; i < 36; i++) {
           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }
       mask = 0x20;
              for(i = 0; i < 6; i++, mask >>= 1) {
           if(s1 & mask)
               DS = 1;
           else
               DS = 0;

           SH_CP = 1;
           Delay_ms(5);
           SH_CP = 0;
     }


     ST_CP = 1;
     Delay_ms(5);
     ST_CP = 0;
}

void main() {


     CMCON = 0x07;
     ADCON1 = 0x87;

     TRISA = 0xC0;
     TRISB = 0x00;
     TRISC = 0x80;
     TRISD = 0x00;

     PORTA = 0x00;
     PORTB = 0x00;
     PORTC = 0x00;
     PORTD = 0x00;

     SH_CP_Direction = 0;
     SH_CP = 0;

     ST_CP_Direction = 0;
     ST_CP = 0;

     DS_Direction = 0;
     DS = 0;
      // SPI_Send(0b000000, 0b00000000);
     UART1_Init(9615);
     Delay_ms(200);
      UART1_Write_Text("send characters");

     RCIF_bit = 0;
     RCIE_bit = 1;
     PEIE_bit = 1;
     GIE_bit = 1;

     while(1) {

          if(uart_rd) {

                  switch(uart_rd) {

                        case 'a':
                             value22hc595 = 0b100000;
                             value12hc595 = 0b10000000;
                             break;
                        case 'b':
                             value22hc595 = 0b101000;
                             value12hc595 = 0b01000000;
                             break;
                        case 'c':
                             value22hc595 = 0b110000;
                             value12hc595 = 0b00100000;
                             break;
                        case 'd':
                             value22hc595 = 0b110100;
                             value12hc595 = 0b00010000;
                             break;
                        case 'e':
                             value22hc595 = 0b100100;
                             value12hc595 = 0b00001000;
                             break;
                        case 'f':
                             value22hc595 = 0b111000;
                             value12hc595 = 0b00000100;
                             break;
                        case 'g':
                             value22hc595 = 0b111100;
                             value12hc595 = 0b00000010;
                             break;
                        case 'h':
                             value22hc595 = 0b101100;
                             value12hc595 = 0b00000001;
                             break;
                        case 'i':
                             value22hc595 = 0b011000;
                             value12hc595 = 0b11000000;
                             break;
                        case 'j':
                             value22hc595 = 0b011000;
                             value12hc595 = 0b01100000;
                             break;
                        case 'k':
                             value22hc595 = 0b100010;
                             value12hc595 = 0b00110000;
                             break;
                        case 'l':
                             value22hc595 = 0b101010;
                             value12hc595 = 0b00011000;
                             break;
                        case 'm':
                             value22hc595 = 0b110010;
                             value12hc595 = 0b00001100;
                             break;
                        case 'n':
                             value22hc595 = 0b110110;
                             value12hc595 = 0b00000110;
                             break;
                        case 'o':
                             value22hc595 = 0b100110;
                             value12hc595 = 0b00000011;
                             break;
                        case 'p':
                             value22hc595 = 0b111010;
                             value12hc595 = 0b10000001;
                             break;
                        case 'q':
                             value22hc595 = 0b111110;
                             value12hc595 = 0b11100000;
                             break;
                        case 'r':
                             value22hc595 = 0b101110;
                             value12hc595 = 0b01110000;
                             break;
                        case 's':
                             value22hc595 = 0b011010;
                             value12hc595 = 0b00111000;
                             break;
                        case 't':
                             value22hc595 = 0b011110;
                             value12hc595 = 0b00011100;
                             break;
                        case 'u':
                             value22hc595 = 0b100011;
                             value12hc595 = 0b00001110;
                             break;
                        case 'v':
                             value22hc595 = 0b101011;
                             value12hc595 = 0b00000111;
                             break;
                        case 'w':
                             value22hc595 = 0b011101;
                             value12hc595 = 0b10000011;
                             break;
                        case 'x':
                             value22hc595 = 0b110011;
                             value12hc595 = 0b11000001;
                             break;
                        case 'y':
                             value22hc595 = 0b110111;
                             value12hc595 = 0b11110000;
                             break;
                        case 'z':
                             value22hc595 = 0b101110;
                             value12hc595 = 0b01111000;
                             break;
                        case '0':
                             value22hc595 = 0b011100;
                             value12hc595 = 0b00111100;
                             break;
                        case '1':
                             value22hc595 = 0b100000;
                             value12hc595 = 0b00011110;
                             break;
                        case '2':
                             value22hc595 = 0b101000;
                             value12hc595 = 0b00001111;
                             break;
                        case '3':
                             value22hc595 = 0b110000;
                             value12hc595 = 0b10000111;
                             break;
                        case '4':
                             value22hc595 = 0b110100;
                             value12hc595 = 0b11000011;
                             break;
                        case '5':
                             value22hc595 = 0b100100;
                             value12hc595 = 0b11100001;
                             break;
                  }

                  SPI_Send(value12hc595, value22hc595);
                  uart_rd = 0;
          }
     }
}

- - - Updated - - -

yes, its like that

milan.rajik · Mar 27, 2015

Then a seperate code has to be written which receives single characters like 'a' like "a\r\n" and words like apple like "apple\r\n". Then instead of switch statement, if else if statements have to be used and code has to be written. The SPI_Send() function has also need to be modified.

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74hc595 16f877a interfacing problems

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