chap3.c

摩托罗拉Mc6805利程

// Chapter 3 6805 C programs
// Jonathan W. Valvano
// This software accompanies the book,
// Embedded Microcomputer Systems: Real Time Interfacing
// published by Brooks Cole, 1999

// Program 3.1. A software function that outputs to a simple printer.
void Output(unsigned char LETTER) { unsigned short cnt;
    PORT=LETTER;     /* sets Port outputs */
    Pulse();         /* pulses GO */
    for(cnt=0,cnt<10000,cnt++);   /* Wait for 100 ms */
}  

// Program 3.2. A software function that inputs from an A/D.
unsigned char Input(void); { int dummy;
    Pulse();                  /* pulses GO       */
    dummy=1000;               /* Wait for 5us    */
    return(PORT);             /* Read A/D result */
}  

// Program 3.4. Assembly language routines to initialize and output to a printer.
// MC68HC705J1A
void Init(void){
    DDRA=0xFF; // outputs
    DDRB=0x01;
    PORTB=1;} // GO=1
void Out(unsigned char value){
unsigned int n;
    PORTA=value;
    PORTB=0;  // GO=0
    PORTB=1;  // GO=1
    for(n=0;n<40000;n++);}


// Program 3.9. C language routines to initialize and read from an A/D.
// MC68HC705J1A
void Init(void){
    DDRA=0x00; // PortA DATA
    DDRB=0x01; // PB0 GO
    PORTB=0;}  // GO=0
unsigned char In(void){ int n;
    PORTB=1;  // GO=1
    PORTB=0;  // GO=0
    for(n=0;n<1;n++);
    return(PORTA);}

// Program 3.11. C language routines to initialize and read from a keyboard.
// MC68HC705J1A
void Init(void){ // PA7=STROBE
    DDRA=0x00;}  // PA6-0 DATA
unsigned char In(void){ 
    while(PORTA&0x80); 
// wait for PA7=0
    while((PORTA&0x80)==0); 
// wait for PA7=1
    return(PORTA&0x7F);}

// Program 3.13. C language routines to initialize and read from an A/D.
// MC68HC705J1A
void Init(void){ // PB1=DONE in
    DDRB=0x01;   // PB0=GO out
    PORTB=0;     // GO=0
    DDRA=0x00;}  // PA=DATA in
unsigned char In(void){ 
    PORTB=1;     // GO pulse
    PORTB=0;
    while((PORTB&0x02)==0); 
// wait for PB1=1
    return(PORTA);}

// Program 3.16. Handshaking C language routines to initialize and read from a sensor.
/ MC68HC705J1A
void Init(void){ // PB1=READY in
    DDRB=0x01;   // PB0=ACK out
    PORTB=0x01;  // ACK=1
    DDRA=0x00;}  // PA=DATA in
unsigned char In(void){ 
unsigned char data;
    while((PORTB&0x02)==0); 
    PORTB=0;     // ACK=0
    data=PORTA;  // read data
    PORTB=1;     // ACK=1
    while(PORTB&0x02); 
    return(data);}


// Program 3.18. Handshaking C language routines to initialize and write to a printer.
// MC68HC705J1A
void Init(void){ // PB1=READY in
    DDRB=0x01;   // PB0=START out
    PORTB=0x01;  // ACK=1
    DDRA=0xFF;}  // PA=DATA out
void Out(unsigned char data){
    PORTB=0;     // START=0
    PORTA=data;  // write data
    PORTB=1;     // START=1
    while(PORTB&0x02); 
    while((PORTB&0x02)==0);}

// Program 3.20. C language initialization of the DS1620
// MC68HC705J1A
void Init(void){ // PB2=RST=0
    DDRB=0x07;   // PB1=CLK=1
    PORTB=0x03;} // PB0=DQ=1

// Program 3.22. C language helper functions for the DS1620
// MC68HC705J1A
void out8(char code){ int n;
  for(n=0;n<8;n++){
     PORTB &= 0xFD;   // PB1=CLK=0
     if(code&0x01)  
       PORTB |= 0x01; // PB0=DQ=1
     else
       PORTB &= 0xFE; // PB0=DQ=0
     PORTB |= 0x02;   // PB1=CLK=1
     code = code>>1;}}
void start(void){
   PORTB |= 0x04;   // PB2=RST=1
   out8(0xEE);
   PORTD &= 0xFB;}  // PB2=RST=0
void stop(void){
   PORTB |= 0x04;   // PB2=RST=1
   out8(0x22);
   PORTB &= 0xFB;}  // PB2=RST=0

// Program 3.24. C language functions to set the configuration register on the DS1620
// MC68HC705J1A
void config(char data){
   PORTB |= 0x04;   // PB2=RST=1
   out8(0x0C);
   out8(data);
   PORTD &= 0xFB;}  // PB2=RST=0

// Program 3.27. C language functions to set the threshold registers on the DS1620
// MC68HC705J1A
void out9(int code){ int n;
  for(n=0;n<9;n++){
     PORTB &= 0xFD;   // PB1=CLK=0
     if(code&0x01)  
       PORTB |= 0x01; // PB0=DQ=1
     else
       PORTB &= 0xFE; // PB0=DQ=0
     PORTB |= 0x02;   // PB1=CLK=1
     code = code>>1;}}
void WriteTH(int data){
   PORTB |= 0x04;   // PB2=RST=1
   out8(0x01);
   out9(data);
   PORTD &= 0xFB;}  // PB2=RST=0
void WriteTL(int data){
   PORTB |= 0x04;   // PB2=RST=1
   out8(0x02);
   out9(data);
   PORTB &= 0xFB;}  // PB2=RST=0

// Program 3.29. C language functions to read the configuration register on the DS1620
// MC68HC705J1A
unsigned char in8(void){ int n; 
unsigned char result;
  DDRB &= 0xFE; // PB0=DQ input
  for(n=0;n<8;n++){
     PORTB &= 0xFD;   // PB1=CLK=0
     result = result>>1;
     if(PORTB&0x01)  
       result |= 0x80; // PB0=DQ=1
     PORTB |= 0x02;}  // PB1=CLK=1
  DDRB |= 0x01;   // PB0=DQ=output
  return result;}
unsigned char ReadConfig(void){
unsigned char value;
   PORTB |= 0x04;   // PB2=RST=1
   out8(0xAC);
   value=in8();
   PORTD &= 0xFB;   // PB2=RST=0
   return value;}

// Program 3.31. C language 9-bit read helper function for the DS1620
// MC68HC705J1A
unsigned int in9(void){ int n; 
unsigned int result=0;
  DDRB &= 0xFE; // PB0=DQ input
  for(n=0;n<9;n++){
     PORTB &= 0xFD;   // PB1=CLK=0
     result = result>>1;
     if(PORTB&0x01)  
       result |= 0x0100; // PB0=DQ=1
     PORTB |= 0x02;}  // PB1=CLK=1
  DDRB |= 0x01;   // PB0=DQ=output
  return result;}

// Program 3.32. C language functions to read the temperatures from the DS1620
// MC68HC705J1A
unsigned int ReadTH(void){
unsigned int value;
   PORTB |= 0x04;   // PB2=RST=1
   out8(0xA1);
   value=in9();
   PORTD &= 0xFB;   // PB2=RST=0
   return value;}
unsigned int ReadTL(void){
unsigned int value;
   PORTB |= 0x04;   // PB2=RST=1
   out8(0xA2);
   value=in9();
   PORTD &= 0xFB;   // PB2=RST=0
   return value;}
unsigned int ReadT(void){
unsigned int value;
   PORTB |= 0x04;   // PB2=RST=1
   out8(0xAA);
   value=in9();
   PORTD &= 0xFB;   // PB2=RST=0
   return value;}