Tweet
#define MCP3204_CLK PIN_B0
#define MCP3204_DOUT PIN_B1
#define MCP3204_DIN PIN_B2
#define MCP3204_CS PIN_B3
void adc_init() {
output_high(MCP3204_CS);
}
void write_adc_byte(BYTE data_byte, BYTE number_of_bits) {
BYTE i;
delay_us(2);
for(i=0; i<number_of_bits; ++i) {
output_low(MCP3204_CLK);
if((data_byte & 1)==0)
output_low(MCP3204_DIN);
else
output_high(MCP3204_DIN);
data_byte=data_byte>>1;
delay_us(50);
output_high(MCP3204_CLK);
delay_us(50);
}
}
BYTE read_adc_byte(BYTE number_of_bits) {
BYTE i,data;
data=0;
for(i=0;i<number_of_bits;++i) {
output_low(MCP3204_CLK);
delay_us(50);
shift_left(&data,1,input(MCP3204_DOUT));
output_high(MCP3204_CLK);
delay_us(50);
}
return(data);
}
long int read_analog_mcp(BYTE channel, BYTE mode) {
int l;
long int h;
BYTE ctrl_bits;
delay_us(200);
if(mode!=0)
mode=1;
output_low(MCP3204_CLK);
output_high(MCP3204_DIN);
output_low(MCP3204_CS);
if(channel==1) // Change so MSB of channel #
ctrl_bits=4; // is in LSB place
else if(channel==3)
ctrl_bits=6;
else if(channel==4)
ctrl_bits=1;
else if(channel==6)
ctrl_bits=3;
else
ctrl_bits=channel;
ctrl_bits=ctrl_bits<<1;
if(mode==1) // In single mode
ctrl_bits |= 1;
else // In differential mode
ctrl_bits &= 0xfe;
ctrl_bits=ctrl_bits<<1; // Shift so LSB is start bit
ctrl_bits |= 1;
write_adc_byte( ctrl_bits, 7); // Send the control bits
h=read_adc_byte(4);
l=read_adc_byte(8);
output_high(MCP3204_CS);
return((h<<8)|l);
}
long int read_analog( BYTE channel ) // Auto specifies single mode
{
long int temp;
if(channel<4)
temp=read_analog_mcp( channel, 1);
else
temp=0;
return temp;
}
void convert_to_volts( long int data, char volts[6]) {
BYTE i, d, div_h, div_l;
long int temp,div;
div=4095/5;
if(data>=4090)
data=4095;
for(i=0;i<=4;i++) {
temp=data/div;
volts[i]=(BYTE)temp+'0';
if(i==0) {
volts[1]='.';
i++;
}
temp=div*(BYTE)temp;
data=data-temp;
div=div/10;
}
volts[i]='\0';
}
Tìm hiểu thêm về tkhanh
Comment