heart rate monitor pulse oximeter project

flumplogic said:

waqasalamkhan@hotmail.com is the original email but brought back a postmaster failed so I have posted full email on this site. I hope you guys can help.

Hello there, what a site very helpful. I came across your address on https://www.edaboard.com/threads/176611/ , I am also using the 16f877a pic , however my university has not got pic.h file licence so I can not persist in hitech c, i can use sourceboost and mplab which is what we are provided with. Designing the program is going to be just theory not to application. This is because of the time frame i have to order new parts. I basically have a circuit, initially using bright led and phototransistor, to get a a signal ( with resistors in series, 1k6 and 130k ohms respectively) as the light is switched on i want maximum swing when voltage goes low (5V supply) and current goes up as the resistance across the phototransistor decreases and increases. For some reason, I am not getting an expected noisy output signal, instead its very week, if i amply it, there is just more noise (100Hz internal lighting and sunlight). The choice of resistor in series with the phototransistor is based on datasheet (PT4800E0000F) i need the voltage on oscilloscope to drop from 5V close to zero or do i? The bandpass filter gets rid of the dc component and the low pass part rids high frequencies, i want 2.5Hz has cutt off frequency. ( i.e. between 60bpm to 150bpm).

My query is I need help designing code, using a 4MHz crystal, but with sourceboost, this is the code so far that i would need help on before i put it into isis to simulate. This is the problem, translating this into c from hitech, syntax quite similar but not. I i do this then i can put a pulse in there to test it hence displaying bpm on lcd screen.

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Code C - [expand]
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#include // plz include pic . h file here this file is available in hitech
#ifndef _XTAL_FREQ
// Unless specified elsewhere, 4MHz system frequency is assumed
#define _XTAL_FREQ 4000000
#endif
#define rs RD7
#define e RD6
#define lcd_data PORTB
#define buzzer RC1
void beep (void);
void delayms(unsigned int itime);
void blink(void);
void send_config(unsigned char data);
void pulse(void);
void send_char(unsigned char data);
void lcd_goto(unsigned char data);
void lcd_clr(void);
void send_string(const char *s);
void init_lcd(void);
void dis_num(unsigned int data,unsigned char digit);
unsigned int read_an(unsigned char channel);
void prog1(void);
void display(unsigned char c);
unsigned long no=0;
void main (void)
{
TRISA5=0; 
TRISC=0; 
TRISB=0;
TRISD0=1;
TRISD1=0;
TRISD7=0;
TRISD6=0;
TRISD3=0;
init_lcd();
while(1)
{
prog1();
}
 
}
void prog1(void)
{
unsigned int temp1=0,temp2=0;
unsigned char i;
unsigned int hb=1;
while(RD0);
while(!RD0){
hb++;
__delay_ms(1);
}
hb=30000/hb;
lcd_goto(2);
send_string("H.B.R: bpm");
lcd_goto(8);
dis_num(hb,3);
if(hb>87&&RD3==1) //if value of Heart Beat >87 and sound > 85dB
{
beep(); 
lcd_goto(16); 
send_string(" Stay Calm!! "); 
RD3=0; 
}
else if(hb>87)
{
lcd_goto(16);
send_string(" Stay Calm!! "); 
}
else
{
buzzer=0;
lcd_goto(16);
send_string(" Normal :) ");
}
 
}
void delayms(unsigned int itime)
{
for(;itime>0;itime--)
{__delay_ms(1);}
}
 
 
void send_config(unsigned char data) //send lcd configuration 
{
rs=0; //set lcd to configuration mode
lcd_data=data&0xf0; //lcd data port = data
pulse();
lcd_data=(data<<4)&0xf0; pulse(); }
 void pulse(void) {
 e=1; //pulse e to confirm the data 
delayms(1); e=0; delayms(1); }
 void lcd_goto(unsigned char data) //set the location of the lcd cursor 
{ 
//if the given value is (0-15) the //cursor will be at the upper line 
//if the given value is (20-35) the send_config
//cursor will be at the lower line 
//location of the lcd cursor(2X16): 
} 
void lcd_clr(void) //clear the lcd 
{ send_config(0x01); delayms(2); }
 
void send_string(const char *s) 
//send a string to display in the lcd 
{ rs = 1; while (*s)send_char (*s++); } 
void send_char(unsigned char data) //send lcd character 
{ rs =1; __delay_us(40); //set lcd to display mode 
lcd_data=data&0xf0; //lcd data port = data 
pulse(); lcd_data=(data<<4)&0xf0; pulse();
 } 
void init_lcd(void) { 
rs=0;e=0; //command mode 
delayms(10); //delay 10ms
 lcd_data=0x30; //load initial nibble
 pulse(); //Latch initial code 
delayms(5); //delay 5ms 
pulse(); //Latch initial code 
delayms(1); //delay 1ms 
pulse(); //Latch initial code 
lcd_data=0x20; pulse(); //Latch initial code //configure 
lcd send_config(0x28); //Set 4-bit mode, 2 lines 
send_config(0xF); //Switch off display 
send_config(0x01); //Clear Display 
send_config(0x06); //Enable cursor auto increase //
send_config(0x80); //Zero display address 
void dis_num(unsigned int data,unsigned char digit) {
 if(digit>3)
send_char('0'+(data/1000)%10);
if(digit>2)
send_char('0'+(data/100)%10);
if(digit>1)
send_char('0'+(data/10)%10);
if(digit>0)
send_char('0'+(data/1)%10);
}
 
void beep(void) // beep generator
{
buzzer=1;
delayms(300);
buzzer=0;
delayms(200);
buzzer=1;
delayms(300);
buzzer=0;
delayms(200);
buzzer=1;
delayms(300);
buzzer=0;
delayms(200);
buzzer=1;
delayms(300);
buzzer=0;
delayms(200);
buzzer=1;
delayms(300);
buzzer=0;
delayms(200);
 
}

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