SHT11 Code Debugging

[YASAS]

I need to read data from SHT11 throw computer parallel port(I'm connect to sensor pin2 to parallel port pin15,14 and sensor pin3 to parallel port pin16.

I downloaded freeBSD program If I convert it into windows platform
but it did not work (Output "Device timed Out !!")

does someone con debug my coding?

Regards,

yasas

My coding----


#include <stdio.h>
#include <dos.h>



#define DeviceTimeout 20
#define ReadTimeout 200


//pin 14 : out: bit 2 of 0x37a
//pin 15 : in: bit 8 of 0x379
//pin 16 : out: bit 4 of 0x37a

int Data(int Level) {
outportb(0x37a,(inportb(0x37a)&4) + 2*(!Level));
delay(1*1000);

return (inportb(0x379)&8)==8;
}

void Clock(int Level) {
outportb(0x37a,(inportb(0x37a)&2) + 4*Level);
delay(1*1000);
}



void Bus_Init(void) {
int Cnt;

//Initiate bus
outportb(0x378,0xff);
Data(1);
Clock(1);

//Connection reset sequence
for (Cnt=0; Cnt<9; Cnt++) {
Clock(0);
Clock(1);
}
}



int Bus_Read(unsigned char Command) {
int Cnt;
int Time;
int ReadData;


//Transmission start
Clock(1);
Data(0);
Clock(0);
Clock(1);
Data(1);
Clock(0);


//Send address & command
for (Cnt=0; Cnt<8; Cnt++) {
if (((Command >> (7-Cnt))&1)==1)
Data(1);
else
Data(0);

Clock(1);
Clock(0);
}


//ACK
Data(1);
Clock(1);

Time=0;
while ((Data(1)==1) && (Time++<DeviceTimeout))
delay(1*1000);
if (Time>DeviceTimeout)
printf("Device timed out!!!%c\n",0x07);

Clock(0);


//Wait for the SHT11 to get it's data ready
Time=0;
while ((Data(1)==1) && (Time++<ReadTimeout))
delay(1*1000);
if (Time>ReadTimeout)
printf("Measurement timed out!!!%c\n",0x07);


//Now clock 2 bytes of data in...
ReadData=0;

for (Cnt=0; Cnt<8; Cnt++) {
Clock(1);

ReadData<<=1;
if (Data(1)==1)
ReadData|=1;

Clock(0);
}
//ACK
Data(0);
Clock(1);
Clock(0);
Data(1);

for (Cnt=0; Cnt<8; Cnt++) {
Clock(1);

ReadData<<=1;
if (Data(1)==1)
ReadData|=1;

Clock(0);
}
//!ACK
Data(1);
Clock(1);
Clock(0);

return ReadData;
}



#define Cmd_ReadTemp 0x03
#define Cmd_ReadHum 0x05




int main(void)
{
//FILE *IO = fopen("G:\progport\a\io.txt","r");

int TempData;
int HumData;

float Temp;
float Humidity;


/*if (IO==NULL) {
printf("could not open /dev/io");
}*/


Bus_Init();

TempData=Bus_Read(Cmd_ReadTemp);
HumData=Bus_Read(Cmd_ReadHum);

Temp=TempData*0.01-40.0;
Humidity=-4.0 + 0.0405*HumData - 2.8*HumData*HumData/1000000;

printf("temp: %.2f hum: %.2f\n",Temp,Humidity);

//fclose(IO);


return 0;
}

[jds-pic]

[Haplo]

Your code is converted from FreeBSD, it contains a lot of outportb() and inportb() function calls. I'm not sure if Windows allows reading/writing to the ports directly. You program will probably work fine under pure DOS.

The best way for you to solve this is probably to search Google for a parallel port OCX for Visual basic. I know a couple of free ones are around. They should allow you to read/write the port easily.

http://rspsoftware.clic3.net/rspppc.htm