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respected
Joined: 16 May 2006
Posts: 95
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| HDC1000 Reading sensor |
 Posted: Thu Jan 08, 2015 3:38 pm |
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This is my arduino code and it works
| Code: |
#include <Wire.h>
long value1;
long value2;
long totalvalue;
float temperature;
void setup(){
Serial.begin(9600);
Wire.begin();
Wire.beginTransmission(0x40);
Wire.write(0x10);
Wire.write(0x00); //
Wire.endTransmission();
}
void loop(){
temp_measure();
Serial.print("\n\r");
Serial.print(temperature);
delay(500);
}
float temp_measure(){
Wire.beginTransmission(0x40);
Wire.write(0x00);
delay(10);
Wire.requestFrom(0x40,2);
value1 = Wire.read(); //
value2 = Wire.read(); //
Wire.endTransmission();
totalvalue =((value1<<8)|value2);
temperature= (totalvalue*0.0025177001953125)-40;
} |
This is PIC code. It doesn't work. It comes data0= 0xff or 0xf7 or different value. But this is not true. It has to be temperature value. Can anyone help me please? Where is mistake?
Thanks
| Code: |
#include <18F46J50.h>
#fuses HSPLL,PLL3,CPUDIV2,NOWDT,NODEBUG
#use delay(clock=24MHz,crystal=12MHz)
#use i2c(master,sda=pin_b5, scl=pin_b4, slow)
#use rs232(baud=115200,parity=N,xmit=PIN_A2, bits=8,stream=USART2)
long totaltemp;
float temperature;
char strstore[20];
void hdc_setup (void)
{
i2c_start();
i2c_write(0x40);
i2c_write(0x80);
i2c_write(0x02);
i2c_write(0x10);
i2c_write(0x00);
i2c_stop();
delay_ms(20);
}
void read_hdc(void)
{
int8 data[2]={0,0};
int i;
i2c_start();
i2c_write(0x80);
i2c_write(0x00);
i2c_write(0x81);
for(i=0;i<2;i++)
{
data[i]=i2c_read();
}
i2c_stop();
totaltemp=make16(data[0],data[1]);
temperature=(totaltemp*0.0025177)-40;
sprintf(strstore,"Temp= %f",temperature);
fputs(strstore,USART2);
delay_ms(250);
}
void main()
{
hdc_setup();
while (TRUE)
{
read_hdc();
} //while
}//main
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Thu Jan 08, 2015 3:57 pm |
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| Quote: | void hdc_setup (void)
{
i2c_start();
i2c_write(0x40);
i2c_write(0x80);
i2c_write(0x02);
i2c_write(0x10);
i2c_write(0x00);
i2c_stop();
delay_ms(20);
}
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Arduino uses 7-bit format for the slave address. CCS uses 8-bit format.
You need to fix the CCS code. If you already did this with the 0x80, then
delete the 0x40 line.
| Quote: |
void read_hdc(void)
{
int8 data[2]={0,0};
int i;
i2c_start();
i2c_write(0x80);
i2c_write(0x00);
i2c_write(0x81);
for(i=0;i<2;i++)
{
data[i]=i2c_read();
}
i2c_stop(); |
The last read needs a NACK. You don't need a for() loop for two reads. |
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respected
Joined: 16 May 2006
Posts: 95
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| Posted: Thu Jan 08, 2015 4:45 pm |
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I deleted 0x40 and i wrote
| Code: |
i2c_start();
i2c_write(0x80);
i2c_write(0x00);
i2c_write(0x81);
data[0]=i2c_read();
data[1]=i2c_read();
i2c_stop();
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but same result |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Thu Jan 08, 2015 5:03 pm |
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You need a NACK on the last read, as shown in bold below:
| Quote: |
data[0]=i2c_read();
data[1]=i2c_read(0);
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respected
Joined: 16 May 2006
Posts: 95
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Fri Jan 09, 2015 12:54 pm |
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| Post a sample of your irregular results. |
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respected
Joined: 16 May 2006
Posts: 95
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| Posted: Fri Jan 09, 2015 2:49 pm |
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22:55:14.856> data0= 255
22:55:14.856> data1= 255
22:55:14.856> temp= 124.99
22:55:15.792> data0= 255
22:55:15.792> data1= 255
22:55:15.792> temp= 124.99
22:55:16.544> data0= 31
22:55:16.544> data1= 31
22:55:16.544> temp= -19.94
22:55:17.292> data0= 0
22:55:17.292> data1= 0
22:55:17.292> temp= -40.00
22:55:18.230> data0= 253
22:55:18.230> data1= 123
22:55:18.230> temp= 123.37
22:55:19.169> data0= 239
22:55:19.169> data1= 95
22:55:19.169> temp= 114.28
22:55:20.045> data0= 63
22:55:20.045> data1= 127
22:55:20.045> temp= 0.92
Serial port terminal screen |
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temtronic
Joined: 01 Jul 2010
Posts: 9247
Location: Greensville,Ontario
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| Posted: Fri Jan 09, 2015 3:07 pm |
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You need to post the program you used to display those results.
That device has a specific setup . Also the last 2 bits are NOT part of the 'math' probably need to have the 14 bits right shifted then the math according to the datasheet.
Jay |
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respected
Joined: 16 May 2006
Posts: 95
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| Posted: Fri Jan 09, 2015 3:11 pm |
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| Code: |
#include <18F46J50.h>
#fuses HSPLL,PLL3,CPUDIV2,NOWDT,NODEBUG
#use delay(clock=24MHz,crystal=12MHz)
#use i2c(master,sda=pin_b5, scl=pin_b4, slow)
#use rs232(baud=115200,parity=N,xmit=PIN_A2, bits=8,stream=USART2)
long totaltemp;
float temperature;
char strstore1[20];
char strstore2[20];
char strstore3[20];
void hdc_setup (void)
{
i2c_start();
// i2c_write(0x40);
i2c_write(0x80);
i2c_write(0x02);
i2c_write(0x10);
i2c_write(0x00);
i2c_stop();
delay_ms(20);
}
void read_hdc(void)
{
int8 data[4]={0,0,0,0};
i2c_start();
i2c_write(0x80);
i2c_write(0x00);
i2c_write(0x81);
data[0]=i2c_read();
data[1]=i2c_read(0);
i2c_stop();
totaltemp=make16(data[0],data[1]);
temperature=(totaltemp*0.0025177)-40;
sprintf(strstore1,"data0= %u",data[0]);
sprintf(strstore2,"data1= %u",data[1]);
sprintf(strstore3,"temp= %f",temperature);
fputs(strstore1,USART2);
fputs(strstore2,USART2);
fputs(strstore3,USART2);
delay_ms(750);
}
void main()
{
hdc_setup();
while (TRUE)
{
read_hdc();
} //while
}//main |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Fri Jan 09, 2015 5:11 pm |
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The HDC1000 has two address pins, ADR0 and ADR1. What connections
do you have to these two pins ?
What is the Vdd voltage on your PIC, on the HDC1000, and on the i2c
pullup resistors ?
What is the value of the i2c pullup resistors ?
What happens if you write a program to read a fixed value from the
hdc1000, such as the manufacturer ID word at address 0xFE ?
The data sheet says the ID word is 0x5449 (on page 14). Do you
always get that word, or do you sometimes get 0xFFFF ? |
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respected
Joined: 16 May 2006
Posts: 95
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| Posted: Sat Jan 10, 2015 4:12 pm |
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I tried with TI Sensor Evaluation Module. and I read codes with logic analyser
for 0x5449 i read
0x80+ack 0xfe+ack 0x81+ack 0x54+ack 0x49+nak
and i wrote pic mcu code
| Code: | i2c_start();
i2c_write(0x80);
i2c_write(0xFE);
i2c_write(0x81);
data[0]=i2c_read();
data[1]=i2c_read(0);
i2c_stop();
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i read code with logic analyser
1. 0x80+ack 0xfe+ack 0x81+ack 0x54+ack 0x48+nak
2. 0x80+ack 0x7f+ack 0x40+ack 0x95+ack 0x11+nak
3. 0x80+ack 0xfe+ack 0x81+ack 0x25+ack 0x82+nak |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Sat Jan 10, 2015 9:59 pm |
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I think there is something fundamentally wrong, such as you are
connecting capacitors to SDA and SCL, or the pullups are the wrong
value, or the power supply is bad.
Post a link to a schematic of your PIC to HDC1000 circuit.
How to post an image on the CCS forum:
Use http://www.postimage.com or http://www.imageshack.com
or some other free image hosting service.
Upload your schematic to that website. Preferably a .JPG file or some
other commonly used image format.
Then post a link to your image here in the forum. |
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respected
Joined: 16 May 2006
Posts: 95
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| Posted: Sun Jan 11, 2015 11:03 am |
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https://imageshack.com/i/f0tyuVnUj
I broke sensor and cpu board. Unfortunately pullup resistors was mcu side.
I added pullup (4K7) and It works now.
I sent code
| Code: |
i2c_start();
i2c_write(0x80);
i2c_write(0xFE);
i2c_write(0x81);
data[0]=i2c_read();
data[1]=i2c_read(0);
i2c_stop();
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answer by sensor
data[0]=84 (0x54)
data[1]=73 (0x49)
Thanks for helping for everyone( especially PCM Programmer)
ADR0 and ADR1 default value is 0(GND)
I added 4K7 pullup registor for DRDYn. Special registers are ok. all of data are true. But temperature data and humidity data are coming 0xff.
I will try to continue.
HDC1000 data sheet says
Data ready, active low, open-drain; requires a pull-up resistor to VDD. If not used tie to GND or no connect.
| Code: |
i2c_start();
i2c_write(0x80);
i2c_write(0x00);
delay_ms(13);// I saw in the logic analyser signal
i2c_write(0x81);
data[0]=i2c_read();
data[1]=i2c_read(0);
i2c_stop(); |
Everyting is OK.
Last edited by respected on Sun Jan 11, 2015 3:40 pm; edited 1 time in total |
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respected
Joined: 16 May 2006
Posts: 95
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| Posted: Sun Jan 11, 2015 3:07 pm |
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This is full code.
| Code: |
#include <18F46J50.h>
#fuses HSPLL,PLL3,CPUDIV2,NOWDT,NODEBUG
#use delay(clock=24MHz,crystal=12MHz)
#use i2c(master,sda=pin_b5, scl=pin_b4, slow=100000)
#use rs232(baud=115200,parity=N,xmit=PIN_A2, bits=8,stream=USART2)
long totaltemp;
float temperature;
char strstore1[20];
char strstore2[20];
char strstore3[20];
void hdc_setup (void)
{
i2c_start();
i2c_write(0x80);
i2c_write(0x02);
i2c_write(0x10);
i2c_write(0x00);
i2c_stop();
delay_ms(20);
}
void read_hdc(void)
{
int8 data[4]={0,0,0,0};
i2c_start();
i2c_write(0x80);
i2c_write(0x00);
delay_ms(13);
i2c_write(0x81);
data[0]=i2c_read();
data[1]=i2c_read(0);
i2c_stop();
totaltemp=make16(data[0],data[1]);
temperature=(totaltemp*0.0025177)-40;
sprintf(strstore1,"data0= %u",data[0]);
sprintf(strstore2,"data1= %u\r\n",data[1]);
sprintf(strstore3,"temp= %f",temperature);
fputs(strstore1,USART2);
fputs(strstore2,USART2);
fputs(strstore3,USART2);
delay_ms(500);
}
void main()
{
hdc_setup();
while (TRUE)
{
read_hdc();
} //while
}//main |
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temtronic
Joined: 01 Jul 2010
Posts: 9247
Location: Greensville,Ontario
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| Posted: Sun Jan 11, 2015 7:43 pm |
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nice to hear you got it 'up and running'.
Yes, I2C does need pullups ! too bad TI put them next to their micro and not the temp/hum sensor. It would have saved you some time BUT you learned a LOT of valuable 'hands on' experience.
jay |
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