daventech TPA81 HELP!!!

[macgyver]

anyone use this unit here is teh cde i am trying to use but cant seem to get it to work. not sure if i am reading it right, any help would be greatly appreicated.

specs of it
http://www.robot-electronics.co.uk/htm/tpa81tech.htm



#include <16F877.H>
#fuses XT, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
#use delay(clock=4000000)
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, ERRORS)
#use i2c(Master, SDA=PIN_C4, SCL=PIN_C3, FORCE_HW)

int8 a1,a2,a3;

void get_temp()
{
i2c_start();
i2c_write(0xD0);
delay_ms(50);
a1 = i2c_read();
a2 = i2c_read();
a3 = i2c_read();
a4 = i2c_read(0);
i2c_stop();
}


void main()
{


while(1)
{

void get_temp();


printf("temp1 = %u\n\r", a1);
printf("temp2 = %u\n\r", a2);
printf("temp3 = %u\n\r", a3);
delay_ms(500);
}

}

[macgyver]

tried

printf("temp1 = %2X\n\r", a1);
printf("temp2 = %2X\n\r", a2);
printf("temp3 = %2X\n\r", a3);

but all i get is FF

[epideath]

Do you have the pull-up resistors attached to the SDA and SCL lines?

You need to read the tutorial under the Connections on the link you had above. It seems that you are missing quite a bit. You need to do a start then send the address and the register you wish to read. Then send another start bit with the address set with the read bit set. so in your case it would be 0xD1 instead of 0xD0. Then you can read the value in the register.

I have never used this unit before so I'm no expert. Just from what I got from reading through it.

Regards

[Guest]

yep got it done, i think i am missing something in the i2c sequence, thanks