Reading TMP102 sensor data over i2c.

Question

I'm a beginner on embedded field. 
 I am having a nrf51822 development kit & Starter Kit and a mbed HRM1017(including nrf51822).
I tested mbed source code for advertising TMP102 sensor data.
 mbed.org/.../ 
It worked. 
 But I'd like to implement on nrf51822 development kit (pca10005).
but i don't know how to read sensor data over I2C.
I found only ds1624 code. I want TMP102 code. 
 Where should I start from? 
 Below Code didn't worked. 
 #define TMP102_ADDRESS (0x90 << 1)

int main(void)
{
 nrf_gpio_port_dir_set(NRF_GPIO_PORT_SELECT_PORT1, NRF_GPIO_PORT_DIR_OUTPUT);

 if (!twi_master_init())
 {
 nrf_gpio_port_write(NRF_GPIO_PORT_SELECT_PORT1, 0x55);
 while (true) 
 {
 // Do nothing.
 }
 }

while(true)
{ 
 int8_t temperature;
 int8_t temperature_fraction;
 
 uint8_t data_buffer[2];
 //if (twi_master_transfer((uint8_t)TMP102_ADDRESS, 0x00, 1, TWI_DONT_ISSUE_STOP))
 //{
 if (twi_master_transfer(TMP102_ADDRESS | TWI_READ_BIT, data_buffer, 2, TWI_ISSUE_STOP)) 
 {
 temperature = (int8_t)data_buffer[0];
 temperature_fraction = (int8_t)data_buffer[1];
 
 nrf_gpio_port_clear(NRF_GPIO_PORT_SELECT_PORT1, 0x7F);
 nrf_gpio_port_set(NRF_GPIO_PORT_SELECT_PORT1, (uint8_t)temperature);

 }
 nrf_delay_ms(100);
 //}
}
}
 
 In twi config file, I set 24pin, 25pin.
and I connected 24pin, 25pin, Vext, GND of NRF6310 to SCL, SDA, VCC, GNF of TMP102.

Janek Mann · Accepted Answer

You can use the twi_master library provided in the NRF51 SDK: 
 #define TMP_ADDRESS (0x49 << 1)

void TMP_getdata(uint8_t* data) {
 twi_master_transfer(TMP_ADDRESS | TWI_READ_BIT, data, 2, TWI_ISSUE_STOP);
}
 
 You need to create a file twi_master_config.h with your pin configuration, and add the twi_sw_master.c file to your project, and call twi_master_setup before calling the other twi functions.

Reading TMP102 sensor data over i2c.

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