nRF52832 TWI communication error with Senirion SHT30-DIS-B

[Hansen Mi]

Dear Nordic Support Team:

software: nRF5_SDK_15.2.0_9412b96

hardware: nRF 52832 DK, Senirion SHT30-DIS-B

error: TWI communication error at sending measurement command of the sensor SHT30

According to the measurement commands of the sensor SHT30, the nRF 52832 DK as the TWI master, writes 0x212D and 0xE000 into the sesnor SHT30.  In the wave shapes from the oscillograph,the command 0xE0000 is right,  the command 0x212D is wrong, and only error at the 2nd byte 0x2D.

ralated program code: 

uint8_t reg[] = {0x21,0x2D};
err_code = nrf_drv_twi_tx(&m_twi_0, 0x44, reg, sizeof(reg), true);

uint8_t reg[] = {0xE0,0x00};
err_code = nrf_drv_twi_tx(&m_twi_0, 0x44, reg, sizeof(reg), true);

However, I used the othe TWI tool to test the sensor with same commands, the measurement results were right. 

To compare the wave shapes, I found out that the interval of error communicaiton by the nRF52832 DK controls is wider than other TWI tool. maybe that is the matter.

Could you tell me how to decrease the interval by nRF SDK function?

Thanks.

[Jørgen Holmefjord]

Hi,

Is there a problem with writing to the sensor, or is it just what your scope reports that is wrong? How have you configured TWI? Are you using TWIM (EasyDMA enabled) or legacy TWI peripheral?

Best regards,
Jørgen

[Hansen Mi]

For my code, it bases the examples\peripheral\twi_sensor project. The TWI configuration and peripherals are right, because there is a  BH1750 sensor in the project, I can get the right measure value from BH1750 sensor by TWI. 

[Jørgen Holmefjord]

Are you testing this on the nRF52-DK? Can you provide the exact project/code you are using, for us to be able to reproduce the issue?

[Hansen Mi]

I found out the trouble. In the sdk_config.h, I set #define TWI0_ENABLED 1, but lost TWI0_USE_EASY_DMA.

#define TWI0_USE_EASY_DM1 1, the trouble has gone. Thanks for your help.