SPI MOSI data echoing on MISO line in Synchronous transfer

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

SPI MOSI data echoing on MISO line in Synchronous transfer

1,083 Views
prabhat_
Contributor III

I am working with S32G274A uP acting as a SPI master. Using NXP's RTD APIs of Spi_Ip_SyncTransmit() for reading the Device Id of the slave which is connected externally to the SPI_0. 
  
I have made sure the connections are proper from the evaluation board running on S32G274A to the slave device which in my case is a BMP280 pressure sensor from Bosch. I am probing the signals on the Oscilloscope for debuginng purpose and parallely debugging the internal "State" structure of the SPI drivers of the RTD. The observations are such that whenever I try to PUSH a data on the TX FIFO through the PUSH register, the data automatically gets echoed on the POP register which is supposed to store the incoming data to the master and further doesn't receive any other data. So basically I am receiving the same data on the MISO line which is being tramsitted to the slave on the MOSI line. 

Attached the oscilloscope image below for reference.

Blue - MISO, Red - MOSI, Yellow - CLK, Green - CSBlue - MISO, Red - MOSI, Yellow - CLK, Green - CS

0 Kudos
Reply
1 Reply

970 Views
nxf92355
NXP Employee
NXP Employee

Hi Prabhat

Hope that you are doing well

sorry for late, did problem solved ?

else can you please check with different i2c slave device rather than BMP280, and let us know

 

Regards ,

Tushar

0 Kudos
Reply