IWR1843: Error when running SPI loopback test in SDK 3.5

Hi,

I tried to run SPI loopback test in SDK 3.5 with below change. Then I rebuild the test.

C:\ti\mmwave_sdk_03_05_00_04\packages\ti\drivers\spi\test\xwr18xx\main.c

/* Test case global variables */
bool gXWR1xxxLoopbackTest = true;
bool gXWR1xxxSlaveReady = false;

/* Test with MSP43x */
bool gXWR1xxxMasterWithMSPTest = false;
bool gXWR1xxxSlaveWithMSPTest = false;

/* Test with PC through FTDI */
bool gXWR1xxxSlaveWithFTDITest = false;

/* Test with XWR1xxx */
bool gXWR1xxxMasterWithXWR1xxx = false;
bool gXWR1xxxSlaveWithXWR1xxx  = false;

But after I run the spi test, I got below error when doing Test_spiLoopback.

Error: SPI_transfer is successful with incorrect data(0xff), length = 128
Error: SPI_transfer is successful with incorrect data(0xff), length = 126

Pls find full log below. I also tried to rebuild the lib and rebuild the test and got same error.

spi_loopback_error_log.txt

Would you pls kindly advise what I missed?