Hi,

I am using BB Black to work with a motion sensor through SPI.

By doing 

*echo BB-SPIDEV0 > /sys/devices/bone_capemgr.9/slots*

I am able to get */dev/spidev1.0* and */dev/spidev1.1,* which are supposed 
to be output and input PIN of SPI0 in mode0. I wire P9 pin 18 and 21, and 
tested spidev_test.c, and I got the expected results.

However,after I wire my sensor PINS of MISO, MOSI, CS, VDD, and GND to BB 
Black's corresponding PINS, and use functions *ioctl(fd, 
SPI_IOC_MESSAGE(1), &tr)*; to read one byte (a known value) from a register 
in the motion sensor, I cannot get what I want. I guess there are some 
settings I may not get them right. 

Can any expert show me what are the proper ways/procedure to
1, read *n* bytes from the sensor starting from a register 
2, write n bytes to the sensor 

In the spidev_test example, I use either */dev/spidev1.0* or 
*/dev/spidev1.1, *I can get the expected result. In my sensor case, which 
device handle shall I use? From the DTS description, spidev1.1 is the 
output PIN. So shall I use spidev1.1 to do writing and then read from 
spidev1.0?

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