Hello Actually I was also facing the same problem but you don't have to change the setting but you have to modify the spidev_test.c program instead of transfer(fd) you have to make two function i.e; transfer(fd, write) and transfer(fd, read) and there you have to provide the value.
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? > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/c0f88260-0cfb-411b-9c71-888d1fb77483%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
