Hi,
Is it possible the device is physically connected to B56 pin instead of E55 pin? And please check if CS0 has signal in the loopback test:
- Connect MOSI of SPI1 to MISO
- Execute $ sudo modprobe spidev
- Download/build this test file:
https://raw.githubusercontent.com/torvalds/linux/v4.9/tools/spi/spidev_test.c - Run the command and check if the result is expected:
$ sudo ./spidev_test -D /dev/spidev0.0 -v
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
TX | FF FF FF FF FF FF 40 00 00 00 00 95 FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF F0 0D | ......@.......................
RX | FF FF FF FF FF FF 40 00 00 00 00 95 FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF F0 0D | ......@.......................
or
$ sudo ./spidev_test -D /dev/spidev0.0 -v -p "HelloWorld123456789abcdef"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
TX | 48 65 6C 6C 6F 57 6F 72 6C 64 31 32 33 34 35 36 37 38 39 61 62 63 64 65 66 __ __ __ __ __ __ __ | HelloWorld123456789abcdef
RX | 48 65 6C 6C 6F 57 6F 72 6C 64 31 32 33 34 35 36 37 38 39 61 62 63 64 65 66 __ __ __ __ __ __ __ | HelloWorld123456789abcdef
- Check signal of CS0 port while doing step 4.