J722SXH01EVM: Not getting SPI output in PROCESSOR-SDK-LINUX-J722S

Jin Lee

Intellectual 1952 points

Part Number: J722SXH01EVM

Tool/software:

Hi,

Thanks for your help to enable MCSPI0 spidev.

When I build and run the included spidev_test, I get the following:

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root@j722s-evm:/# ./spidev_test -v -D /dev/spidev1.0 -p "HELLOWORLD"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 kHz)
TX | 48 45 4C 4C 4F 57 4F 52 4C 44 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __  |HELLOWORLD|
RX | FF FF FF FF FF FF FF FF FF FF __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __  |..........|
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

root@j722s-evm:/# ./spidev_test -v -D /dev/spidev1.0 -p "HELLOWORLD"
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 kHz)
TX | 48 45 4C 4C 4F 57 4F 52 4C 44 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __  |HELLOWORLD|
RX | FF FF FF FF FF FF FF FF FF FF __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __  |..........|

However, when I connect a logic analyzer to the MOSI pin on the J28 expansion header, no data is actually transmitted.