[SPI] problem with command phase

[michprev]

Hi,
I've been having quite a hard time figguring out why command phase in my SPI driver does not work. Eventually I discovered that it does not work with this code:

Code: Select all

target_device->user2.usr_command_bitlen = 15;
target_device->user2.usr_command_value = 0xA1B2;
target_device->user.usr_command = 1;

// start user command
target_device->cmd.usr = 1;

But works with this code (command length set after command value):

Code: Select all

target_device->user2.usr_command_value = 0xA1B2;
target_device->user2.usr_command_bitlen = 15;
target_device->user.usr_command = 1;

// start user command
target_device->cmd.usr = 1;

I also noticed that ESP-IDF uses this order (which does not work for me too):

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target_device->user2.usr_command_bitlen = 15;
target_device->user.usr_command = 1;
target_device->user2.usr_command_value = 0xA1B2;

// start user command
target_device->cmd.usr = 1;

So I am a bit confused. Anyone knows what is going on?