spi timing

[idoroseman]

I'm connecting the esp32 to CR95HF via the spi port.
i've noticed there's a bit missing on every transaction. so i dug into the manuals and found there's a cure by changing the SPI_MISO_DELAY_MODE to 2
sure enougth i've added the following line into esp32-hal-spi.c @ spiStopBus()
_spi->dev->ctrl2.miso_delay_mode = 2;
and problem was solved. for future compateblity, i wanted to move the fix to my code and not leave it in the driver code.
i saw you can export spi_t by using SPI.bus() but i get an error
error: invalid use of incomplete type 'spi_t {aka struct spi_struct_t}'
any idea how to fix that ?
thanks

[stickbreaker]

@idoroseman on the incomplete type: verify where spi_struct_t is defined. I have found that the espressif style is to obfuscate HAL structures, In the .h of a library a structure is incompletely defined as:

struct hidden_struct_t;
typedef struct hidden_struct_t hidden_t;

then in the .c the structure is actually fleshed out.

struct hidden_struct_t {
    uint8_t super_secret;
    uint32_t dangerous;
};

This allows a HAL function to be passed a complex structure, and simultaneously preventing direct modification of the structure elements by the app.

if you need direct access to elements of the structure, copy the definition from the .c into your sketch.

Chuck.

[idoroseman]

thanks @stickbreaker it did the trick
for future reference i added the following at the begining of the code

#include "soc/spi_struct.h"
struct spi_struct_t {
    spi_dev_t * dev;
#if !CONFIG_DISABLE_HAL_LOCKS
    xSemaphoreHandle lock;
#endif
    uint8_t num;
};

and then i added to setup()

SPI.begin();
spi_t * _spi;
_spi= SPI.bus();
_spi->dev->ctrl2.miso_delay_mode = 2;

before closing this, maybe there should be a nicer way to change registers inside the driver (but this is beyond my scope)

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[stale]

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