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#define SPI_CS 5
#define SPI_MOSI 23
#define SPI_MISO 19
#define SPI_CLK 18

//Configuration for the SPI bus
spi_bus_config_t buscfg={
.mosi_io_num=SPI_MOSI,
.miso_io_num=SPI_MISO,
.sclk_io_num=SPI_CLK,
.quadwp_io_num = -1,
.quadhd_io_num = -1,
};

//Configuration for the SPI slave interface
spi_slave_interface_config_t slvcfg={
.mode=0,
.spics_io_num=SPI_CS,
.queue_size=3,
.flags=0,
.post_setup_cb=my_post_setup_cb,
.post_trans_cb=my_post_trans_cb
};



//Enable pull-ups on SPI lines so we don't detect rogue pulses when no master is connected.
gpio_set_pull_mode(SPI_MOSI, GPIO_PULLUP_ONLY);
gpio_set_pull_mode(SPI_CLK, GPIO_PULLUP_ONLY);
gpio_set_pull_mode(SPI_CS, GPIO_PULLUP_ONLY);


// for test it was configured with pull_up and pull_down too
gpio_set_pull_mode(SPI_MISO, GPIO_FLOATING);

//Initialize SPI slave interface
ret=spi_slave_initialize(RCV_HOST, &buscfg, &slvcfg, SPI_DMA_DISABLED);