T32CZ20_spi.h

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#ifndef T32CZ20_SPI_H_
#define T32CZ20_SPI_H_
 
#include "tr_hal_platform.h"
 

 
 
#define TR_HAL_NUM_SPI 2
 
// SPI IDs
typedef enum
{
    SPI_0_ID = 0,
    SPI_1_ID = 1,
 
} tr_hal_spi_id_t;

 
// this is used to set the SPI mode
// this enum uses the same values as the chip registers (section 19.4)
typedef enum
{
    TR_HAL_SPI_MODE_NORMAL = 0,
    TR_HAL_SPI_MODE_DUAL   = 2,
    TR_HAL_SPI_MODE_QUAD   = 3,
 
} tr_hal_spi_mode_t;
 
 
// used to set the data transfer amount - 8 bits or 32 bits
// this enum uses the same values as the chip registers (section 19.4)
typedef enum
{
    TR_HAL_SPI_BIT_SIZE_8  = 0x10,
    TR_HAL_SPI_BIT_SIZE_32 = 0x70,
 
} tr_hal_spi_bit_size_t;
 
 
// FIFO sizes - this is a chip limitation
#define TR_HAL_SPI_TX_FIFO_SIZE 32
#define TR_HAL_SPI_RX_FIFO_SIZE 32
 
// for setting the peripheral clock
#define SPI0_CLK_BIT 20
#define SPI1_CLK_BIT 21
#define SPI0_CLK_ENABLE_VALUE 0x100000
#define SPI1_CLK_ENABLE_VALUE 0x200000

 
#define SPI_INVALID_PIN 0xFF
 
// TODO: pick defaults here, these were just picked to avoid LEDs and buttons
#define DEFAULT_SPI_CLK_PIN  22
#define DEFAULT_SPI_CS_PIN   23
#define DEFAULT_SPI_IO_0_PIN 28
#define DEFAULT_SPI_IO_1_PIN 29
 

#ifdef QSPI0_SECURE_EN
    #define CHIP_MEMORY_MAP_SPI0_BASE     (0x50020000UL)
#else
    #define CHIP_MEMORY_MAP_SPI0_BASE     (0x40020000UL)
#endif //QSPI0_SECURE_EN
 
#ifdef QSPI1_SECURE_EN
    #define CHIP_MEMORY_MAP_SPI1_BASE     (0x50021000UL)
#else
    #define CHIP_MEMORY_MAP_SPI1_BASE     (0x40021000UL)
#endif //QSPI1_SECURE_EN
 
 

typedef struct
{
    // when sending data, write it here
    __IO  uint32_t   spi_tx_data;                // 0x00
 
    // received data comes in from this register
    __I   uint32_t   spi_rx_data;                // 0x04
 
    // configuration of SPI peripheral, incl Controller/Peripheral setting
    __IO  uint32_t   spi_control;                // 0x08
    __IO  uint32_t   spi_aux_control;            // 0x0C
 
    // in Controller mode, configure the CS pins
    __IO  uint32_t   peripheral_select;          // 0x10
 
    // this is used to change the Controller's clock to a different frequency
    // normally it is 32 MHz, but this can bring it down to 16 Mhz, 8, 5.33, 4, etc
    __IO  uint32_t   controller_clock_divider;   // 0x14
 
    // TODO: this is not documented, look into it
    __IO  uint32_t   epd_function;               // 0x18
 
    // if running as SPI Controller: configure delay
    __IO  uint32_t   controller_delay_setting;   // 0x1C
 
    // interrupt enable/status/clear
    __IO  uint32_t   interrupt_enable;           // 0x20
    __I   uint32_t   interrupt_status;           // 0x24
    __IO  uint32_t   interrupt_clear;            // 0x28
 
    // enable and disable the SPI peripheral
    __IO  uint32_t   spi_enable_disable;         // 0x2C
 
    // status of SPI peripheral
    __I   uint32_t   spi_status;                 // 0x30
 
    // can read the current levels of the TX and RX FIFOs
    __I   uint32_t   tx_fifo_current_level;      // 0x34
    __I   uint32_t   rx_fifo_current_level;      // 0x38
 
    // reserved space
    __I   uint32_t   reserved_1;                 // 0x3C
 
    // setup for DMA receive
    __IO  uint32_t   DMA_rx_buffer_addr;         // 0x40
    __IO  uint32_t   DMA_rx_buffer_len;          // 0x44
 
    // setup for DMA transmit
    __IO  uint32_t   DMA_tx_buffer_addr;         // 0x48
    __IO  uint32_t   DMA_tx_buffer_len;          // 0x4C
 
    __I   uint32_t   DMA_rx_xfer_len_remaining;  // 0x50
    __I   uint32_t   DMA_tx_xfer_len_remaining;  // 0x54
 
    // using DMA - interrupt enable, status, and DMA RX start and DMA TX start
    __IO  uint32_t   DMA_interrupt_enable;       // 0x58
    __IO  uint32_t   DMA_interrupt_status;       // 0x5C
    __IO  uint32_t   DMA_rx_enable;              // 0x60
    __IO  uint32_t   DMA_tx_enable;              // 0x64
 
} SPI_REGISTERS_T;
 
 
// *****************************************************************
// this orients the SPIx_REGISTERS struct with the correct addresses
// so referencing a field will now read/write the correct SPI
// register chip address
#define SPI0_REGISTERS  ((SPI_REGISTERS_T *) CHIP_MEMORY_MAP_SPI0_BASE)
#define SPI1_REGISTERS  ((SPI_REGISTERS_T *) CHIP_MEMORY_MAP_SPI1_BASE)
 
// *****************************************************************
// helper defines for SPI STATUS REGISTER (0x30)
#define SPI_STATUS_TX_IN_PROGRESS 0x01
#define SPI_STATUS_TX_FIFO_EMPTY  0x04
#define SPI_STATUS_TX_FIFO_FULL   0x10
#define SPI_STATUS_RX_FIFO_EMPTY  0x20
#define SPI_STATUS_RX_FIFO_FULL   0x80
 
 
// *****************************************************************
// helper defines for SPI CONTROL REGISTER (0x08)
 
// bit 0 = set=controller, clear=peripheral
#define SPI_CONTROL_REG_SET_AS_CONTROLLER   0x01
#define SPI_CONTROL_REG_SET_AS_PERIPHERAL   0x00
// bit 1 = cpha (clock phase)
#define SPI_CONTROL_REG_CPHA_HIGH           0x02
#define SPI_CONTROL_REG_CPHA_LOW            0x00
// bit 2 = cpol (clock polarity)
#define SPI_CONTROL_REG_CPOL_HIGH           0x04
#define SPI_CONTROL_REG_CPOL_LOW            0x00
// bit 3 = sdata0or1, set to 0 for controller and 1 for peripheral
#define SPI_CONTROL_REG_SDATA_FOR_CROSSED   0x08
// bit 4 = byte swap
#define SPI_CONTROL_REG_BYTE_SWAP           0x10
// bit 5 = MSB first
#define SPI_CONTROL_REG_MSB_FIRST           0x20
// bit 6 = continuous transfer
#define SPI_CONTROL_REG_CONTINUOUS_TRANSFER 0x40
// bit 7 = reserved
// bit 8 - pre delay enable
#define SPI_CONTROL_PRE_DELAY_ENABLE        0x100
// bit 9 - inter delay enable
#define SPI_CONTROL_INTER_DELAY_ENABLE      0x200
// bit 10 - post delay enable
#define SPI_CONTROL_POST_DELAY_ENABLE       0x400
// bit 14-15 = txf_th
#define SPI_CONTROL_DMA_THRESHHOLD_4        0x0000
#define SPI_CONTROL_DMA_THRESHHOLD_8        0x4000
#define SPI_CONTROL_DMA_THRESHHOLD_16       0x8000
#define SPI_CONTROL_DMA_THRESHHOLD_24       0xC000
 
 
// *****************************************************************
// helper defines for SPI AUX CONTROL REGISTER (0x0C)
 
// bits 0,1 are SPI MODE
#define SPI_AUX_CTRL_REG_MODE_MASK 0x03
 
// bit 2 = setting this bit prevents transmitting
#define SPI_AUX_CTRL_REG_PREVENT_TX_BIT 0x04
 
// bit 3 = setting this bit prevents receiving
// this can be useful to set when transmitting, so you don't receive
// the bytes you just sent
#define SPI_AUX_CTRL_REG_PREVENT_RX_BIT 0x08
 
// bits 4,5,6 = bitsize
#define SPI_AUX_CTRL_REG_BITSIZE_MASK 0x70
 
// used to extend the transfer, like if using dual SPI mode and
// wanting the Controller to be able to receive
#define SPI_AUX_CTRL_REG_TRANSFER_EXTEND 0x80
 
 
// *****************************************************************
// helper defines for SPI INTERRUPT ENABLE REGISTER (0x20)
// and SPI INTERRUPT STATUS REGISTER (0x24)
// and SPI INTERRUPT CLEAR REGISTER (0x28)
#define SPI_INTERRUPT_TX_EMPTY      0x01
#define SPI_INTERRUPT_RX_FULL       0x08
#define SPI_INTERRUPT_TRANSFER_DONE 0x10
#define SPI_INTERRUPT_RX_NOT_EMPTY  0x20
// all and none
#define SPI_INTERRUPT_ALL           0x39
#define SPI_INTERRUPT_NONE          0x00
 
// *****************************************************************
// helper defines for SPI PERIPHERAL SELECT REGISTER (0x10)
// which CS line to select
#define SPI_PERIPH_SELECT_NONE 0x00
#define SPI_PERIPH_SELECT_0    0x01
#define SPI_PERIPH_SELECT_1    0x02
#define SPI_PERIPH_SELECT_2    0x04
#define SPI_PERIPH_SELECT_3    0x08
// polarity for CS lines
#define SPI_PERIPH_SEL_0_ACTIVE_HIGH 0x100
#define SPI_PERIPH_SEL_0_ACTIVE_LOW  0x000
#define SPI_PERIPH_SEL_1_ACTIVE_HIGH 0x200
#define SPI_PERIPH_SEL_1_ACTIVE_LOW  0x000
#define SPI_PERIPH_SEL_2_ACTIVE_HIGH 0x400
#define SPI_PERIPH_SEL_2_ACTIVE_LOW  0x000
#define SPI_PERIPH_SEL_3_ACTIVE_HIGH 0x800
#define SPI_PERIPH_SEL_3_ACTIVE_LOW  0x000
// if CS is set for manual mode, this controls it
#define SPI_PERIPH_SEL_0_SET_HIGH 0x10000
#define SPI_PERIPH_SEL_0_SET_LOW  0x00000
#define SPI_PERIPH_SEL_1_SET_HIGH 0x20000
#define SPI_PERIPH_SEL_1_SET_LOW  0x00000
#define SPI_PERIPH_SEL_2_SET_HIGH 0x40000
#define SPI_PERIPH_SEL_2_SET_LOW  0x00000
#define SPI_PERIPH_SEL_3_SET_HIGH 0x80000
#define SPI_PERIPH_SEL_3_SET_LOW  0x00000
// these set CS for manual mode
#define SPI_PERIPH_SEL_0_MANUAL_MODE 0x1000000
#define SPI_PERIPH_SEL_1_MANUAL_MODE 0x2000000
#define SPI_PERIPH_SEL_2_MANUAL_MODE 0x4000000
#define SPI_PERIPH_SEL_3_MANUAL_MODE 0x8000000
 
 
 
// *****************************************************************
// helper defines for SPI ENABLE DISABLE REGISTER (0x2C)
#define SPI_ENABLE  0x01
#define SPI_DISABLE 0x00
 
// *****************************************************************
// helper enums for SPI CONTROLLER CLOCK REGISTER (0x14)
// note: this register has two fields that determine clock
// the first field can be OFF (32 MHZ) or ON (bit 8 = 0x100 when set)
// If ON then the 2nd field determines the clock by creating a divider
// for the 32 MHz clock. It uses bits 0 to 7 (a full byte) to determine
// the divider like this: ((setting +1) *2)
// meaning 0  is 0  +1=1  *2 = 2 --> 32 MHz / 2 = 16 MHz
// meaning 1  is 1  +1=2  *2 = 4 --> 32 MHz / 4 =  8 MHz
// meaning 3  is 3  +1=4  *2 = 8 --> 32 MHz / 8 =  4 MHz
// meaning 7  is 7  +1=8  *2 =16 --> 32 MHz / 16=  2 MHz
// meaning 15 is 15 +1=16 *2 =32 --> 32 MHz / 32=  1 MHz
// meaning 31 is 31 +1=32 *2 =64 --> 32 MHz / 64=  500 KHz
// meaning 63 is 63 +1=64 *2 =128--> 32 MHz / 128= 250 KHz
// meaning 127is 127+1=128*2 =256--> 32 MHz / 256= 125 KHz
// etc
// up to 0xFF = 255+1=256*2 = 512 --> 32 MHz / 512 =  1/16th MHz = 62.5 KHz
//
// these enums COMBINES the 2 fields so there is only one enum needed
// to set each clock rate desired in the controller_clock_divider register.
// This set of enums is NOT exhaustive (there would 256)
typedef enum
{
    SPI_CTRL_CLOCK_32_MHZ  = 0x000,
    SPI_CTRL_CLOCK_16_MHZ  = 0x100,
    SPI_CTRL_CLOCK_8_MHZ   = 0x101,
    SPI_CTRL_CLOCK_4_MHZ   = 0x103,
    SPI_CTRL_CLOCK_2_MHZ   = 0x107,
    SPI_CTRL_CLOCK_1_MHZ   = 0x10F,
    SPI_CTRL_CLOCK_500_KHZ = 0x11F,
    SPI_CTRL_CLOCK_250_KHZ = 0x13F,
    SPI_CTRL_CLOCK_125_KHZ = 0x17F,
 
} tr_hal_spi_clock_rate_t;
 
 
// *****************************************************************
// helper defines for SPI DMA INTERRUPT ENABLE REGISTER (0x58)
#define SPI_DMA_INTERRUPTS_DISABLE  0x00
#define SPI_DMA_RX_INTERRUPT_ENABLE 0x01
#define SPI_DMA_TX_INTERRUPT_ENABLE 0x02
 
// *****************************************************************
// helper defines for SPI DMA INTERRUPT STATUS REGISTER (0x5C)
#define SPI_DMA_RX_INTERRUPT_ACTIVE 0x01
#define SPI_DMA_TX_INTERRUPT_ACTIVE 0x02
 
// *****************************************************************
// helper defines for DMA_rx_enable (0x60) and DMA_tx_enable(0x64) REGISTERs
#define SPI_DMA_ENABLE  0x01
#define SPI_DMA_DISABLE 0x00
 
// if using DMA for RX we require a minimum for the buffer
#define SPI_DMA_RX_BUFF_MINIMUM_SIZE 16
 

SPI_REGISTERS_T* tr_hal_spi_get_register_address(tr_hal_spi_id_t spi_id);
 

#define TR_HAL_SPI_EVENT_TX_EMPTY          0x00000001
#define TR_HAL_SPI_EVENT_RX_FULL           0x00000008
#define TR_HAL_SPI_EVENT_RX_HAS_MORE_DATA  0x00000010
#define TR_HAL_SPI_EVENT_TRANSFER_DONE     0x00000020
#define TR_HAL_SPI_EVENT_RX_TO_USER_FX     0x00000040
#define TR_HAL_SPI_EVENT_RX_READY          0x00000080
#define TR_HAL_SPI_EVENT_DMA_RX_TO_USER_FX 0x00000100
#define TR_HAL_SPI_EVENT_DMA_RX_READY      0x00000200
#define TR_HAL_SPI_EVENT_DMA_TX_COMPLETE   0x00000400
 

 
// prototype for callback from the Trident HAL to the app when a byte is received
typedef void (*tr_hal_spi_receive_callback_t) (uint8_t num_received_bytes, uint8_t* byte_buffer);
 
// prototype for callback from the Trident HAL to the app when an event happens
typedef void (*tr_hal_spi_event_callback_t) (tr_hal_spi_id_t spi_id, uint32_t event_bitmask);
 

typedef struct
{
    // **** high level settings ****
 
    // true=SPI Controller, false=SPI Peripheral
    // (maps to bit 5 in CONTROL register, and also controls bit 6)
    bool run_as_controller;
 
    // Normal SPI, Dual SPI, or Quad SPI
    tr_hal_spi_mode_t spi_mode;
 
 
    // **** pins used ****
 
    // pins to use for the SPI
    tr_hal_gpio_pin_t clock_pin;
    // this is also known as SDO
    tr_hal_gpio_pin_t io_0_pin;
    // this is also known as SDI
    tr_hal_gpio_pin_t io_1_pin;
    // ony valid if spi_mode=TR_HAL_SPI_MODE_QUAD
    tr_hal_gpio_pin_t io_2_pin;
    tr_hal_gpio_pin_t io_3_pin;
 
    // chip select - SPI0 can have up to 4
    uint8_t num_chip_select_pins;
    tr_hal_gpio_pin_t chip_select_0;
    tr_hal_gpio_pin_t chip_select_1;
    tr_hal_gpio_pin_t chip_select_2;
    tr_hal_gpio_pin_t chip_select_3;
 
    // C = SPI Controller, P = SPI Peripheral
    // normally, SDO on C is wired to SDO on P, and SDI on C is wired to SDI on P
    // but sometimes these pins are crossed. if the pins are crossed (SDO wired to SDI)
    // then set this option to TRUE. This controls how the value of sdat0or1 in the
    // control register is set. If sdo_sdi_pins_crossed=T and the device is a Peripheral
    // then the sdat0or1 gets set to 1
    bool sdo_sdi_pins_crossed;
 
 
    // **** SPI Clock Settings ****
 
    // NOTE: SPI mode 0 is most common, this is:
    // CPOL = 0
    // CPHA = 0
 
    // (CPOL = CLOCK POLARITY) SPI clock rests high? (maps to bit 4 in CONTROL register)
    // true=clock rests high, false=clock rests low
    bool cpol_bit;
 
    // (CPHA = CLOCK PHASE) first bit on SS (maps to bit 3 in CONTROL register)
    // true=first TX bit as SS is asserted, false=first TX bit on first clk edge after SS
    bool cpha_bit;
 
    // for the Controller only: set the clock speed
    tr_hal_spi_clock_rate_t controller_clock_rate;
 
 
    // **** TX/RX settings ****
 
    // bit size of TX and RX FIFO
    tr_hal_spi_bit_size_t bit_size;
 
    // if this is set to false (0) then chip select deasserts after each byte
    // if this is set to true(1) then chip select STAYS asserted until all bytes are done
    // most SPI devices getting multiple bytes will expect CS to remain asserted
    // only matters when run_as_controller=true (maps to bit 0 in CONTROL register)
    bool continuous_transfer;
 
    // Byte swap in bitsize = 16/32 bit for TX/RX FIFO
    bool byte_swap;
 
    // (MSB/LSB) true=MSB, false=LSB (maps to bit 2 in CONTROL register)
    bool most_significant_bit_first;
 
    // do we enable inter transfer delays
    // only matters when run_as_controller=true (maps to bit 11 in CONTROL register)
    bool enable_inter_transfer_delay;
 
    // if enable_inter_transfer_delay=T, this sets the delay
    uint16_t delay_in_clock_cycles;
 
 
    // **** DMA settings ****
 
    bool     rx_dma_enabled;
    bool     tx_dma_enabled;
    // note: RX buffer must STAY allocated
    uint8_t* rx_dma_buffer;
    uint16_t rx_dma_buff_length;
    // note: TX buffers are passed when transmitting
 
 
    // **** non-DMA transmit ****
 
    // if transmit is not done with DMA, then the app needs to allocate a
    // transmit buffer and set a pointer to that transmit buffer here
    uint8_t* raw_tx_buffer;
    uint16_t raw_tx_buff_length;
 
 
    // **** receive and event handler functions ****
 
    // callback from HAL to App when a byte is received
    // if the app doesn't want this, then set it to NULL
    tr_hal_spi_receive_callback_t rx_handler_function;
 
    // callback from HAL to App when an event happens
    // if the app doesn't want this, then set it to NULL
    tr_hal_spi_event_callback_t  event_handler_fx;
 
 
    // **** chip behavior settings ****
 
 
    // are the chip interrupts enabled?
    bool enable_chip_interrupts;
 
    // set the INT priority
    tr_hal_int_pri_t interrupt_priority;
 
    // when the device is sleeping, we can choose to DISABLE interrupts,
    // or leave them enabled which would allow the device to wake on
    // an interrupt from this peripheral
    bool wake_on_interrupt;
 
} tr_hal_spi_settings_t;
 

 

#define SPI_CONFIG_CONTROLLER_NORMAL_MODE                          \
    {                                                              \
        .run_as_controller = true,                                 \
        .spi_mode = TR_HAL_SPI_MODE_NORMAL,                        \
        .clock_pin = (tr_hal_gpio_pin_t) { DEFAULT_SPI_CLK_PIN },  \
        .io_0_pin = (tr_hal_gpio_pin_t) { DEFAULT_SPI_IO_0_PIN },  \
        .io_1_pin = (tr_hal_gpio_pin_t) { DEFAULT_SPI_IO_1_PIN },  \
        .io_2_pin = (tr_hal_gpio_pin_t) { SPI_INVALID_PIN },       \
        .io_3_pin = (tr_hal_gpio_pin_t) { SPI_INVALID_PIN },       \
        .num_chip_select_pins = 1,                                 \
        .chip_select_0 =  (tr_hal_gpio_pin_t) { DEFAULT_SPI_CS_PIN },\
        .chip_select_1 = (tr_hal_gpio_pin_t) { SPI_INVALID_PIN },  \
        .chip_select_2 = (tr_hal_gpio_pin_t) { SPI_INVALID_PIN },  \
        .chip_select_3 = (tr_hal_gpio_pin_t) { SPI_INVALID_PIN },  \
        .sdo_sdi_pins_crossed = false,                             \
        .cpol_bit = false,                                         \
        .cpha_bit = false,                                         \
        .controller_clock_rate = SPI_CTRL_CLOCK_1_MHZ,             \
        .bit_size = TR_HAL_SPI_BIT_SIZE_8,                         \
        .continuous_transfer = true,                               \
        .byte_swap = false,                                        \
        .most_significant_bit_first = true,                        \
        .enable_inter_transfer_delay = false,                      \
        .delay_in_clock_cycles = 0,                                \
        .rx_dma_enabled = false,                                   \
        .tx_dma_enabled = false,                                   \
        .rx_dma_buffer = NULL,                                     \
        .rx_dma_buff_length = 0,                                   \
        .raw_tx_buffer = NULL,                                     \
        .raw_tx_buff_length = 0,                                   \
        .rx_handler_function = NULL,                               \
        .event_handler_fx = NULL,                                  \
        .enable_chip_interrupts = true,                            \
        .interrupt_priority = TR_HAL_INTERRUPT_PRIORITY_5,         \
        .wake_on_interrupt = false,                                \
    }
 

 
// SPI power on/off - these are called from init and uninit - the app should not need to call these
tr_hal_status_t tr_hal_spi_power_off(tr_hal_spi_id_t spi_id);
 
tr_hal_status_t tr_hal_spi_power_on(tr_hal_spi_id_t spi_id);
 

 
// function for setting the pins for a standard SPI
// this also checks that the pin choices are VALID for that particular SPI
tr_hal_status_t tr_hal_spi_set_standard_pins(tr_hal_spi_id_t   spi_id,
                                             bool              is_controller,
                                             tr_hal_gpio_pin_t clk_pin,
                                             tr_hal_gpio_pin_t chip_select_0_pin,
                                             tr_hal_gpio_pin_t sdo_pin,
                                             tr_hal_gpio_pin_t sdi_pin);
 
// *** Quad SPI mode is not currently supported ***
// function for setting the pins for a quad SPI which requires 2 more pins
// this also checks that the pin choices are VALID for that particular SPI
 
// function for setting additional chip select pins beyond the 1 already set
// either tr_hal_spi_set_standard_pins or ..set_quad_pins needs to have been called
// this also checks that the pin choices are VALID for that particular SPI
tr_hal_status_t tr_hal_spi_set_addl_cs_pins(tr_hal_spi_id_t   spi_id,
                                            uint8_t           num_chip_select,
                                            tr_hal_gpio_pin_t chip_select_1_pin,
                                            tr_hal_gpio_pin_t chip_select_2_pin,
                                            tr_hal_gpio_pin_t chip_select_3_pin);
 

tr_hal_status_t tr_hal_spi_read_stats(tr_hal_spi_id_t spi_id,
                                      uint32_t* transmit_started,
                                      uint32_t* transmit_completed,
                                      uint32_t* bytes_received);
 
tr_hal_status_t tr_hal_spi_clear_tx_busy(tr_hal_spi_id_t spi_id);
 

// *** these APIs are experimental and have not been proven to work ***
// for sending using DUAL mode. start enables contXfer and sets it for dual mode
// stop puts mode and contXfer back. These modifications happen to the AUX CTRL
// register
 

 
 
#endif // T32CZ20_SPI_H_