spi.h

 
#ifndef SPI_H
#define SPI_H
 
#include "stm32f439xx.h"
#include "stdint.h"
#include "stdbool.h"
 
// Macro definitions for pin config literals
//
// clang-format off
 
#define SPI_CONFIG_DEFAULT     \
  SPI_CONFIG_FULLDUPLEX_MASTER
 
// Default configuration for full-duplex master mode
#define SPI_CONFIG_FULLDUPLEX_MASTER \
  (SPI_Config) {                     \
    .CPHA     = SPI_CPHA_SECOND,     \
    .CPOL     = SPI_CPOL1,           \
    .MSTR     = SPI_MASTER,          \
    .BR       = SPI_BR_PCLK8,        \
    .LSBFIRST = SPI_MSB_FIRST,       \
    .SSI      = true,                \
    .SSM      = true,                \
    .RXONLY   = false,               \
    .DFF      = SPI_DFF8,            \
    .CRCNEXT  = false,               \
    .CRCEN    = false,               \
    .BIDIOE   = false,               \
    .BIDIMODE = false                \
  }
// clang-format on


typedef enum {
  SPI_CPHA_FIRST, // Begin data capture on first clock transition
  SPI_CPHA_SECOND // Begin data capture on second clock transition
} SPI_Phase;

typedef enum {
  SPI_CPOL0, // Clock idles low
  SPI_CPOL1  // Clock idles high
} SPI_Polarity;

typedef enum {
  SPI_SLAVE, // Slave configuration
  SPI_MASTER // Master configuration
} SPI_MasterSelect;

typedef enum {
  SPI_BR_PCLK2,   // Pclk/2
  SPI_BR_PCLK4,   // Pclk/4
  SPI_BR_PCLK8,   // Pclk/8
  SPI_BR_PCLK16,  // Pclk/16
  SPI_BR_PCLK32,  // Pclk/32
  SPI_BR_PCLK64,  // Pclk/64
  SPI_BR_PCLK128, // Pclk/128
  SPI_BR_PCLK256, // Pclk/256
} SPI_BaudRate;

typedef enum {
  SPI_DFF8, // 8-bit data frame
  SPI_DFF16 // 16-bit data frame
} SPI_DataFormat;

typedef enum {
  SPI_MSB_FIRST, // Transmit MSB first
  SPI_LSB_FIRST  // Transmit LSB first
} SPI_FrameFormat;

typedef struct {
  SPI_Phase CPHA           : 1; 
  SPI_Polarity CPOL        : 1; 
  SPI_MasterSelect MSTR    : 1; 
  SPI_BaudRate BR          : 3; 
  bool SPE                 : 1; 
  SPI_FrameFormat LSBFIRST : 1; 
  bool SSI                 : 1; 
  bool SSM                 : 1; 
  bool RXONLY              : 1; 
  SPI_DataFormat DFF       : 1; 
  bool CRCNEXT             : 1; 
  bool CRCEN               : 1; 
  bool BIDIOE              : 1; 
  bool BIDIMODE            : 1; 
} SPI_Config;

typedef struct SPI {
  SPI_TypeDef *interface;                             
  SPI_Config config;                                  
  void (*send)(struct SPI *, uint16_t);               
  void (*receive)(struct SPI *, volatile uint16_t *); 
  uint16_t (*transmit)(struct SPI *, uint16_t);       
  void (*updateConfig)(struct SPI *, SPI_Config *);   
} SPI_t;
 
SPI_t SPI_init(SPI_TypeDef *, SPI_Config *);
void SPI_send(SPI_t *, uint16_t);
void SPI_receive(SPI_t *, volatile uint16_t *);
uint16_t SPI_transmit(SPI_t *, uint16_t);
void SPI_updateConfig(SPI_t *, SPI_Config *);

#endif