can_timing.h

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#ifndef RCBENCH_CAN_TIMING_H
#define RCBENCH_CAN_TIMING_H
 
#include <stdbool.h>
#include <stdint.h>
 
#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
    uint32_t clock_hz;   
    uint16_t div_min;    
    uint16_t div_max;
    uint16_t div_step;   
    uint8_t  tseg1_min;  
    uint8_t  tseg1_max;
    uint8_t  tseg2_min;  
    uint8_t  tseg2_max;
    uint8_t  sjw_max;
    uint8_t  tq_min;     
    uint8_t  tq_max;
} can_timing_limits_t;
 
typedef struct {
    uint16_t div;        
    uint8_t  tseg1;
    uint8_t  tseg2;
    uint8_t  sjw;
    uint8_t  tq;         
    uint32_t bitrate_hz; 
    uint16_t sample_permille; 
} can_timing_t;

#define CAN_SAMPLE_POINT_DEFAULT 875

#define CAN_SAMPLE_POINT_LINK 750

bool can_timing_solve(const can_timing_limits_t *lim, uint32_t bitrate,
                      uint16_t target_permille, can_timing_t *out);

uint32_t can_timing_max_bitrate(const can_timing_limits_t *lim);
 
/* ------------------------------------------------- the two controllers */

void can_timing_limits_mcp2515(can_timing_limits_t *out, uint32_t crystal_hz);

void can_timing_limits_twai(can_timing_limits_t *out);
 
/* --------------------------------------------------- MCP2515 registers */
 
#define MCP2515_CNF1 0x2A
#define MCP2515_CNF2 0x29
#define MCP2515_CNF3 0x28

bool mcp2515_encode_timing(const can_timing_t *t, uint8_t cnf[3]);
 
#ifdef __cplusplus
}
#endif
 
#endif /* RCBENCH_CAN_TIMING_H */