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#ifndef _CAN2040_H
#define _CAN2040_H
#include <stdint.h> // uint32_t
struct can2040_msg {
uint32_t id;
uint32_t dlc;
union {
uint8_t data[8];
uint32_t data32[2];
};
};
enum {
CAN2040_ID_RTR = 1<<30,
CAN2040_ID_EFF = 1<<31,
};
enum {
CAN2040_NOTIFY_RX = 1<<20,
CAN2040_NOTIFY_TX = 1<<21,
CAN2040_NOTIFY_ERROR = 1<<23,
};
struct can2040;
typedef void (*can2040_rx_cb)(struct can2040 *cd, uint32_t notify
, struct can2040_msg *msg);
void can2040_setup(struct can2040 *cd, uint32_t pio_num);
void can2040_callback_config(struct can2040 *cd, can2040_rx_cb rx_cb);
void can2040_start(struct can2040 *cd, uint32_t sys_clock, uint32_t bitrate
, uint32_t gpio_rx, uint32_t gpio_tx);
void can2040_shutdown(struct can2040 *cd);
void can2040_pio_irq_handler(struct can2040 *cd);
int can2040_check_transmit(struct can2040 *cd);
int can2040_transmit(struct can2040 *cd, struct can2040_msg *msg);
/****************************************************************
* Internal definitions
****************************************************************/
struct can2040_bitunstuffer {
uint32_t stuffed_bits, count_stuff;
uint32_t unstuffed_bits, count_unstuff;
};
struct can2040_transmit {
struct can2040_msg msg;
uint32_t crc, stuffed_words, stuffed_data[5];
};
struct can2040 {
// Setup
uint32_t pio_num;
void *pio_hw;
uint32_t gpio_rx, gpio_tx;
can2040_rx_cb rx_cb;
// Bit unstuffing
struct can2040_bitunstuffer unstuf;
uint32_t raw_bit_count;
// Input data state
uint32_t parse_state;
uint32_t parse_crc;
struct can2040_msg parse_msg;
// Reporting
uint32_t report_state;
// Transmits
uint32_t tx_state;
uint32_t tx_pull_pos, tx_push_pos;
struct can2040_transmit tx_queue[4];
};
#endif // can2040.h
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