#include "nbm.h"
/* other includes */

/* nbm global in this demo */
struct NbmDevice nbm;
extern I2C_HandleTypeDef hi2c;

bool user_impl_write_bytes_fcn(uint8_t i2c_addr, uint8_t reg, const uint8_t *value, uint8_t len) {
    // prototype:  HAL_I2C_Mem_Write(I2C_HandleTypeDef *hi2c, uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize, uint8_t* pData, uint16_t Size, uint32_t Timeout) 	
    return (bool) HAL_I2C_Mem_Write(*hi2c, i2c_addr, MemAddSize, value, len, HAL_MAX_DELAY);
}

bool user_impl_read_bytes_fcn(uint8_t i2c_addr, uint8_t reg, uint8_t *value, uint8_t len) {
    // prototype:  HAL_I2C_Mem_Read(I2C_HandleTypeDef *hi2c, uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize, uint8_t* pData, uint16_t Size, uint32_t Timeout) 	
    return (bool) HAL_I2C_Mem_Read(*hi2c, i2c_addr, reg, MemAddSize, value, len, HAL_MAX_DELAY);
}

void error_handler(uint8_t nbm_errno) {
    /* content as you wish, its optional anyway */
    while(1) {
      asm("nop");
    }
}

int main() {
    uint8 nbm_misc_val;
    uint32_t nbm_chenergy_val;
    ...
    /* setup your peripherals, specificically clocks, and hi2c */
    hal_init_peripherals(...);
    hal_init_i2c(&hi2c,...);
    ...
    nbm_init(&nbm, NBM5100A, NBM_I2C_ADDR_0x2E, user_impl_write_bytes_fcn, user_impl_read_bytes_fcn, error_handler);
    ...
    nbm_write_field(&nbm, nbm_field_vfix, NBM_VFIX_VAL_3V57); /* vfix now set to 3.57V */
    ...
    nbm_read_field(&nbm, nbm_field_vcap, &nbm_misc_val);
    /* can now lookup nbm_read_val against NBM_VCAP_VAL_xxx defines to get real world voltage */
    ...
    /* some time later */
    nbm_read_field(&nbm, nbm_field_chengy, &nbm_chenergy_val);
    /* save nbm_chenergy in NVM if system going down and you need to keep track of it */
    ...
}