我可以使用箭头运算符 (->) 访问我的联合吗?
Can I access my union using the arrow operator (->)?
我想知道我是否可以在联合中使用箭头运算符,但我无权访问我的构建环境。
假设我有以下联合
union max30205_raw_data {
struct {
uint8_t lsb;
uint8_t msb;
};
struct {
uint16_t magnitude_bits:15;
uint16_t sign_bit:1;
};
uint16_t uwrd;
int16_t swrd;
};
我会按照下面的方式填写union的内容,但是我想知道union成员msb
和lsb
的访问是否正确?
int32_t max30205_read_reg16_WithDefUnion(char reg, max30205_raw_data *p_unionRawData) {
char aux[] = {0,0}
int32_t error;
if (reg == MAX30205_REG_TEMPERATURE || reg == MAX30205_REG_THYST_LOW_TRIP || reg == MAX30205_REG_TOS_HIGH_TRIP) {
error = twi_max30205_read(&myMax30205Instance,max30205Address,reg,&aux,sizeof(aux));
if(error == 0){
p_unionRawData->msb = aux[0];//IS THIS RIGHT IN C?
p_unionRawData->lsb = aux[1];//IS THIS RIGHT IN C?
}
}
return error;
}
我将 max30205_read_reg16_WithDefUnion()
称为
int16_t max30205MeasureTemperatureWithDefUnion(void) {
char regT = MAX30205_REG_TEMPERATURE;
max30205_raw_data rawTemp;
rawTemp.msb = 0;
rawTemp.lsb = 0;
rawTemp.swrd = 0;
int16_t temperatureValue = 0;
if (max30205_read_reg16_WithDefUnion(regT,&rawTemp) ==0)
temperatureValue = rawTemp.swrd;
return temperatureValue;
}
是的。 ->
适用于指向结构的指针和指向联合的指针。
我想知道我是否可以在联合中使用箭头运算符,但我无权访问我的构建环境。
假设我有以下联合
union max30205_raw_data {
struct {
uint8_t lsb;
uint8_t msb;
};
struct {
uint16_t magnitude_bits:15;
uint16_t sign_bit:1;
};
uint16_t uwrd;
int16_t swrd;
};
我会按照下面的方式填写union的内容,但是我想知道union成员msb
和lsb
的访问是否正确?
int32_t max30205_read_reg16_WithDefUnion(char reg, max30205_raw_data *p_unionRawData) {
char aux[] = {0,0}
int32_t error;
if (reg == MAX30205_REG_TEMPERATURE || reg == MAX30205_REG_THYST_LOW_TRIP || reg == MAX30205_REG_TOS_HIGH_TRIP) {
error = twi_max30205_read(&myMax30205Instance,max30205Address,reg,&aux,sizeof(aux));
if(error == 0){
p_unionRawData->msb = aux[0];//IS THIS RIGHT IN C?
p_unionRawData->lsb = aux[1];//IS THIS RIGHT IN C?
}
}
return error;
}
我将 max30205_read_reg16_WithDefUnion()
称为
int16_t max30205MeasureTemperatureWithDefUnion(void) {
char regT = MAX30205_REG_TEMPERATURE;
max30205_raw_data rawTemp;
rawTemp.msb = 0;
rawTemp.lsb = 0;
rawTemp.swrd = 0;
int16_t temperatureValue = 0;
if (max30205_read_reg16_WithDefUnion(regT,&rawTemp) ==0)
temperatureValue = rawTemp.swrd;
return temperatureValue;
}
是的。 ->
适用于指向结构的指针和指向联合的指针。