#[repr(C)]pub struct phydat_t {
pub val: [i16; 3],
pub unit: u8,
pub scale: i8,
}
Expand description
@brief Generic data structure for expressing physical values
Physical data is expressed in a 3-dimensional tuple of values. In addition to the data fields, this struct contains further the (physical) unit and the scale factor of the data. The unit is expressed as constant. The scale factor is expressed as power of 10 (10^factor).
The combination of signed 16-bit numbers with and the scale factor gives us a very high dynamic range (from -3210^-131 to 3210^130). In a wider sense we are saving the values as fixed floating points…
The scale factor is identical for all 3 values.
In a traditional (scientific) computational system the obvious choice for the used data type would be to use floats. We are however on heavily resource constrained (even 8-bit) embedded systems, so we use int16_t here. As most sensor are in some way ADC based, they normally do not use a higher accuracy than 12-14bit, so using 16-bit integers to represent this data is good enough in most cases.
Fields§
§val: [i16; 3]
< the 3 generic dimensions of data
unit: u8
< the (physical) unit of the data
scale: i8
< the scale factor, 10^scale
Trait Implementations§
impl Copy for phydat_t
Auto Trait Implementations§
impl Freeze for phydat_t
impl RefUnwindSafe for phydat_t
impl Send for phydat_t
impl Sync for phydat_t
impl Unpin for phydat_t
impl UnwindSafe for phydat_t
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)Layout§
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...)
attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.
Size: 8 bytes