Add function to convert bytes to meters

src/lib.rs

@@ -42,11 +42,20 @@ const UP: [u8; 2] = [0x47, 0x00];
 const DOWN: [u8; 2] = [0x46, 0x00];
 const STOP: [u8; 2] = [0xFF, 0x00];
 
-const MIN_HEIGHT: f32 = 0.62;
-const MAX_HEIGHT: f32 = 1.27;
-
-fn bytes_to_meters(bytes: [u8; 4]) -> f32 {
-    0.0
+pub const MIN_HEIGHT: f32 = 0.62;
+pub const MAX_HEIGHT: f32 = 1.27;
+
+/// convert desk response from bytes to meters
+///
+/// ```
+/// assert_eq!(idasen::bytes_to_meters(&[0x64, 0x19, 0x00, 0x00]), idasen::MAX_HEIGHT);
+/// assert_eq!(idasen::bytes_to_meters(&[0x00, 0x00, 0x00, 0x00]), idasen::MIN_HEIGHT);
+/// assert_eq!(idasen::bytes_to_meters(&[0x51, 0x04, 0x00, 0x00]), 0.7305);
+/// assert_eq!(idasen::bytes_to_meters(&[0x08, 0x08, 0x00, 0x00]), 0.8256);
+/// ```
+pub fn bytes_to_meters(bytes: &[u8]) -> f32 {
+    let as_int = ((bytes[1] as u32) << 8) + bytes[0] as u32;
+    (as_int as f32 / 10000.0) + MIN_HEIGHT
 }
 
 pub fn main() -> Vec<Characteristic> {
@@ -96,9 +105,18 @@ pub fn main() -> Vec<Characteristic> {
     println!("{:?}", desk.command(&control_characteristic, &DOWN));
     println!("{:?}", desk.command(&control_characteristic, &STOP));
 
+    for (bytes, value) in test_values {
+        println!(
+            "{:?} = {}, expected: {}",
+            bytes,
+            bytes_to_meters(&bytes),
+            value
+        );
+    }
+
     loop {
         let response = desk.read_by_type(&status_characteristic, status_characteristic.uuid);
-        println!("H: {:?}", response);
+        println!("H: {:?}", bytes_to_meters(&response.unwrap()));
         thread::sleep(Duration::from_secs(1));
     }