L47x and L48x use 110C as the calibration temp, rest use 130 (#265)

Rename the calibration structs to Low/High instead of 30/130 for clarity
 * 130 makes no sense when L47 uses 110 and Call30 and Cal30 can also
   be easily mistaken at a glance
High constant is conditional on the device product feature

Author: Crzyrndm

src/adc.rs

@@ -15,7 +15,7 @@ use crate::{
     },
     pac,
     rcc::{Enable, Reset, AHB2, CCIPR},
-    signature::{VrefCal, VtempCal130, VtempCal30, VDDA_CALIB_MV},
+    signature::{VrefCal, VtempCalHigh, VtempCalLow, VDDA_CALIB_MV},
 };
 
 use pac::{ADC1, ADC_COMMON};
@@ -201,6 +201,7 @@ impl ADC {
     pub fn enable_temperature(&mut self, delay: &mut impl DelayUs<u32>) -> Temperature {
         self.common.ccr.modify(|_, w| w.ch17sel().set_bit());
 
+        // FIXME: This note from the reference manual is currently not possible
         // rm0351 section 18.4.32 pg580 (L47/L48/L49/L4A models)
         // Note:
         // The sensor has a startup time after waking from power-down mode before it can output VTS
@@ -278,12 +279,14 @@ impl ADC {
     /// Convert a raw sample from the `Temperature` to deg C
     pub fn to_degrees_centigrade(&self, sample: u16) -> f32 {
         let sample = (u32::from(sample) * self.calibrated_vdda) / VDDA_CALIB_MV;
-        (VtempCal130::TEMP_DEGREES - VtempCal30::TEMP_DEGREES) as f32
+        (VtempCalHigh::TEMP_DEGREES - VtempCalLow::TEMP_DEGREES) as f32
             // as signed because RM0351 doesn't specify against this being an
             // inverse relation (which would result in a negative differential)
-            / (VtempCal130::get().read() as i32 - VtempCal30::get().read() as i32) as f32
+            / (VtempCalHigh::get().read() as i32 - VtempCalLow::get().read() as i32) as f32
             // this can definitely be negative so must be done as a signed value
-            * (sample as i32 - VtempCal30::get().read() as i32) as f32
+            * (sample as i32 - VtempCalLow::get().read() as i32) as f32
+            // while it would make sense for this to be `VtempCalLow::TEMP_DEGREES` (which is 30*C),
+            // the RM specifically uses 30*C so this will too
             + 30.0
     }
 

src/signature.rs

@@ -96,10 +96,10 @@ impl VrefCal {
 /// aka TS_CAL1 in reference manual
 #[derive(Debug)]
 #[repr(C)]
-pub struct VtempCal30(u16);
-define_ptr_type!(VtempCal30, 0x1FFF_75A8);
+pub struct VtempCalLow(u16);
+define_ptr_type!(VtempCalLow, 0x1FFF_75A8);
 
-impl VtempCal30 {
+impl VtempCalLow {
     /// aka TS_CAL1_TEMP in reference manual
     pub const TEMP_DEGREES: u16 = 30;
     /// Read calibration value
@@ -112,13 +112,29 @@ impl VtempCal30 {
 /// aka TS_CAL2 in reference manual
 #[derive(Debug)]
 #[repr(C)]
-pub struct VtempCal130(u16);
-define_ptr_type!(VtempCal130, 0x1FFF_75CA);
+pub struct VtempCalHigh(u16);
+define_ptr_type!(VtempCalHigh, 0x1FFF_75CA);
 
-impl VtempCal130 {
+impl VtempCalHigh {
     /// aka TS_CAL2_TEMP in reference manual
     /// Feature gate Required: this is 110 for L47x/L48x, 130 for other L4s according to
     /// https://github.com/STMicroelectronics/STM32CubeL4/blob/5e1553e07706491bd11f4edd304e093b6e4b83a4/Drivers/STM32L4xx_HAL_Driver/Inc/stm32l4xx_ll_adc.h#L352-L356
+
+    // L47/L48
+    #[cfg(any(
+        feature = "stm32l471",
+        feature = "stm32l475",
+        feature = "stm32l476",
+        feature = "stm32l486"
+    ))]
+    pub const TEMP_DEGREES: u16 = 110;
+    // else
+    #[cfg(not(any(
+        feature = "stm32l471",
+        feature = "stm32l475",
+        feature = "stm32l476",
+        feature = "stm32l486"
+    )))]
     pub const TEMP_DEGREES: u16 = 130;
     /// Read calibration value
     pub fn read(&self) -> u16 {