Tweaks to temperature code

Marlin/temperature.cpp

@@ -505,7 +505,7 @@ int Temperature::getHeaterPower(int heater) {
 //
 // Temperature Error Handlers
 //
-void Temperature::_temp_error(int e, const char* serial_msg, const char* lcd_msg) {
+void Temperature::_temp_error(const int8_t e, const char * const serial_msg, const char * const lcd_msg) {
   static bool killed = false;
   if (IsRunning()) {
     SERIAL_ERROR_START();
@@ -524,7 +524,7 @@ void Temperature::_temp_error(int e, const char* serial_msg, const char* lcd_msg
   #endif
 }
 
-void Temperature::max_temp_error(int8_t e) {
+void Temperature::max_temp_error(const int8_t e) {
   #if HAS_TEMP_BED
     _temp_error(e, PSTR(MSG_T_MAXTEMP), e >= 0 ? PSTR(MSG_ERR_MAXTEMP) : PSTR(MSG_ERR_MAXTEMP_BED));
   #else
@@ -534,7 +534,7 @@ void Temperature::max_temp_error(int8_t e) {
     #endif
   #endif
 }
-void Temperature::min_temp_error(int8_t e) {
+void Temperature::min_temp_error(const int8_t e) {
   #if HAS_TEMP_BED
     _temp_error(e, PSTR(MSG_T_MINTEMP), e >= 0 ? PSTR(MSG_ERR_MINTEMP) : PSTR(MSG_ERR_MINTEMP_BED));
   #else
@@ -545,7 +545,7 @@ void Temperature::min_temp_error(int8_t e) {
   #endif
 }
 
-float Temperature::get_pid_output(int e) {
+float Temperature::get_pid_output(const int8_t e) {
   #if HOTENDS == 1
     UNUSED(e);
     #define _HOTEND_TEST     true
@@ -890,7 +890,7 @@ float Temperature::analog2temp(int raw, uint8_t e) {
 
 // Derived from RepRap FiveD extruder::getTemperature()
 // For bed temperature measurement.
-float Temperature::analog2tempBed(int raw) {
+float Temperature::analog2tempBed(const int raw) {
   #if ENABLED(BED_USES_THERMISTOR)
     float celsius = 0;
     byte i;
@@ -1292,7 +1292,7 @@ void Temperature::init() {
         SERIAL_EOL();
     */
 
-    int heater_index = heater_id >= 0 ? heater_id : HOTENDS;
+    const int heater_index = heater_id >= 0 ? heater_id : HOTENDS;
 
     #if HEATER_IDLE_HANDLER
       // If the heater idle timeout expires, restart
@@ -1922,7 +1922,7 @@ void Temperature::isr() {
     case SensorsReady: {
       // All sensors have been read. Stay in this state for a few
       // ISRs to save on calls to temp update/checking code below.
-      constexpr int extra_loops = MIN_ADC_ISR_LOOPS - (int)SensorsReady;
+      constexpr int8_t extra_loops = MIN_ADC_ISR_LOOPS - (int8_t)SensorsReady;
       static uint8_t delay_count = 0;
       if (extra_loops > 0) {
         if (delay_count == 0) delay_count = extra_loops;   // Init this delay

Marlin/temperature.h

@@ -535,15 +535,15 @@ class Temperature {
 
     static void checkExtruderAutoFans();
 
-    static float get_pid_output(int e);
+    static float get_pid_output(const int8_t e);
 
     #if ENABLED(PIDTEMPBED)
       static float get_pid_output_bed();
     #endif
 
-    static void _temp_error(int e, const char* serial_msg, const char* lcd_msg);
-    static void min_temp_error(int8_t e);
-    static void max_temp_error(int8_t e);
+    static void _temp_error(const int8_t e, const char * const serial_msg, const char * const lcd_msg);
+    static void min_temp_error(const int8_t e);
+    static void max_temp_error(const int8_t e);
 
     #if ENABLED(THERMAL_PROTECTION_HOTENDS) || HAS_THERMALLY_PROTECTED_BED
 

Marlin/thermistortable_20.h

@@ -23,27 +23,27 @@
 // PT100 with INA826 amp on Ultimaker v2.0 electronics
 // The PT100 in the Ultimaker v2.0 electronics has a high sample value for a high temperature.
 // This does not match the normal thermistor behaviour so we need to set the following defines
-#if (THERMISTORHEATER_0 == 20)
+#if THERMISTORHEATER_0 == 20
   #define HEATER_0_RAW_HI_TEMP 16383
   #define HEATER_0_RAW_LO_TEMP 0
 #endif
-#if (THERMISTORHEATER_1 == 20)
+#if THERMISTORHEATER_1 == 20
   #define HEATER_1_RAW_HI_TEMP 16383
   #define HEATER_1_RAW_LO_TEMP 0
 #endif
-#if (THERMISTORHEATER_2 == 20)
+#if THERMISTORHEATER_2 == 20
   #define HEATER_2_RAW_HI_TEMP 16383
   #define HEATER_2_RAW_LO_TEMP 0
 #endif
-#if (THERMISTORHEATER_3 == 20)
+#if THERMISTORHEATER_3 == 20
   #define HEATER_3_RAW_HI_TEMP 16383
   #define HEATER_3_RAW_LO_TEMP 0
 #endif
-#if (THERMISTORHEATER_4 == 20)
+#if THERMISTORHEATER_4 == 20
   #define HEATER_4_RAW_HI_TEMP 16383
   #define HEATER_4_RAW_LO_TEMP 0
 #endif
-#if (THERMISTORBED == 20)
+#if THERMISTORBED == 20
   #define HEATER_BED_RAW_HI_TEMP 16383
   #define HEATER_BED_RAW_LO_TEMP 0
 #endif