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Keep the curve and thermistor comments timeless

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Both headers described the port transformation ("legacy cubic becomes",
"no hand-rolled series needed") rather than what the code is. State the
cubic and the __builtin_log rationale directly.

Co-Authored-By: Claude <noreply@anthropic.com>
This commit is contained in:
BlackMark
2026-07-18 10:10:47 +02:00
parent f17ebd17e5
commit b7a2e50506
2 changed files with 5 additions and 5 deletions
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6
src/curve.hpp
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@@ -5,9 +5,9 @@
#include <libavr/flash.hpp> #include <libavr/flash.hpp>
// The auto-mode fan curve, tabulated at compile time: the legacy cubic // The auto-mode fan curve, tabulated at compile time: a cubic in °C
// (0.002246·x³ − 0.09·x² + 0.91·x, zero below 20 °C) becomes a libavr // (0.002246·x³ − 0.09·x² + 0.91·x, zero below 20 °C) as a flash_table of
// flash_table of duty percent per °C. // duty percent per °C.
namespace app::curve { namespace app::curve {
namespace detail { namespace detail {

4
src/thermistor.hpp
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@@ -21,8 +21,8 @@ namespace detail {
consteval double temperature_of(double adc) consteval double temperature_of(double adc)
{ {
double resistance = series_resistor * adc / (1023.0 - adc); double resistance = series_resistor * adc / (1023.0 - adc);
// __builtin_log constant-folds on the AVR backend, so no runtime libm // __builtin_log constant-folds on the AVR backend, so the table is
// and no hand-rolled series is needed for the compile-time table. // built at compile time with no runtime libm.
double steinhart = __builtin_log(resistance / nominal_resistance) / beta + 1.0 / (nominal_temperature + 273.15); double steinhart = __builtin_log(resistance / nominal_resistance) / beta + 1.0 / (nominal_temperature + 273.15);
return 1.0 / steinhart - 273.15; return 1.0 / steinhart - 273.15;
} }