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console: the thermistor table's geometry is named rather than spelled

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Steps, counts per step, the rail clearance, the sensor window, the Kelvin
offset and the quarter-degree scale were literals the reader had to
re-derive (4, 256, 1019, 273.15, the shift by 2). Each is now a constant the
table, the interpolation and the battery share. The table is byte-identical.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
BlackMarkandClaude Opus 5.5 committed 2026-10-23 21:49:50 +02:00
1 parent 78c9071f0c
commit e44b45dd1e
2 files changed
+45 -28
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test/consteval.cpp
+7 -5
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@@ -43,7 +43,7 @@ static_assert(duty_entry(99) == 100);
// Monotone across the whole table: a warmer reading never asks for less air.
consteval bool curve_rises()
{
for (std::int32_t t = 1; t < 100; ++t) {
for (std::int32_t t = 1; t < static_cast<std::int32_t>(app::curve::detail::table.size()); ++t) {
if (duty_entry(t) < duty_entry(t - 1)) {
return false;
}
@@ -57,23 +57,25 @@ static_assert(curve_rises());
// thermistor's nominal resistance at
// adc = full_scale * nominal / (series + nominal), and the equation's own
// definition puts that count at the nominal temperature.
using app::thermistor::detail::counts_per_step;
using app::thermistor::detail::quarters_entry;
using app::thermistor::detail::steps;
inline constexpr std::int32_t nominal_count =
static_cast<std::int32_t>(app::thermistor::adc_full_scale * app::thermistor::nominal_resistance /
(app::thermistor::series_resistor + app::thermistor::nominal_resistance));
static_assert(quarters_entry(nominal_count / 4) >= 100); // 25.00 C, in quarters
static_assert(quarters_entry(nominal_count / 4 + 1) < 100); // and the step below it
static_assert(quarters_entry(nominal_count / counts_per_step) >= 100); // 25.00 C, in quarters
static_assert(quarters_entry(nominal_count / counts_per_step + 1) < 100); // and the step below it
// Both clamps, at the ends the divider cannot leave.
static_assert(quarters_entry(0) == 125 * 4);
static_assert(quarters_entry(255) == -40 * 4);
static_assert(quarters_entry(steps - 1) == -40 * 4);
// An NTC on this divider falls with the count: more counts is more resistance
// is a colder sensor, over every step of the table.
consteval bool thermistor_falls()
{
for (std::int32_t i = 1; i < 256; ++i) {
for (std::int32_t i = 1; i < steps; ++i) {
if (quarters_entry(i) > quarters_entry(i - 1)) {
return false;
}