port nanosec and finetune to Second Movement

watch-faces/settings/nanosec_face.h

@@ -0,0 +1,108 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2022 Mikhail Svarichevsky https://3.14.by/
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef NANOSEC_FACE_H_
+#define NANOSEC_FACE_H_
+
+/*
+ * NANOSEC face
+ *
+ * The goal of nanosec face is dramatic improvement of SensorWatch accuracy.
+ * Minimum goal is <60 seconds of error per year. Full success is if we can
+ * reach <15 seconds per year (<0.47ppm error).
+ *
+ * Best used in conjunction with the FINETUNE face.
+ *
+ * It implements temperature correction using tempco from datasheet (and
+ * allows to adjust these) and allows to introduce offset fix. Therefore
+ * requires temperature sensor board.
+ *
+ * Most users will need to apply profile 3 ("default") or 2 ("conservative
+ * datasheet"), and tune first parameter "static offset" (as it's different
+ * for every crystal sample).
+ *
+ * Frequency correction is dithered over 31 correction intervals (31x10
+ * minutes or ~5 hours), to allow <0.1ppm correction resolution.
+ *  * 1ppm is 0.0864 sec per day.
+ *  * 0.1ppm is 0.00864 sec per day.
+ *
+ * To stay under 1ppm error you would need calibration of your specific
+ * instance of quartz crystal after some "burn-in" (ideally 1 year).
+ *
+ * Should improve TOTP experience.
+ *
+ * Default funing fork tempco: -0.034 ppm/°C², centered around 25°C
+ * We add optional cubic coefficient, which was measured in practice on my sample.
+ *
+ * Cadence (CD) - how many minutes between corrections. Default 10 minutes.
+ * Every minute might be too much. Every hour - slightly less power
+ * consumption but also less precision.
+ *
+ * Can compensate crystal aging (ppm/year) - but you really should be worrying
+ * about it on second/third years of watch calibration.
+ *
+ * For full usage instructions, please refer to the wiki:
+ *  https://www.sensorwatch.net/docs/watchfaces/nanosec/
+ */
+
+#include "movement.h"
+
+#define nanosec_profile_count 5
+typedef struct {
+    // Correction profiles:
+    // 0 - static hardware correction.
+    // 1 - static correction with dithering.
+    // 2 - datasheet quadratic correction (universal).
+    // 3 - cubic correction conservative (likely universal).
+    // 4 - cubic correction finetuned (sample-specific).
+    int8_t correction_profile;
+    int16_t freq_correction; // Static correction - multiplied by 100
+    int16_t center_temperature; // Multiplied by 100, +25.0 -> +2500
+    int16_t quadratic_tempco; // 0.034 -> 3400, multiplied by 100000. Stored positive, used as negative.
+    int16_t cubic_tempco; // default 0, 0.000136 -> 1360, multiplied by 10000000. Stored positive, used positive.
+    int8_t correction_cadence;
+    uint32_t last_correction_time; // Not used at the moment - but will in the future
+    int16_t aging_ppm_pa; // multiplied by 100. Aging per year. 
+} nanosec_state_t;
+
+void nanosec_face_setup(uint8_t watch_face_index, void ** context_ptr);
+void nanosec_face_activate(void *context);
+bool nanosec_face_loop(movement_event_t event, void *context);
+void nanosec_face_resign(void *context);
+movement_watch_face_advisory_t nanosec_face_advise(void *context);
+void nanosec_ui_save(void);
+void nanosec_save(void);
+float nanosec_get_aging(void);
+
+
+#define nanosec_face ((const watch_face_t) { \
+    nanosec_face_setup, \
+    nanosec_face_activate, \
+    nanosec_face_loop, \
+    nanosec_face_resign, \
+    nanosec_face_advise, \
+})
+
+#endif // NANOSEC_FACE_H_
+