sweep feature added

App/Services/sweep.h

@@ -0,0 +1,57 @@
+/**
+ * @file sweep.h
+ * @brief Hardware-agnostic periodic staircase sweep between two output codes.
+ *
+ * The output steps from `min_code` up to `max_code` (inclusive) every step
+ * period, then returns to `min_code` and holds it for an extra pause before
+ * the next sweep starts.
+ */
+
+#ifndef SWEEP_H
+#define SWEEP_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/**
+ * @brief Host-supplied sweep parameters.
+ */
+typedef struct sweep_config_t {
+    uint16_t min_code;
+    uint16_t max_code;
+    uint16_t step_code;
+    uint16_t step_period_us;
+    uint16_t pause_ms;
+} sweep_config_t;
+
+/**
+ * @brief Sweep state advanced from the periodic tick interrupt.
+ */
+typedef struct sweep_t {
+    uint8_t enabled;
+    uint16_t min_code;
+    uint16_t max_code;
+    uint16_t step_code;
+    uint32_t step_ticks;
+    uint32_t pause_ticks;
+    uint32_t next_code;
+    uint32_t countdown_ticks;
+} sweep_t;
+
+/**
+ * @brief Validate the configuration and start sweeping from `min_code` on the next tick.
+ *
+ * @return false (sweep left stopped) if bounds, step or period are invalid.
+ */
+bool sweep_start(sweep_t *sweep, const sweep_config_t *config, uint32_t tick_us);
+
+void sweep_stop(sweep_t *sweep);
+
+/**
+ * @brief Advance the sweep by one tick.
+ *
+ * @return true when `*out_code` holds a new value that must be written to the output.
+ */
+bool sweep_tick(sweep_t *sweep, uint16_t *out_code);
+
+#endif /* SWEEP_H */