adiciona monitor cardíaco

heart_rate/main.c

@@ -0,0 +1,119 @@
+
+#include "wokwi-api.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+/* -------------------------------------------------- */
+/* States */
+
+typedef enum { STATE_NORMAL, STATE_RISING, STATE_FALLING } hr_state_t;
+
+typedef enum { STATE_SLOW = 0, STATE_FAST = 1 } hr_speed_t;
+
+/* -------------------------------------------------- */
+/* Chip state */
+
+typedef struct {
+  pin_t out_pin;
+  pin_t btn_pin;
+
+  float bpm;
+  int last_target;
+
+  hr_state_t state;
+  hr_speed_t speed;
+
+  int pulseValue;
+
+  timer_t update_timer;
+} chip_state_t;
+
+/* -------------------------------------------------- */
+/* Output mapping */
+
+static void update_output_voltage(chip_state_t *chip) {
+  float volts = (chip->bpm * 3.3f) / 675.0f;
+
+  if (volts < 0.0f)
+    volts = 0.0f;
+  if (volts > 3.3f)
+    volts = 3.3f;
+
+  pin_dac_write(chip->out_pin, volts);
+
+  printf("BPM: %.1f | Voltage: %.3fV\n", chip->bpm, volts);
+}
+
+/* -------------------------------------------------- */
+/* Main update loop */
+
+static void update_cb(void *user_data) {
+  chip_state_t *chip = user_data;
+
+  int target = attr_read(chip->pulseValue);
+
+  /* Read pull-down switch: LOW=SLOW, HIGH=FAST */
+  chip->speed = pin_read(chip->btn_pin) ? STATE_FAST : STATE_SLOW;
+
+  /* Detect target change and re-evaluate direction */
+  if (target != chip->last_target) {
+    if (chip->bpm < target) {
+      chip->state = STATE_RISING;
+    } else if (chip->bpm > target) {
+      chip->state = STATE_FALLING;
+    } else {
+      chip->state = STATE_NORMAL;
+    }
+    chip->last_target = target;
+  }
+
+  /* Step size */
+  float step = (chip->speed == STATE_FAST) ? 2.0f : 0.5f;
+
+  /* Rising */
+  if (chip->state == STATE_RISING) {
+    chip->bpm += step;
+    if (chip->bpm >= target) {
+      chip->bpm = target;
+      chip->state = STATE_NORMAL;
+    }
+  }
+
+  /* Falling */
+  if (chip->state == STATE_FALLING) {
+    chip->bpm -= step;
+    if (chip->bpm <= target) {
+      chip->bpm = target;
+      chip->state = STATE_NORMAL;
+    }
+  }
+
+  update_output_voltage(chip);
+}
+
+/* -------------------------------------------------- */
+/* Init */
+
+void chip_init(void) {
+  printf("Heart Rate chip init\n");
+
+  chip_state_t *chip = calloc(1, sizeof(chip_state_t));
+
+  /* Attribute: target BPM */
+  chip->pulseValue = attr_init("pulseValue", 100);
+
+  chip->bpm = 100.0f;
+  chip->last_target = 100;
+  chip->state = STATE_NORMAL;
+  chip->speed = STATE_SLOW;
+
+  chip->out_pin = pin_init("OUT", ANALOG);
+  chip->btn_pin = pin_init("BTN", INPUT); // pull-down switch
+
+  timer_config_t update_cfg = {.callback = update_cb, .user_data = chip};
+
+  chip->update_timer = timer_init(&update_cfg);
+
+  /* 50 ms update rate */
+  timer_start(chip->update_timer, 50000, true);
+}