[FL-3880] Fix cumulative error in infrared signals (#3823)

* Correct for pulse duration cumulative discrepancy
* Add infrared test application
* Build infrared_test_app for f7 only

Co-authored-by: あく <alleteam@gmail.com>

applications/debug/infrared_test/application.fam

@@ -0,0 +1,8 @@
+App(
+    appid="infrared_test",
+    name="Infrared Test",
+    apptype=FlipperAppType.DEBUG,
+    entry_point="infrared_test_app",
+    fap_category="Debug",
+    targets=["f7"],
+)

applications/debug/infrared_test/infrared_test.c

@@ -0,0 +1,61 @@
+#include <furi.h>
+#include <furi_hal_infrared.h>
+
+#define TAG "InfraredTest"
+
+#define CARRIER_FREQ_HZ (38000UL)
+#define CARRIER_DUTY    (0.33f)
+
+#define BURST_DURATION_US (600UL)
+#define BURST_COUNT       (50UL)
+
+typedef struct {
+    bool level;
+    uint32_t count;
+} InfraredTestApp;
+
+static FuriHalInfraredTxGetDataState
+    infrared_test_app_tx_data_callback(void* context, uint32_t* duration, bool* level) {
+    furi_assert(context);
+    furi_assert(duration);
+    furi_assert(level);
+
+    InfraredTestApp* app = context;
+
+    *duration = BURST_DURATION_US;
+    *level = app->level;
+
+    app->level = !app->level;
+    app->count += 1;
+
+    if(app->count < BURST_COUNT * 2) {
+        return FuriHalInfraredTxGetDataStateOk;
+    } else {
+        return FuriHalInfraredTxGetDataStateLastDone;
+    }
+}
+
+int32_t infrared_test_app(void* arg) {
+    UNUSED(arg);
+
+    InfraredTestApp app = {
+        .level = true,
+    };
+
+    FURI_LOG_I(TAG, "Starting test signal on PA7");
+
+    furi_hal_infrared_set_tx_output(FuriHalInfraredTxPinExtPA7);
+    furi_hal_infrared_async_tx_set_data_isr_callback(infrared_test_app_tx_data_callback, &app);
+    furi_hal_infrared_async_tx_start(CARRIER_FREQ_HZ, CARRIER_DUTY);
+    furi_hal_infrared_async_tx_wait_termination();
+    furi_hal_infrared_set_tx_output(FuriHalInfraredTxPinInternal);
+
+    FURI_LOG_I(TAG, "Test signal end");
+    FURI_LOG_I(
+        TAG,
+        "The measured signal should be %luus +-%.1fus",
+        (app.count - 1) * BURST_DURATION_US,
+        (double)1000000.0 / CARRIER_FREQ_HZ);
+
+    return 0;
+}