RFID: Fix various EM-Marin typos (#635)

applications/lfrfid/helpers/decoder-emmarin.cpp

@@ -0,0 +1,72 @@
+#include "emmarin.h"
+#include "decoder-emmarin.h"
+#include <furi.h>
+#include <furi-hal.h>
+
+constexpr uint32_t clocks_in_us = 64;
+constexpr uint32_t short_time = 255 * clocks_in_us;
+constexpr uint32_t long_time = 510 * clocks_in_us;
+constexpr uint32_t jitter_time = 100 * clocks_in_us;
+
+constexpr uint32_t short_time_low = short_time - jitter_time;
+constexpr uint32_t short_time_high = short_time + jitter_time;
+constexpr uint32_t long_time_low = long_time - jitter_time;
+constexpr uint32_t long_time_high = long_time + jitter_time;
+
+void DecoderEMMarin::reset_state() {
+    ready = false;
+    readed_data = 0;
+    manchester_advance(
+        manchester_saved_state, ManchesterEventReset, &manchester_saved_state, nullptr);
+}
+
+bool DecoderEMMarin::read(uint8_t* data, uint8_t data_size) {
+    bool result = false;
+
+    if(ready) {
+        result = true;
+        em_marin.decode(
+            reinterpret_cast<const uint8_t*>(&readed_data), sizeof(uint64_t), data, data_size);
+        ready = false;
+    }
+
+    return result;
+}
+
+void DecoderEMMarin::process_front(bool polarity, uint32_t time) {
+    if(ready) return;
+    if(time < short_time_low) return;
+
+    ManchesterEvent event = ManchesterEventReset;
+
+    if(time > short_time_low && time < short_time_high) {
+        if(polarity) {
+            event = ManchesterEventShortHigh;
+        } else {
+            event = ManchesterEventShortLow;
+        }
+    } else if(time > long_time_low && time < long_time_high) {
+        if(polarity) {
+            event = ManchesterEventLongHigh;
+        } else {
+            event = ManchesterEventLongLow;
+        }
+    }
+
+    if(event != ManchesterEventReset) {
+        bool data;
+        bool data_ok =
+            manchester_advance(manchester_saved_state, event, &manchester_saved_state, &data);
+
+        if(data_ok) {
+            readed_data = (readed_data << 1) | data;
+
+            ready = em_marin.can_be_decoded(
+                reinterpret_cast<const uint8_t*>(&readed_data), sizeof(uint64_t));
+        }
+    }
+}
+
+DecoderEMMarin::DecoderEMMarin() {
+    reset_state();
+}