diff --git a/esp32/main/CMakeLists.txt b/esp32/main/CMakeLists.txt
index 2e8421e..46b04b8 100644
--- a/esp32/main/CMakeLists.txt
+++ b/esp32/main/CMakeLists.txt
@@ -1,5 +1,5 @@
 idf_component_register(
-        SRCS "main.cpp" "protocol.cpp" "protocol_test.cpp" "wifi_manager.cpp" "system_init.cpp" "time_sync.cpp"
+        SRCS "main.cpp" "protocol.cpp" "wifi_manager.cpp" "system_init.cpp" "time_sync.cpp"
         INCLUDE_DIRS "."
         REQUIRES nvs_flash esp_wifi esp_netif freertos log cjson esp_timer
 )
diff --git a/esp32/main/main.cpp b/esp32/main/main.cpp
index 9902b36..1e3eef2 100644
--- a/esp32/main/main.cpp
+++ b/esp32/main/main.cpp
@@ -1,8 +1,9 @@
+#include "esp_log.h"
 #include "system_init.h"
-#include "protocol_test.h"
 #include "freertos/FreeRTOS.h"
 #include "freertos/projdefs.h"
 #include "freertos/task.h"
+#include "protocol.h"
 
 static const char* TAG = "iot_fish";
 
@@ -10,9 +11,14 @@ extern "C" void app_main(void)
 {
     system_init();
 
-    for (int i=0; i<10; i++)
+    for (int i=0; i<5; i++)
     {
-        protocol_run_tests();
+        char buf[512];
+        int len = build_telemetry_single(buf, sizeof(buf), "123", "dev1", 123456, "temperature", 22.5, "C", nullptr, 0);
+
+        if (len > 0) {
+            ESP_LOGI("protocol", "%s\n", buf);
+        }
         vTaskDelay(pdMS_TO_TICKS(1000));
     }
 
diff --git a/esp32/main/protocol.cpp b/esp32/main/protocol.cpp
index 61ebe0d..683da8b 100644
--- a/esp32/main/protocol.cpp
+++ b/esp32/main/protocol.cpp
@@ -1,52 +1,123 @@
 #include "protocol.h"
-#include "cJSON.h"
+#include <stdio.h>
+#include <stdarg.h>
 
-cJSON* protocol_message_to_json(const ProtocolMessage* msg) {
-    cJSON* root = cJSON_CreateObject();
+#define PROTOCOL_VERSION 1
 
-    cJSON_AddNumberToObject(root, "v", msg->v);
-    cJSON_AddStringToObject(root, "id", msg->id.c_str());
-    cJSON_AddStringToObject(root, "type", msg->type.c_str());
-    cJSON_AddNumberToObject(root, "ts", msg->ts);
-    cJSON_AddStringToObject(root, "deviceId", msg->deviceId.c_str());
+static inline int append(char* buf, size_t size, int pos, const char* fmt, ...) {
+    if ((size_t)pos >= size) return -1;
 
-    cJSON* payload_obj = nullptr;
-    if (msg->payload) {
-        payload_obj = cJSON_Duplicate(msg->payload, 1); // deep copy
-    } else {
-        payload_obj = cJSON_CreateObject();
+    va_list args;
+    va_start(args, fmt);
+    int written = vsnprintf(buf + pos, size - pos, fmt, args);
+    va_end(args);
+
+    if (written < 0 || (size_t)(pos + written) >= size) {
+        return -1;
     }
-    cJSON_AddItemToObject(root, "payload", payload_obj);
 
-    return root;
+    return pos + written;
 }
 
-ProtocolMessage protocol_message_from_json(const cJSON* root) {
-    ProtocolMessage msg;
+// --- TELEMETRY (single measurement) ---
+int build_telemetry_single(
+    char* buf,
+    size_t buf_size,
+    const char* id,
+    const char* device_id,
+    int64_t ts_ms,
+    const char* metric,
+    double value,
+    const char* unit,
+    const char* source,
+    int64_t m_ts_ms
+) {
+    int pos = 0;
 
-    const cJSON* item = nullptr;
+    // header
+    pos = append(buf, buf_size, pos,
+        "{\"v\":%d,\"id\":\"%s\",\"type\":\"telemetry\",\"ts\":%lld,"
+        "\"deviceId\":\"%s\",\"payload\":{\"measurements\":[",
+        PROTOCOL_VERSION,
+        id,
+        (long long)ts_ms,
+        device_id
+    );
+    if (pos < 0) return -1;
 
-    item = cJSON_GetObjectItem(root, "v");
-    if (item && cJSON_IsNumber(item)) msg.v = item->valueint;
+    // measurement start
+    pos = append(buf, buf_size, pos,
+        "{\"metric\":\"%s\",\"value\":%.3f",
+        metric,
+        value
+    );
+    if (pos < 0) return -1;
 
-    item = cJSON_GetObjectItem(root, "id");
-    if (item && cJSON_IsString(item)) msg.id = item->valuestring;
-
-    item = cJSON_GetObjectItem(root, "type");
-    if (item && cJSON_IsString(item)) msg.type = item->valuestring;
-
-    item = cJSON_GetObjectItem(root, "ts");
-    if (item && cJSON_IsNumber(item)) msg.ts = item->valuedouble; // uint64_t
-
-    item = cJSON_GetObjectItem(root, "deviceId");
-    if (item && cJSON_IsString(item)) msg.deviceId = item->valuestring;
-
-    item = cJSON_GetObjectItem(root, "payload");
-    if (item && cJSON_IsObject(item)) {
-        msg.payload = cJSON_Duplicate(item, 1); // deep copy
-    } else {
-        msg.payload = cJSON_CreateObject();
+    // optional
+    if (unit) {
+        pos = append(buf, buf_size, pos, ",\"unit\":\"%s\"", unit);
+        if (pos < 0) return -1;
     }
 
-    return msg;
+    if (source) {
+        pos = append(buf, buf_size, pos, ",\"source\":\"%s\"", source);
+        if (pos < 0) return -1;
+    }
+
+    if (m_ts_ms > 0) {
+        pos = append(buf, buf_size, pos, ",\"ts\":%lld", (long long)m_ts_ms);
+        if (pos < 0) return -1;
+    }
+
+    // close measurement + payload
+    pos = append(buf, buf_size, pos, "}]}}");
+    if (pos < 0) return -1;
+
+    return pos;
+}
+
+// --- EVENT ---
+int build_event(
+    char* buf,
+    size_t buf_size,
+    const char* id,
+    const char* device_id,
+    int64_t ts_ms,
+    const char* name,
+    const char* severity,
+    const char* message
+) {
+    int pos = 0;
+
+    // header
+    pos = append(buf, buf_size, pos,
+        "{\"v\":%d,\"id\":\"%s\",\"type\":\"event\",\"ts\":%lld,"
+        "\"deviceId\":\"%s\",\"payload\":{",
+        PROTOCOL_VERSION,
+        id,
+        (long long)ts_ms,
+        device_id
+    );
+    if (pos < 0) return -1;
+
+    // required
+    pos = append(buf, buf_size, pos, "\"name\":\"%s\"", name);
+    if (pos < 0) return -1;
+
+    // optional
+    if (severity) {
+        pos = append(buf, buf_size, pos, ",\"severity\":\"%s\"", severity);
+        if (pos < 0) return -1;
+    }
+
+    if (message) {
+        pos = append(buf, buf_size, pos, ",\"message\":\"%s\"", message);
+        if (pos < 0) return -1;
+    }
+
+    // close
+    pos = append(buf, buf_size, pos, "}}");
+    if (pos < 0) return -1;
+
+    return pos;
 }
\ No newline at end of file
diff --git a/esp32/main/protocol.h b/esp32/main/protocol.h
index 4d91d40..59a4fc7 100644
--- a/esp32/main/protocol.h
+++ b/esp32/main/protocol.h
@@ -1,18 +1,36 @@
 #pragma once
-#include "cJSON.h"
-#include <string>
 
-struct ProtocolMessage {
-    int v;
-    std::string id;
-    std::string type;
-    uint64_t ts;
-    std::string deviceId; // C++ строка
-    cJSON* payload;
-};
+#include <stdint.h>
+#include <stddef.h>
 
-// Создание JSON из структуры
-cJSON* protocol_message_to_json(const ProtocolMessage *msg);
+#ifdef __cplusplus
+extern "C" {
+#endif
 
-// Разбор JSON в структуру
-int protocol_json_to_message(const char *json_str, ProtocolMessage *msg);
\ No newline at end of file
+int build_telemetry_single(
+    char* buf,
+    size_t buf_size,
+    const char* id,
+    const char* device_id,
+    int64_t ts_ms,
+    const char* metric,
+    double value,
+    const char* unit,     // optional (NULL)
+    const char* source,   // optional (NULL)
+    int64_t m_ts_ms       // optional (0 = нет)
+);
+
+int build_event(
+    char* buf,
+    size_t buf_size,
+    const char* id,
+    const char* device_id,
+    int64_t ts_ms,
+    const char* name,
+    const char* severity, // optional
+    const char* message   // optional
+);
+
+#ifdef __cplusplus
+}
+#endif
\ No newline at end of file
diff --git a/esp32/main/protocol_test.cpp b/esp32/main/protocol_test.cpp
deleted file mode 100644
index cba1918..0000000
--- a/esp32/main/protocol_test.cpp
+++ /dev/null
@@ -1,32 +0,0 @@
-#include "protocol_test.h"
-
-#include "protocol.h"
-#include "cJSON.h"
-#include "esp_log.h"
-#include "esp_timer.h"
-
-static const char* TAG = "protocol_test";
-
-void protocol_run_tests()
-{
-    ESP_LOGI(TAG, "Running protocol test...");
-
-    ProtocolMessage msg;
-    msg.v = 1;
-    msg.id = "msg-001";
-    msg.type = "command";
-    msg.deviceId = "esp32-01";
-    msg.ts = esp_timer_get_time();
-
-    msg.payload = cJSON_CreateObject();
-    cJSON_AddStringToObject(msg.payload, "command", "ping");
-
-    cJSON* json = protocol_message_to_json(&msg);
-    char* json_str = cJSON_Print(json);
-
-    ESP_LOGI(TAG, "ProtocolMessage JSON:\n%s", json_str);
-
-    cJSON_Delete(json);
-    free(json_str);
-    cJSON_Delete(msg.payload);
-}
diff --git a/esp32/main/protocol_test.h b/esp32/main/protocol_test.h
deleted file mode 100644
index 6101e43..0000000
--- a/esp32/main/protocol_test.h
+++ /dev/null
@@ -1,3 +0,0 @@
-#pragma once
-
-void protocol_run_tests();
\ No newline at end of file
diff --git a/esp32/sdkconfig.defaults b/esp32/sdkconfig.defaults
new file mode 100644
index 0000000..a46a58c
--- /dev/null
+++ b/esp32/sdkconfig.defaults
@@ -0,0 +1,6 @@
+# This file was generated using idf.py save-defconfig. It can be edited manually.
+# Espressif IoT Development Framework (ESP-IDF) 6.0.0 Project Minimal Configuration
+#
+CONFIG_WIFI_SSID="IoT_ext"
+CONFIG_WIFI_PASS="s1SgU2W3d5UEQi"
+CONFIG_SERVER_HOST="192.168.17.90"
diff --git a/esp32/sdkconfig.defaults.bak b/esp32/sdkconfig.defaults.bak
new file mode 100644
index 0000000..a46a58c
--- /dev/null
+++ b/esp32/sdkconfig.defaults.bak
@@ -0,0 +1,6 @@
+# This file was generated using idf.py save-defconfig. It can be edited manually.
+# Espressif IoT Development Framework (ESP-IDF) 6.0.0 Project Minimal Configuration
+#
+CONFIG_WIFI_SSID="IoT_ext"
+CONFIG_WIFI_PASS="s1SgU2W3d5UEQi"
+CONFIG_SERVER_HOST="192.168.17.90"
diff --git a/esp32/sdkconfig.defaults.esp32 b/esp32/sdkconfig.defaults.esp32
new file mode 100644
index 0000000..b003eda
--- /dev/null
+++ b/esp32/sdkconfig.defaults.esp32
@@ -0,0 +1 @@
+CONFIG_ESP_CONSOLE_UART=y
\ No newline at end of file
diff --git a/esp32/sdkconfig.defaults.esp32s2 b/esp32/sdkconfig.defaults.esp32s2
new file mode 100644
index 0000000..7862a9c
--- /dev/null
+++ b/esp32/sdkconfig.defaults.esp32s2
@@ -0,0 +1,12 @@
+    # This file was generated using idf.py save-defconfig. It can be edited manually.
+    # Espressif IoT Development Framework (ESP-IDF) 6.0.0 Project Minimal Configuration
+    #
+    # default:
+CONFIG_IDF_TARGET="esp32s2"
+CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y
+CONFIG_ESP_CONSOLE_USB_CDC=y
+CONFIG_ESP_CONSOLE_USB_CDC_RX_BUF_SIZE=128
+CONFIG_ESP_CONSOLE_USB_CDC_SUPPORT_ETS_PRINTF=y
+CONFIG_WIFI_SSID="IoT_ext"
+CONFIG_WIFI_PASS="s1SgU2W3d5UEQi"
+CONFIG_SERVER_HOST="192.168.17.90"