diff --git a/CanUds.c b/CanUds.c
index 83bcba4..ac1ebb8 100644
--- a/CanUds.c
+++ b/CanUds.c
@@ -235,8 +235,6 @@ void setResponseErrorPending(tCanUds *env, eUdsServices service, eUdsResponseErr
 }
 
 
-
-
 static void setDefaultSecurityAccess(tCanUds *env) {
     env->SA.requestSequenceRequestSeed = false;
     env->SA.stateSecurityAccess = false;
@@ -1331,12 +1329,14 @@ static uint16_t RequestDownload_34(tCanUds *env) {
     requestDownload_Response->ServiceId = UDS_RequestDownload | 0b1000000;
     requestDownload_Response->lengthFormatIdentifier = 0x20; // 2 байта - длина поля maxNumberOfBlockLength
 
-    uint8_t countBlock = 1;
+    uint8_t countBlock = 8;
     requestDownload_Response->maxNumberOfBlockLength = countBlock * 128 + 2;
 
     env->AdrFlash = 0x1100000;
     env->SizeWriteFlash = 0;
 
+    env->stateDownload = UDS_RequestDownload;
+
 //    vCanSerialPortSetMaskCount(env->CanIO->env, 2);
 
     return 4;
@@ -1367,7 +1367,20 @@ static uint16_t TransferData_36(tCanUds *env) {
         return setResponseError(env, UDS_RoutineControl, UDS_error_securityAccessDenied);
     }
 
-//    setResponseErrorPending(env, UDS_RoutineControl, UDS_error_requestCorrectlyReceived_ResponsePending);
+    if (env->stateDownload == UDS_RequestDownload) {
+        env->stateDownload = UDS_TransferData;
+    } else {
+        if (env->stateDownload != UDS_TransferData) {
+            return setResponseError(env, UDS_RoutineControl, UDS_error_requestSequenceError);
+        }
+    }
+
+    if (env->SizeWriteFlash >= DownloadFirmwareSize) {
+        return setResponseError(env, UDS_RoutineControl, UDS_error_requestSequenceError);
+    }
+
+
+    //    setResponseErrorPending(env, UDS_RoutineControl, UDS_error_requestCorrectlyReceived_ResponsePending);
 
     if (osMutexAcquire(env->access, 1000) == osOK) {
         env->currentSessionTesterPresentTimeout = SystemGetMs() + timeout_session_S3_Server;
@@ -1383,7 +1396,7 @@ static uint16_t TransferData_36(tCanUds *env) {
     env->AdrFlash += env->data->len - 2;
     env->SizeWriteFlash += env->data->len - 2;
 
-//    LoggerFormatInfo(LOGGER, LOG_SIGN, "Size Write Flash = %d", env->SizeWriteFlash)
+    LoggerFormatInfo(LOGGER, LOG_SIGN, "Download: %d of %d kb", env->SizeWriteFlash / 1024 , DownloadFirmwareSize / 1024)
 
     tTransferData_Response *transferData_Response = (tTransferData_Response *) env->dataResponse;
     transferData_Response->ServiceId = UDS_TransferData | 0b1000000;
@@ -1406,6 +1419,11 @@ static uint16_t RequestTransferExit_37(tCanUds *env) {
         return setResponseError(env, UDS_RoutineControl, UDS_error_conditionsNotCorrect);
     }
 
+    if ((env->stateDownload != UDS_TransferData) || (env->SizeWriteFlash < DownloadFirmwareSize)) {
+        return setResponseError(env, UDS_RoutineControl, UDS_error_requestSequenceError);
+    } else {
+        env->stateDownload = UDS_RequestTransferExit;
+    }
 
     tRequestTransferExit_Request *com = (tRequestTransferExit_Request *) env->data->data;
 
diff --git a/CanUds.h b/CanUds.h
index ab7cb42..1131da6 100644
--- a/CanUds.h
+++ b/CanUds.h
@@ -15,6 +15,8 @@
 
 //#define CAN_US_QUEUE_SIZE 1
 
+#define DownloadFirmwareSize (512 * 1024)
+
 #define MAX_ATTEMPTS_DEFAULT     3
 #define BLOCK_TIME_DEFAULT       60000
 
@@ -189,6 +191,8 @@ typedef struct {
     uint32_t SizeWriteFlash;
     uint8_t blockSequenceCounter;
 
+    eUdsServices stateDownload;
+
     tStaticThreadBlock(384) T_can_Uds;
 } tCanUds;