diff --git a/armsrc/Standalone/hf_colin.c b/armsrc/Standalone/hf_colin.c
index dd6de79e3..9776d4b46 100644
--- a/armsrc/Standalone/hf_colin.c
+++ b/armsrc/Standalone/hf_colin.c
@@ -105,8 +105,8 @@ void ReadLastTagFromFlash() {
     }
     Flash_CheckBusy(BUSY_TIMEOUT);
 
-    uint32_t end_time;
-    uint32_t start_time = end_time = GetTickCount();
+    uint32_t start_time = GetTickCount();
+    uint32_t delta_time = 0;
 
     for (size_t i = 0; i < len; i += size) {
         len = MIN((len - i), size);
@@ -121,7 +121,7 @@ void ReadLastTagFromFlash() {
             return;
         }
     }
-    end_time = GetTickCount();
+    delta_time = GetTickCountDelta(start_time);
     DbprintfEx(FLAG_NEWLINE, "[OK] Last tag recovered from FLASHMEM set to emulator");
     cjSetCursLeft();
     DbprintfEx(FLAG_NEWLINE, "%s[IN]%s %s%dms%s for TAG_FLASH_READ", _GREEN_, _WHITE_, _YELLOW_, end_time - start_time, _WHITE_);
@@ -155,8 +155,8 @@ void WriteTagToFlash(uint8_t index, size_t size) {
     Flash_WriteEnable();
     Flash_Erase4k(0, 0);
 
-    uint32_t end_time;
-    uint32_t start_time = end_time = GetTickCount();
+    uint32_t start_time = GetTickCount();
+    uint32_t delta_time = 0;
 
     while (bytes_remaining > 0) {
         Flash_CheckBusy(BUSY_TIMEOUT);
@@ -184,7 +184,7 @@ void WriteTagToFlash(uint8_t index, size_t size) {
         LED_C_INV();
         LED_D_INV();
     }
-    end_time = GetTickCount();
+    delta_time = GetTickCountDelta(start_time);
 
     DbprintfEx(FLAG_NEWLINE, "[OK] TAG WRITTEN TO FLASH ! [0-to offset %u]", bytes_sent);
     cjSetCursLeft();
@@ -393,8 +393,8 @@ failtag:
     cjSetCursRight();
     DbprintfEx(FLAG_NEWLINE, "--------+--------------------+-------");
 
-    uint32_t end_time;
-    uint32_t start_time = end_time = GetTickCount();
+    uint32_t start_time = GetTickCount();
+    uint32_t delta_time = 0;
 
     //---------------------------------------------------------------------------
     // WE SHOULD FIND A WAY TO GET UID TO AVOID THIS "TESTRUN"
@@ -736,7 +736,7 @@ failtag:
         }
     }
 
-    end_time = GetTickCount();
+    delta_time = GetTickCountDelta(start_time);
     cjSetCursLeft();
 
     DbprintfEx(FLAG_NEWLINE, "%s>>%s Time for VIGIK break :%s%dms%s", _GREEN_, _WHITE_, _YELLOW_, end_time - start_time, _WHITE_);
diff --git a/armsrc/appmain.c b/armsrc/appmain.c
index 78c9a8571..cdd63efe3 100644
--- a/armsrc/appmain.c
+++ b/armsrc/appmain.c
@@ -382,23 +382,22 @@ void printConnSpeed(void) {
 
 #define CONN_SPEED_TEST_MIN_TIME 500 // in milliseconds
     uint8_t *test_data = BigBuf_get_addr();
-    uint32_t end_time;
-
-    uint32_t start_time = end_time = GetTickCount();
+    uint32_t start_time = GetTickCount();
+    uint32_t delta_time = 0;
     uint32_t bytes_transferred = 0;
 
     LED_B_ON();
 
-    while (end_time < start_time + CONN_SPEED_TEST_MIN_TIME) {
+    while (delta_time < CONN_SPEED_TEST_MIN_TIME) {
         reply_ng(CMD_DOWNLOADED_BIGBUF, PM3_SUCCESS, test_data, PM3_CMD_DATA_SIZE);
-        end_time = GetTickCount();
         bytes_transferred += PM3_CMD_DATA_SIZE;
+        delta_time = GetTickCountDelta(start_time);
     }
     LED_B_OFF();
 
-    Dbprintf("  Time elapsed............%dms", end_time - start_time);
+    Dbprintf("  Time elapsed............%dms", delta_time);
     Dbprintf("  Bytes transferred.......%d", bytes_transferred);
-    Dbprintf("  Transfer Speed PM3 -> Client = " _YELLOW_("%d") " bytes/s", 1000 * bytes_transferred / (end_time - start_time));
+    Dbprintf("  Transfer Speed PM3 -> Client = " _YELLOW_("%d") " bytes/s", 1000 * bytes_transferred / delta_time);
 }
 
 /**
diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index 15d17d8b8..8be3f3640 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -1623,7 +1623,7 @@ void CodeIso14443aAsReaderPar(const uint8_t *cmd, uint16_t len, const uint8_t *p
 int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *par) {
     *len = 0;
 
-    uint32_t timer = 0, vtime;
+    uint32_t timer = 0;
     int analogCnt = 0;
     int analogAVG = 0;
 
@@ -1662,11 +1662,17 @@ int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *par) {
             AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
             if (analogCnt >= 32) {
                 if ((MAX_ADC_HF_VOLTAGE_RDV40 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
-                    vtime = GetTickCount();
-                    if (!timer) timer = vtime;
-                    // 50ms no field --> card to idle state
-                    if (vtime - timer > 50) return 2;
-                } else if (timer) timer = 0;
+                    if (timer == 0) {
+                        timer = GetTickCount();
+                    } else {
+                        // 50ms no field --> card to idle state
+                        if (GetTickCountDelta(timer) > 50) {
+                            return 2;
+                        }
+                    }
+                } else {
+                    timer = 0;
+                }
                 analogCnt = 0;
                 analogAVG = 0;
             }
@@ -2041,7 +2047,7 @@ static int GetATQA(uint8_t *resp, uint8_t *resp_par) {
         ReaderTransmitBitsPar(wupa, 7, NULL, NULL);
         // Receive the ATQA
         len = ReaderReceive(resp, resp_par);
-    } while (len == 0 && GetTickCount() <= start_time + WUPA_RETRY_TIMEOUT);
+    } while (len == 0 && GetTickCountDelta(start_time) <= WUPA_RETRY_TIMEOUT);
 
     iso14a_set_timeout(save_iso14a_timeout);
     return len;