diff --git a/F0:F030,F042,F072/TSYS_controller/can_process.c b/F0:F030,F042,F072/TSYS_controller/can_process.c
index b850a73..4437138 100644
--- a/F0:F030,F042,F072/TSYS_controller/can_process.c
+++ b/F0:F030,F042,F072/TSYS_controller/can_process.c
@@ -113,6 +113,8 @@ void can_messages_proc(){
                 SEND("DUMMY");
                 bufputchar('0' + (data[1]==CMD_DUMMY0 ? 0 : 1));
                 newline();
+                b[0] = CMD_PING;
+                can_send_data(b, 1); // return to slave: pong
             break;
             case CMD_PING: // pong
                 can_send_data(b, 1);
@@ -174,6 +176,9 @@ void can_messages_proc(){
                 *((uint32_t*)&b[2]) = Tms;
                 can_send_data(b, 6);
             break;
+            case CMD_RESET_MCU:
+                NVIC_SystemReset();
+            break;
         }
     }else if(data[0] == DATA_MARK){ // process received data
         char Ns = '0' + data[1];
diff --git a/F0:F030,F042,F072/TSYS_controller/can_process.h b/F0:F030,F042,F072/TSYS_controller/can_process.h
index d78fc4b..a57f8a4 100644
--- a/F0:F030,F042,F072/TSYS_controller/can_process.h
+++ b/F0:F030,F042,F072/TSYS_controller/can_process.h
@@ -50,6 +50,7 @@ typedef enum{
     CMD_REINIT_SENSORS,     // (re)init sensors
     CMD_GETBUILDNO,         // request for firmware build number
     CMD_SYSTIME,            // get system time
+    CMD_RESET_MCU,          // reset MCU
     // dummy commands for test purposes
     CMD_DUMMY0 = 0xDA,
     CMD_DUMMY1 = 0xAD
diff --git a/F0:F030,F042,F072/TSYS_controller/i2c.h b/F0:F030,F042,F072/TSYS_controller/i2c.h
index 7c6ab65..97b99af 100644
--- a/F0:F030,F042,F072/TSYS_controller/i2c.h
+++ b/F0:F030,F042,F072/TSYS_controller/i2c.h
@@ -35,7 +35,7 @@
 #define TSYS01_START_CONV       (0x48)
 #define TSYS01_PROM_ADDR0       (0xA0)
 // conversion time (with reserve)
-#define CONV_TIME               (15)
+#define CONV_TIME               (25)
 
 uint8_t read_i2c(uint8_t addr, uint32_t *data, uint8_t nbytes);
 uint8_t write_i2c(uint8_t addr, uint8_t data);
diff --git a/F0:F030,F042,F072/TSYS_controller/main.c b/F0:F030,F042,F072/TSYS_controller/main.c
index 869c306..21841e4 100644
--- a/F0:F030,F042,F072/TSYS_controller/main.c
+++ b/F0:F030,F042,F072/TSYS_controller/main.c
@@ -44,6 +44,7 @@ void sys_tick_handler(void){
     ++Tms;
 }
 
+#if 0
 static void iwdg_setup(){
     /* Enable the peripheral clock RTC */
     /* (1) Enable the LSI (40kHz) */
@@ -64,6 +65,7 @@ static void iwdg_setup(){
     while(IWDG->SR); /* (5) */
     IWDG->KR = IWDG_REFRESH; /* (6) */
 }
+#endif
 
 int main(void){
     uint32_t lastT = 0, lastS = 0, lastB = 0;
@@ -81,7 +83,7 @@ int main(void){
     RCC->CSR |= RCC_CSR_RMVF; // remove reset flags
     USB_setup();
     sensors_init();
-    iwdg_setup();
+    //iwdg_setup();
 
     while (1){
         IWDG->KR = IWDG_REFRESH; // refresh watchdog
@@ -130,7 +132,7 @@ int main(void){
 #endif
             cmd_parser(txt, 0);
         }
-        if(lastB - Tms > 99){ // run `sendbuf` each 100ms
+        if(lastB - Tms > 249){ // run `sendbuf` each 250ms
             sendbuf();
             lastB = Tms;
         }
diff --git a/F0:F030,F042,F072/TSYS_controller/proto.c b/F0:F030,F042,F072/TSYS_controller/proto.c
index cd7f675..c66e2df 100644
--- a/F0:F030,F042,F072/TSYS_controller/proto.c
+++ b/F0:F030,F042,F072/TSYS_controller/proto.c
@@ -58,7 +58,7 @@ void sendbuf(){
     if(blen == 0) return;
     *bptr = 0;
     if(USBcmd) USB_send(buff);
-    else while(LINE_BUSY == usart_send(buff, blen)){IWDG->KR = IWDG_REFRESH;}
+    else for(int i = 0; (i < 9999) && (LINE_BUSY == usart_send(buff, blen)); ++i){IWDG->KR = IWDG_REFRESH;}
     bptr = buff;
     blen = 0;
 }
@@ -69,7 +69,7 @@ void addtobuf(const char *txt){
     if(l > UARTBUFSZ){
         sendbuf(); // send prevoius data in buffer
         if(USBcmd) USB_send(txt);
-        else while(LINE_BUSY == usart_send_blocking(txt, l)){IWDG->KR = IWDG_REFRESH;}
+        else for(int i = 0; (i < 9999) && (LINE_BUSY == usart_send_blocking(txt, l)); ++i){IWDG->KR = IWDG_REFRESH;}
     }else{
         if(blen+l > UARTBUFSZ){
             sendbuf();
@@ -222,6 +222,10 @@ void cmd_parser(char *txt, uint8_t isUSB){
         }
     }
     switch(_1st){
+        case '#':
+            if(ID == BCAST_ID) NVIC_SystemReset();
+            CANsend(ID, CMD_RESET_MCU, _1st);
+        break;
         case '@':
             debugmode = !debugmode;
             SEND("DEBUG mode ");
@@ -336,7 +340,7 @@ void cmd_parser(char *txt, uint8_t isUSB){
             CANsend(ID, CMD_START_MEASUREMENT, _1st);
         break;
         case 't':
-            if(!sensors_scan_mode) sensors_start();
+            sensors_start();
         break;
         case 'u':
             SEND("Unique ID CAN mode\n");
@@ -380,8 +384,9 @@ void cmd_parser(char *txt, uint8_t isUSB){
             SEND("https://github.com/eddyem/tsys01/tree/master/STM32/TSYS_controller build#" BUILD_NUMBER " @ " BUILD_DATE "\n");
             SEND(
             "ALL little letters - without CAN messaging\n"
+            "# - reset MCU (self or with given ID like '1#')\n"
             "0..7 - send command to given controller (0 - this) instead of broadcast\n"
-            "@ - set/reset debug mode\n"
+            "@ - set/clear debug mode\n"
             "a - get raw ADC values\n"
             "B - send broadcast CAN dummy message\n"
             "b - get/set CAN bus baudrate\n"
diff --git a/F0:F030,F042,F072/TSYS_controller/sensors_manage.c b/F0:F030,F042,F072/TSYS_controller/sensors_manage.c
index 20b67b0..a53766a 100644
--- a/F0:F030,F042,F072/TSYS_controller/sensors_manage.c
+++ b/F0:F030,F042,F072/TSYS_controller/sensors_manage.c
@@ -116,11 +116,13 @@ void sensors_off(){
 static int sensors_on(){
     mesg("Turn on sensors");
     curr_mul_addr = 0;
+    sensors_scan_mode = 0;
     MUL_OFF();
     if(SENSORS_OVERCURNT()){
         mesg("OVERCURRENT!");
         SENSORS_OFF();
         Sstate = (++overcurnt_ctr > 32) ? SENS_OVERCURNT_OFF : SENS_OVERCURNT;
+        if(Sstate == SENS_OVERCURNT_OFF) mesg("sensors_on() ---> OFF by overcurrent");
         return FALSE;
     }else{
         mesg("Powered on");
@@ -143,7 +145,7 @@ void sensors_init(){
  * do nothing if measurement processing
  */
 void sensors_start(){
-    if(sensors_scan_mode) return;
+    //if(sensors_scan_mode) return;
     switch(Sstate){
         case SENS_SLEEPING:
             Sstate = SENS_START_MSRMNT;
@@ -263,11 +265,13 @@ static uint8_t gettempproc(){
                 if(BAD_TEMPERATURE != (Temperatures[curr_mul_addr][i] = calc_t(t, i))){
                     err = 0;
                     ++Ntemp_measured;
-                }
+                    mesg("  got one T");
+                }else mesg("  bad T");
             }
         }
         if(err){
             write_i2c(Taddr[i], TSYS01_RESET);
+            mesg("  i2c err");
         }
     }
     return TRUE;
@@ -357,9 +361,11 @@ void showtemperature(){
 void sensors_process(){
     static int8_t NsentOverCAN = -1; // number of T (N*10+p) sent over CAN bus; -1 - nothing to send
     if(SENSORS_OVERCURNT()){
+        mesg("sensors_process(): overcurrent!");
         MUL_OFF();
         SENSORS_OFF();
         Sstate = (++overcurnt_ctr > 32) ? SENS_OVERCURNT_OFF : SENS_OVERCURNT;
+        if(Sstate == SENS_OVERCURNT_OFF) mesg("sensors_process(): ---> OFF by overcurrent");
         return;
     }
     switch(Sstate){
@@ -368,18 +374,19 @@ void sensors_process(){
             i2c_setup(CURRENT_SPEED);
             Sstate = SENS_RESETING;
             lastSensT = Tms;
-            NsentOverCAN = -1;
+            //NsentOverCAN = -1;
         break;
         case SENS_RESETING: // reset & discovery procedure
-            if(NsentOverCAN == -1){
+            /*if(NsentOverCAN == -1){
                 mesg("SENS_RESETING");
                 NsentOverCAN = 0;
-            }
+            }*/
             if(Tms - lastSensT > POWERUP_TIME){
                 if(sensors_scan(resetproc)){
                     count_sensors(); // get total amount of sensors
                     if(Nsens_present){
                         Sstate = SENS_GET_COEFFS;
+                        mesg("SENS_RESETING -> SENS_GET_COEFFS");
                     }else{ // no sensors found
                         mesg("No sensors found -> off");
                         sensors_off();
@@ -388,39 +395,39 @@ void sensors_process(){
             }
         break;
         case SENS_GET_COEFFS: // get coefficients
-            mesg("SENS_GET_COEFFS");
             if(sensors_scan(getcoefsproc)){
                 Sstate = SENS_SLEEPING; // sleep after got coefficients
+                mesg("SENS_GET_COEFFS -> SENS_SLEEPING");
             }
         break;
         case SENS_START_MSRMNT: // send all sensors command to start measurements
-            mesg("SENS_START_MSRMNT");
             if(sensors_scan(msrtempproc)){
                 lastSensT = Tms;
                 Sstate = SENS_WAITING;
                 Ntemp_measured = 0; // reset value of good measurements
+                mesg("SENS_START_MSRMNT -> SENS_WAITING");
             }
         break;
         case SENS_WAITING: // wait for end of conversion
-            mesg("SENS_WAITING");
             if(Tms - lastSensT > CONV_TIME){
-                NsentOverCAN = -1;
+                //NsentOverCAN = -1;
+                mesg("SENS_WAITING -> SENS_GATHERING");
                 Sstate = SENS_GATHERING;
             }
         break;
         case SENS_GATHERING: // scan all sensors, get thermal data & calculate temperature
-            if(NsentOverCAN < 0){
-                mesg("SENS_SLEEPING");
+            /*if(NsentOverCAN < 0){
+                mesg("SENS_GATHERING");
                 NsentOverCAN = 0;
-            }
+            }*/
             if(sensors_scan(gettempproc)){
                 lastSensT = Tms;
                 NsentOverCAN = 0;
                 Sstate = SENS_SENDING_DATA;
+                mesg("SENS_GATHERING -> SENS_SENDING_DATA");
             }
         break;
         case SENS_SENDING_DATA:
-            mesg("SENS_SENDING_DATA");
             if(Nsens_present == 0){
                 mesg("No sensors found -> off");
                 sensors_off();
@@ -430,6 +437,7 @@ void sensors_process(){
             NsentOverCAN = send_temperatures(NsentOverCAN); // call sending T process
             if(NsentOverCAN < 0){ // all data sent -> sleep
                 Sstate = SENS_SLEEPING;
+                mesg("SENS_SENDING_DATA -> SENS_SLEEPING");
                 /*
                 if(Nsens_present != Ntemp_measured){ // restart sensors only after measurements sent
                         mesg("restart");
@@ -439,13 +447,14 @@ void sensors_process(){
             }
         break;
         case SENS_SLEEPING: // wait for `SLEEP_TIME` till next measurements in scan mode
-            if(NsentOverCAN < 0){
+            /*if(NsentOverCAN < 0){
                 mesg("SENS_SLEEPING");
                 NsentOverCAN = 0;
-            }
+            }*/
             if(sensors_scan_mode){ // sleep until next measurement start
                 if(Tms - lastSensT > SLEEP_TIME){
                     Sstate = SENS_START_MSRMNT;
+                    mesg("SENS_SLEEPING -> SENS_START_MSRMNT");
                 }
             }
         break;
diff --git a/F0:F030,F042,F072/TSYS_controller/tsys01.bin b/F0:F030,F042,F072/TSYS_controller/tsys01.bin
index 3fde223..e7a9af5 100755
Binary files a/F0:F030,F042,F072/TSYS_controller/tsys01.bin and b/F0:F030,F042,F072/TSYS_controller/tsys01.bin differ
diff --git a/F0:F030,F042,F072/TSYS_controller/usart.c b/F0:F030,F042,F072/TSYS_controller/usart.c
index 4f018ce..a08409d 100644
--- a/F0:F030,F042,F072/TSYS_controller/usart.c
+++ b/F0:F030,F042,F072/TSYS_controller/usart.c
@@ -29,6 +29,7 @@
 #include "usb.h"
 #endif
 
+#define WAITFOR (72000000)
 
 extern volatile uint32_t Tms;
 static int datalen[2] = {0,0}; // received data line length (including '\n')
@@ -62,14 +63,14 @@ TXstatus usart_send(const char *str, int len){
     if(!txrdy) return LINE_BUSY;
     if(len > UARTBUFSZ) return STR_TOO_LONG;
     txrdy = 0;
-    IWDG->KR = IWDG_REFRESH;
 #ifdef EBUG
     USB_send("\n\n\nUSART send:\n");
     USB_send(str);
     USB_send("\n\n");
 #endif
     memcpy(tbuf, str, len);
-    while(!(USARTX->ISR & USART_ISR_TXE)); // no refresh of WD to prevent weird things
+    for(int i = 0; (i < WAITFOR) && !(USARTX->ISR & USART_ISR_TXE); ++i){IWDG->KR = IWDG_REFRESH;}
+    if(!(USARTX->ISR & USART_ISR_TXE)) return LINE_BUSY;
 #if USARTNUM == 2
     DMA1_Channel4->CCR &= ~DMA_CCR_EN;
     DMA1_Channel4->CNDTR = len;
@@ -80,25 +81,32 @@ TXstatus usart_send(const char *str, int len){
     DMA1_Channel2->CCR |= DMA_CCR_EN;
 #else
 #error "Not implemented"
+#endif
+#ifdef EBUG
+    USB_send("    -> start transmission\n");
 #endif
     return ALL_OK;
 }
 
 TXstatus usart_send_blocking(const char *str, int len){
     if(!txrdy) return LINE_BUSY;
-    int i;
     bufovr = 0;
     IWDG->KR = IWDG_REFRESH;
-    while(!(USARTX->ISR & USART_ISR_TXE)); // no refresh of WD to prevent weird things
+    for(int i = 0; (i < WAITFOR) && !(USARTX->ISR & USART_ISR_TXE); ++i){IWDG->KR = IWDG_REFRESH;}
+    if(!(USARTX->ISR & USART_ISR_TXE)) return LINE_BUSY;
 #ifdef EBUG
     USB_send("\n\n\nUSART send blocking:\n");
     USB_send(str);
-    USB_send("\n\n");
+    USB_send("\n");
 #endif
-    for(i = 0; i < len; ++i){
+    for(int l = 0; l < len; ++l){
         USARTX -> TDR = *str++;
-        while(!(USARTX->ISR & USART_ISR_TXE)){IWDG->KR = IWDG_REFRESH;};
+        for(int i = 0; (i < WAITFOR) && !(USARTX->ISR & USART_ISR_TXE); ++i){IWDG->KR = IWDG_REFRESH;}
+        if(!(USARTX->ISR & USART_ISR_TXE)) return LINE_BUSY;
     }
+#ifdef EBUG
+    USB_send("    -> done\n");
+#endif
     return ALL_OK;
 }
 /*
@@ -135,7 +143,7 @@ void usart_setup(){
     USART2->BRR = 480000 / 1152;
     USART2->CR3 = USART_CR3_DMAT; // enable DMA Tx
     USART2->CR1 = USART_CR1_TE | USART_CR1_RE | USART_CR1_UE; // 1start,8data,nstop; enable Rx,Tx,USART
-    while(!(USART2->ISR & USART_ISR_TC)); // polling idle frame Transmission
+    for(int i = 0; (i < WAITFOR) && !(USART2->ISR & USART_ISR_TC); ++i){IWDG->KR = IWDG_REFRESH;} // polling idle frame Transmission
     USART2->ICR |= USART_ICR_TCCF; // clear TC flag
     USART2->CR1 |= USART_CR1_RXNEIE;
     NVIC_EnableIRQ(USART2_IRQn);
@@ -159,7 +167,7 @@ void usart_setup(){
     USART1->BRR = 480000 / 1152;
     USART1->CR3 = USART_CR3_DMAT; // enable DMA Tx
     USART1->CR1 = USART_CR1_TE | USART_CR1_RE | USART_CR1_UE; // 1start,8data,nstop; enable Rx,Tx,USART
-    while(!(USART1->ISR & USART_ISR_TC)); // polling idle frame Transmission
+    for(int i = 0; (i < WAITFOR) && !(USART1->ISR & USART_ISR_TC); ++i){IWDG->KR = IWDG_REFRESH;} // polling idle frame Transmission
     USART1->ICR |= USART_ICR_TCCF; // clear TC flag
     USART1->CR1 |= USART_CR1_RXNEIE;
     NVIC_EnableIRQ(USART1_IRQn);
diff --git a/F0:F030,F042,F072/TSYS_controller/version.inc b/F0:F030,F042,F072/TSYS_controller/version.inc
index 339b156..f662976 100644
--- a/F0:F030,F042,F072/TSYS_controller/version.inc
+++ b/F0:F030,F042,F072/TSYS_controller/version.inc
@@ -1,3 +1,3 @@
-#define BUILD_NUMBER "66"
-#define BUILD_DATE "2023-09-11"
-#define BUILDNO 66
+#define BUILD_NUMBER "80"
+#define BUILD_DATE "2023-09-12"
+#define BUILDNO 80