diff --git a/F0-nolib/Readme.md b/F0-nolib/Readme.md
index 8c3bf0b..cc0c969 100644
--- a/F0-nolib/Readme.md
+++ b/F0-nolib/Readme.md
@@ -14,6 +14,7 @@ This directory contains examples for F0 without any library
 - QuadEncoder - sample code for working with quadrature encoder (via timer)
 - Servo - simple servo (like SG-90) controller
 - Snippets - some small code snippets
+- Socket_fans - fan manager
 - TM1637 - work with 7-segment LED indicators based on TM1637
 - tsys01_nucleo - read two TSYS01 sensors using STM32F042
 - uart - USART over DMA with hardware end-of-string detection
@@ -22,3 +23,4 @@ This directory contains examples for F0 without any library
 - uart_nucleo - USART over DMA for STM32F042-nucleo
 - usbcan - USB<>CAN bridge using PL2303 emulation
 - USBHID - USB HID keyboard + mouse
+- USB_pl2303_snippet - full minimal snippet of PL2303 emulation for STM32F072xB
diff --git a/F1-nolib/CDC_ACM/Makefile_old b/F1-nolib/CDC_ACM/Makefile_old
deleted file mode 100644
index 66de9fb..0000000
--- a/F1-nolib/CDC_ACM/Makefile_old
+++ /dev/null
@@ -1,139 +0,0 @@
-BINARY		= cdcacm
-BOOTPORT	?= /dev/ttyUSB0
-BOOTSPEED	?= 115200
-# MCU FAMILY
-FAMILY		?= F1
-# MCU code
-MCU			?= F103x8
-# density (stm32f10x.h, lines 70-84)
-DENSITY 	?= MD
-# change this linking script depending on particular MCU model,
-LDSCRIPT	?= stm32f103x8.ld
-# debug
-#DEFS		= -DEBUG
-
-INDEPENDENT_HEADERS=
-
-FP_FLAGS	?= -msoft-float -mfloat-abi=soft
-ASM_FLAGS	?= -mthumb -mcpu=cortex-m3 -mfix-cortex-m3-ldrd
-ARCH_FLAGS	= $(ASM_FLAGS) $(FP_FLAGS)
-
-###############################################################################
-# Executables
-#PREFIX		?= arm-none-eabi
-# gcc from arm web site 
-PREFIX		?= /opt/bin/arm-none-eabi
-TOOLCHLIB	?= /opt/arm-none-eabi/lib
-RM			:= rm -f
-RMDIR		:= rmdir
-CC			:= $(PREFIX)-gcc
-# don't replace ld with gcc: the binary size would be much greater!!
-LD			:= $(PREFIX)-ld
-AR			:= $(PREFIX)-ar
-AS			:= $(PREFIX)-as
-SIZE 		:= $(PREFIX)-size
-OBJCOPY		:= $(PREFIX)-objcopy
-OBJDUMP		:= $(PREFIX)-objdump
-GDB			:= $(PREFIX)-gdb
-STFLASH		:= $(shell which st-flash)
-STBOOT		:= $(shell which stm32flash)
-DFUUTIL		:= $(shell which dfu-util)
-
-###############################################################################
-# Source files
-OBJDIR 		= mk
-SRC			:= $(wildcard *.c)
-OBJS		:= $(addprefix $(OBJDIR)/, $(SRC:%.c=%.o))
-STARTUP		= $(OBJDIR)/startup.o
-OBJS 		+= $(STARTUP)
-# dependencies: we need them to recompile files if their headers-dependencies changed
-DEPS		:= $(OBJS:.o=.d)
-
-INC_DIR ?= ../inc
-
-INCLUDE 	:= -I$(INC_DIR)/Fx -I$(INC_DIR)/cm
-LIB_DIR		:= $(INC_DIR)/ld
-
-###############################################################################
-# C flags
-CFLAGS		+= -O2 -g -D__thumb2__=1 -MD
-CFLAGS		+= -Wall -Werror -Wextra -Wshadow 
-CFLAGS		+= -fno-common -ffunction-sections -fdata-sections -fno-stack-protector
-CFLAGS		+=  $(ARCH_FLAGS)
-
-###############################################################################
-# Linker flags
-LDFLAGS		+= -nostartfiles --static -nostdlibs 
-LDFLAGS		+= -L$(LIB_DIR) -L$(TOOLCHLIB)
-LDFLAGS		+= -T$(LDSCRIPT)
-
-###############################################################################
-# Used libraries
-LDLIBS		+=  -lc $(shell $(CC) $(CFLAGS) -print-libgcc-file-name)
-
-PLATFRM		?= -DSTM32$(FAMILY) -DSTM32$(MCU) -DSTM32F10X_$(DENSITY)
-
-ELF		:= $(OBJDIR)/$(BINARY).elf
-LIST	:= $(OBJDIR)/$(BINARY).list
-BIN		:= $(BINARY).bin
-HEX		:= $(BINARY).hex
-
-all: bin list size
-
-elf: $(ELF)
-bin: $(BIN)
-hex: $(HEX)
-list: $(LIST)
-
-ifneq ($(MAKECMDGOALS),clean)
--include $(DEPS)
-endif
-
-$(OBJDIR):
-	mkdir $(OBJDIR)
-
-$(STARTUP): $(INC_DIR)/startup/vector.c
-	$(CC) $(CFLAGS) $(DEFS) $(PLATFRM) $(INCLUDE) -o $@ -c $<
-
-$(OBJDIR)/%.o: %.c
-	@echo "  CC      $<"
-	$(CC) $(CFLAGS) $(DEFS) $(PLATFRM) $(INCLUDE) -o $@ -c $<
-
-$(BIN): $(ELF)
-	@echo "  OBJCOPY $(BIN)"
-	$(OBJCOPY) -Obinary $(ELF) $(BIN)
-
-$(HEX): $(ELF)
-	@echo "  OBJCOPY $(HEX)"
-	$(OBJCOPY) -Oihex $(ELF) $(HEX)
-
-$(LIST): $(ELF)
-	@echo "  OBJDUMP $(LIST)"
-	$(OBJDUMP) -S $(ELF) > $(LIST)
-
-$(ELF): $(OBJDIR) $(OBJS)
-	@echo "  LD      $(ELF)"
-	$(LD) $(LDFLAGS) $(OBJS) $(LDLIBS) -o $(ELF)
-
-size: $(ELF)
-	$(SIZE) $(ELF)    
-
-clean:
-	@echo "  CLEAN"
-	$(RM) $(OBJS) $(DEPS) $(ELF) $(HEX) $(LIST)
-	@rmdir $(OBJDIR) 2>/dev/null || true
-
-
-flash: $(BIN)
-	@echo "  FLASH  $(BIN)"
-	$(STFLASH) write $(BIN) 0x8000000
-
-boot: $(BIN)
-	@echo "  LOAD $(BIN) through bootloader"
-	$(STBOOT) -b$(BOOTSPEED) $(BOOTPORT) -w $(BIN)
-
-dfuboot: $(BIN)
-	@echo "  LOAD  $(BIN) THROUGH DFU"
-	$(DFUUTIL) -a0 -D $(BIN) -s 0x08000000
-
-.PHONY: clean flash boot
diff --git a/F1-nolib/CDC_ACM/Readme b/F1-nolib/CDC_ACM/Readme
new file mode 100644
index 0000000..a96839b
--- /dev/null
+++ b/F1-nolib/CDC_ACM/Readme
@@ -0,0 +1 @@
+Base CDC snippet
diff --git a/F1-nolib/CDC_ACM/cdcacm.bin b/F1-nolib/CDC_ACM/cdcacm.bin
index 46c7c54..cf38f7d 100755
Binary files a/F1-nolib/CDC_ACM/cdcacm.bin and b/F1-nolib/CDC_ACM/cdcacm.bin differ
diff --git a/F1-nolib/CDC_ACM/hardware.c b/F1-nolib/CDC_ACM/hardware.c
index 0132ea2..e7b6442 100644
--- a/F1-nolib/CDC_ACM/hardware.c
+++ b/F1-nolib/CDC_ACM/hardware.c
@@ -23,6 +23,12 @@
 
 #include "hardware.h"
 
+// pause in milliseconds for some purposes
+void pause_ms(uint32_t pause){
+    uint32_t Tnxt = Tms + pause;
+    while(Tms < Tnxt) nop();
+}
+
 static inline void gpio_setup(){
     // Enable clocks to the GPIO subsystems (PB for ADC), turn on AFIO clocking to disable SWD/JTAG
     RCC->APB2ENR |= RCC_APB2ENR_IOPAEN | RCC_APB2ENR_IOPCEN | RCC_APB2ENR_AFIOEN;
diff --git a/F1-nolib/CDC_ACM/hardware.h b/F1-nolib/CDC_ACM/hardware.h
index 4115a34..465f8a4 100644
--- a/F1-nolib/CDC_ACM/hardware.h
+++ b/F1-nolib/CDC_ACM/hardware.h
@@ -40,6 +40,9 @@
 #define LED_on(x)       pin_clear(x ## _port, x ## _pin)
 #define LED_off(x)      pin_set(x ## _port, x ## _pin)
 
+extern volatile uint32_t Tms;
+
+void pause_ms(uint32_t pause);
 void hw_setup();
 
 #endif // __HARDWARE_H__
diff --git a/F1-nolib/CDC_ACM/main.c b/F1-nolib/CDC_ACM/main.c
index 4e24697..a74f585 100644
--- a/F1-nolib/CDC_ACM/main.c
+++ b/F1-nolib/CDC_ACM/main.c
@@ -20,7 +20,7 @@
  */
 
 #include "hardware.h"
-#include "usart.h"
+#include "proto.h"
 #include "usb.h"
 #include "usb_lib.h"
 
@@ -53,81 +53,41 @@ void iwdg_setup(){
     while(IWDG->SR){if(--tmout == 0) break;} /* (5) */
     IWDG->KR = IWDG_REFRESH; /* (6) */
 }
-/*
-char *parse_cmd(char *buf){
-    IWDG->KR = IWDG_REFRESH;
-    if(buf[1] != '\n') return buf;
-    switch(*buf){
-        case 'p':
-            pin_toggle(USBPU_port, USBPU_pin);
-            USB_send("USB pullup is ");
-            if(pin_read(USBPU_port, USBPU_pin)) USB_send("off\n");
-            else USB_send("on\n");
-            return NULL;
-        break;
-        case 'L':
-            USB_send("Very long test string for USB (it's length is more than 64 bytes).\n"
-                     "This is another part of the string! Can you see all of this?\n");
-            return "OK\n";
-        break;
-        case 'R':
-            USB_send("Soft reset\n");
-            NVIC_SystemReset();
-        break;
-        case 'S':
-            USB_send("Test string for USB\n");
-            return "OK\n";
-        break;
-        case 'W':
-            USB_send("Wait for reboot\n");
-            while(1){nop();};
-        break;
-        default: // help
-            return
-            "'p' - toggle USB pullup\n"
-            "'L' - send long string over USB\n"
-            "'R' - software reset\n"
-            "'S' - send short string over USB\n"
-            "'W' - test watchdog\n"
-            ;
-        break;
-    }
-    return NULL;
-}*/
-
-/*
-char *get_USB(){
-    static char tmpbuf[65];
-    int x = USB_receive(tmpbuf, 64);
-    tmpbuf[x] = 0;
-    if(!x) return NULL;
-    return tmpbuf;
-}
 
+#define USBBUF 63
 // usb getline
-char *get_USB(){
-    static char tmpbuf[128], *curptr = tmpbuf;
-    static int rest = 127;
-    int x = USB_receive(curptr, rest);
-    curptr[x] = 0;
+static char *get_USB(){
+    static char tmpbuf[USBBUF+1], *curptr = tmpbuf;
+    static int rest = USBBUF;
+    uint8_t x = USB_receive((uint8_t*)curptr);
     if(!x) return NULL;
-    if(curptr[x-1] == '\n'){
-        //DBG("Got \\n");
+    curptr[x] = 0;
+    if(x == 1 && *curptr == 0x7f){ // backspace
+        if(curptr > tmpbuf){
+            --curptr;
+            USND("\b \b");
+        }
+        return NULL;
+    }
+    USB_sendstr(curptr); // echo
+    if(curptr[x-1] == '\n'){ // || curptr[x-1] == '\r'){
         curptr = tmpbuf;
-        rest = 127;
+        rest = USBBUF;
+        // omit empty lines
+        if(tmpbuf[0] == '\n') return NULL;
+        // and wrong empty lines
+        if(tmpbuf[0] == '\r' && tmpbuf[1] == '\n') return NULL;
         return tmpbuf;
     }
     curptr += x; rest -= x;
     if(rest <= 0){ // buffer overflow
-        //DBG("Buffer full");
         curptr = tmpbuf;
-        rest = 127;
-        return tmpbuf;
+        rest = USBBUF;
     }
     return NULL;
-}*/
-
+}
 
+/* - these functions need for true USB-TTY
 static uint32_t newrate = 0;
 // redefine weak handlers
 void linecoding_handler(usb_LineCoding *lcd){
@@ -140,21 +100,6 @@ void clstate_handler(uint16_t val){
 static int8_t br = 0;
 void break_handler(){
     br = 1;
-}
-/*
-char *u2str(uint32_t val){
-    static char strbuf[11];
-    char *bufptr = &strbuf[10];
-    *bufptr = 0;
-    if(!val){
-        *(--bufptr) = '0';
-    }else{
-        while(val){
-            *(--bufptr) = val % 10 + '0';
-            val /= 10;
-        }
-    }
-    return bufptr;
 }*/
 
 int main(void){
@@ -162,54 +107,39 @@ int main(void){
     sysreset();
     StartHSE();
     SysTick_Config(72000);
-
     hw_setup();
+
     USBPU_OFF();
-    usart_setup();
-    DBG("Start");
-    if(RCC->CSR & RCC_CSR_IWDGRSTF){ // watchdog reset occured
+/*    if(RCC->CSR & RCC_CSR_IWDGRSTF){ // watchdog reset occured
         SEND("WDGRESET=1"); newline();
     }
     if(RCC->CSR & RCC_CSR_SFTRSTF){ // software reset occured
         SEND("SOFTRESET=1"); newline();
-    }
+    }*/
     RCC->CSR |= RCC_CSR_RMVF; // remove reset flags
 
     USB_setup();
     iwdg_setup();
     USBPU_ON();
 
-    //uint32_t ctr = 0;
     while (1){
         IWDG->KR = IWDG_REFRESH; // refresh watchdog
         if(Tms - lastT > 499){
             LED_blink(LED0);
             lastT = Tms;
-            transmit_tbuf();
         }
         usb_proc();
-        if(bufovr){
-            bufovr = 0;
-            USB_send((uint8_t*)"USART overflow!\n", 16);
-        }
-        uint8_t tmpbuf[USB_RXBUFSZ], *txt;
-        uint8_t x = USB_receive(tmpbuf);
-        if(x){
-            //for(int _ = 0; _ < 7000000; ++_)nop();
-            //USB_send(tmpbuf, x);
-            usart_senddata(tmpbuf, x);
-            //transmit_tbuf();
-           /*char *ans = parse_cmd(txt);
-           if(ans) USB_send(ans);*/
-        }
-        if((x = usart_get(&txt))){
-            USB_send(txt, x);
+        char *txt = get_USB();
+        if(txt){
+            IWDG->KR = IWDG_REFRESH;
+            cmd_parser(txt);
         }
+        /*
         int n = 0;
         if(newrate){SEND("new speed: "); printu(newrate); n = 1; newrate = 0;}
         if(cl!=0xffff){SEND("controls: "); printuhex(cl); n = 1; cl = 0xffff;}
         if(br){SEND("break"); n = 1; br = 0;}
-        if(n){newline(); transmit_tbuf();}
+        if(n){newline(); transmit_tbuf();}*/
     }
     return 0;
 }
diff --git a/F1-nolib/CDC_ACM/proto.c b/F1-nolib/CDC_ACM/proto.c
new file mode 100644
index 0000000..03108dd
--- /dev/null
+++ b/F1-nolib/CDC_ACM/proto.c
@@ -0,0 +1,205 @@
+/*
+ *                                                                                                  geany_encoding=koi8-r
+ * proto.c
+ *
+ * Copyright 2018 Edward V. Emelianov <eddy@sao.ru, edward.emelianoff@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ */
+#include "hardware.h"
+#include "proto.h"
+#include "usb.h"
+
+#include <string.h> // strlen
+
+static char buff[BUFSZ+1], *bptr = buff;
+static uint8_t blen = 0;
+
+void sendbuf(){
+    IWDG->KR = IWDG_REFRESH;
+    if(blen == 0) return;
+    *bptr = 0;
+    USB_sendstr(buff);
+    bptr = buff;
+    blen = 0;
+}
+
+void bufputchar(char ch){
+    if(blen > BUFSZ-1){
+        sendbuf();
+    }
+    *bptr++ = ch;
+    ++blen;
+}
+
+void addtobuf(const char *txt){
+    IWDG->KR = IWDG_REFRESH;
+    while(*txt) bufputchar(*txt++);
+}
+
+char *omit_spaces(char *buf){
+    while(*buf){
+        if(*buf > ' ') break;
+        ++buf;
+    }
+    return buf;
+}
+
+// THERE'S NO OVERFLOW PROTECTION IN NUMBER READ PROCEDURES!
+// read decimal number
+static char *getdec(char *buf, uint32_t *N){
+    uint32_t num = 0;
+    while(*buf){
+        char c = *buf;
+        if(c < '0' || c > '9'){
+            break;
+        }
+        num *= 10;
+        num += c - '0';
+        ++buf;
+    }
+    *N = num;
+    return buf;
+}
+// read hexadecimal number (without 0x prefix!)
+static char *gethex(char *buf, uint32_t *N){
+    uint32_t num = 0;
+    while(*buf){
+        char c = *buf;
+        uint8_t M = 0;
+        if(c >= '0' && c <= '9'){
+            M = '0';
+        }else if(c >= 'A' && c <= 'F'){
+            M = 'A' - 10;
+        }else if(c >= 'a' && c <= 'f'){
+            M = 'a' - 10;
+        }
+        if(M){
+            num <<= 4;
+            num += c - M;
+        }else{
+            break;
+        }
+        ++buf;
+    }
+    *N = num;
+    return buf;
+}
+// read binary number (without 0b prefix!)
+static char *getbin(char *buf, uint32_t *N){
+    uint32_t num = 0;
+    while(*buf){
+        char c = *buf;
+        if(c < '0' || c > '1'){
+            break;
+        }
+        num <<= 1;
+        if(c == '1') num |= 1;
+        ++buf;
+    }
+    *N = num;
+    return buf;
+}
+
+/**
+ * @brief getnum - read uint32_t from string (dec, hex or bin: 127, 0x7f, 0b1111111)
+ * @param buf - buffer with number and so on
+ * @param N   - the number read
+ * @return pointer to first non-number symbol in buf (if it is == buf, there's no number)
+ */
+char *getnum(char *txt, uint32_t *N){
+    if(*txt == '0'){
+        if(txt[1] == 'x' || txt[1] == 'X') return gethex(txt+2, N);
+        if(txt[1] == 'b' || txt[1] == 'B') return getbin(txt+2, N);
+    }
+    return getdec(txt, N);
+}
+
+/**
+ * @brief cmd_parser - command parsing
+ * @param txt   - buffer with commands & data
+ * @param isUSB - == 1 if data got from USB
+ */
+void cmd_parser(char *txt){
+    char _1st = txt[0];
+    /*
+     * parse long commands here
+     */
+    /*switch(_1st){
+        case 'a':
+            addIGN(txt + 1);
+            goto eof;
+        break;
+    }*/
+    if(txt[1] != '\n') *txt = '?'; // help for wrong message length
+    switch(_1st){
+        case 'R':
+            SEND("Soft reset\n");
+            sendbuf();
+            pause_ms(5); // a little pause to transmit data
+            NVIC_SystemReset();
+        break;
+        case 'T':
+            SEND("Time (ms): ");
+            printu(Tms);
+            newline();
+        break;
+        default: // help
+            SEND(
+            "'R' - software reset\n"
+            "'T' - get time from start (ms)\n"
+            );
+        break;
+    }
+    newline();
+    sendbuf();
+}
+
+// print 32bit unsigned int
+void printu(uint32_t val){
+    char buf[11], *bufptr = &buf[10];
+    *bufptr = 0;
+    if(!val){
+        *(--bufptr) = '0';
+    }else{
+        while(val){
+            *(--bufptr) = val % 10 + '0';
+            val /= 10;
+        }
+    }
+    addtobuf(bufptr);
+}
+
+// print 32bit unsigned int as hex
+void printuhex(uint32_t val){
+    addtobuf("0x");
+    uint8_t *ptr = (uint8_t*)&val + 3;
+    int8_t i, j, z=1;
+    for(i = 0; i < 4; ++i, --ptr){
+        if(*ptr == 0){ // omit leading zeros
+            if(i == 3) z = 0;
+            if(z) continue;
+        }
+        else z = 0;
+        for(j = 1; j > -1; --j){
+            uint8_t half = (*ptr >> (4*j)) & 0x0f;
+            if(half < 10) bufputchar(half + '0');
+            else bufputchar(half - 10 + 'a');
+        }
+    }
+}
+
diff --git a/F1-nolib/CDC_ACM/proto.h b/F1-nolib/CDC_ACM/proto.h
new file mode 100644
index 0000000..e979633
--- /dev/null
+++ b/F1-nolib/CDC_ACM/proto.h
@@ -0,0 +1,55 @@
+/*
+ *                                                                                                  geany_encoding=koi8-r
+ * proto.h
+ *
+ * Copyright 2018 Edward V. Emelianov <eddy@sao.ru, edward.emelianoff@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301, USA.
+ *
+ */
+#pragma once
+#ifndef __PROTO_H__
+#define __PROTO_H__
+
+#include "stm32f1.h"
+#include "hardware.h"
+
+#define BUFSZ   (64)
+
+// macro for static strings
+#define SEND(str) do{addtobuf(str);}while(0)
+
+#ifdef EBUG
+#define MSG(str)  do{addtobuf(__FILE__ " (L" STR(__LINE__) "): " str);}while(0)
+#else
+#define MSG(str)
+#endif
+
+#define newline() do{bufputchar('\n');}while(0)
+// newline with buffer sending over USART
+#define NL() do{bufputchar('\n'); sendbuf();}while(0)
+
+void cmd_parser(char *buf);
+void addtobuf(const char *txt);
+void bufputchar(char ch);
+void printu(uint32_t val);
+void printuhex(uint32_t val);
+void sendbuf();
+
+char *omit_spaces(char *buf);
+char *getnum(char *buf, uint32_t *N);
+
+#endif // __PROTO_H__
diff --git a/F1-nolib/CDC_ACM/usart.c b/F1-nolib/CDC_ACM/usart.c
deleted file mode 100644
index d631476..0000000
--- a/F1-nolib/CDC_ACM/usart.c
+++ /dev/null
@@ -1,265 +0,0 @@
-/*
- * usart.c
- *
- * Copyright 2018 Edward V. Emelianoff <eddy@sao.ru, edward.emelianoff@gmail.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02110-1301, USA.
- */
-#include "stm32f1.h"
-#include "usart.h"
-#include "usb.h"
-
-extern volatile uint32_t Tms;
-static volatile int idatalen[2] = {0,0}; // received data line length (including '\n')
-static volatile int odatalen[2] = {0,0};
-
-static int dlen = 0; // length of data (including '\n') in current buffer
-
-int linerdy = 0,        // received data ready
-    bufovr = 0,         // input buffer overfull
-    txrdy = 1           // transmission done
-;
-
-static int rbufno = 0, tbufno = 0; // current rbuf/tbuf numbers
-static uint8_t rbuf[2][UARTBUFSZI], tbuf[2][UARTBUFSZO]; // receive & transmit buffers
-static uint8_t *recvdata = NULL;
-
-/**
- * return length of received data (without trailing zero)
- */
-uint16_t usart_get(uint8_t **line){
-    if(!line) return 0;
-    *line = NULL;
-    if(bufovr){
-        bufovr = 0;
-        linerdy = 0;
-        return 0;
-    }
-    if(!linerdy) return 0;
-    USART1->CR1 &= ~USART_CR1_RXNEIE; // disallow Rx IRQ
-    dlen = idatalen[rbufno];
-    recvdata = rbuf[rbufno];
-    // prepare other buffer
-    rbufno = !rbufno;
-    idatalen[rbufno] = 0;
-    recvdata[dlen] = 0;
-    *line = recvdata;
-    linerdy = 0;
-    USART1->CR1 |= USART_CR1_RXNEIE; // allow Rx IRQ
-    return dlen;
-}
-
-// transmit current tbuf and swap buffers
-int transmit_tbuf(){
-    uint32_t tmout = 7200;
-    while(!txrdy){ // wait for previos buffer transmission
-        IWDG->KR = IWDG_REFRESH;
-        if(--tmout == 0){
-            //DMA1_Channel4->CCR &= ~DMA_CCR_EN;
-            //txrdy = 1;
-            return 1;
-        }
-    }
-    int l = odatalen[tbufno];
-    if(!l){
-        return 0;
-    }
-    DMA1_Channel4->CCR &= ~DMA_CCR_EN;
-    DMA1_Channel4->CMAR = (uint32_t) tbuf[tbufno]; // mem
-    DMA1_Channel4->CNDTR = l;
-    tbufno = !tbufno;
-    odatalen[tbufno] = 0;
-    txrdy = 0;
-    DMA1_Channel4->CCR |= DMA_CCR_EN;
-    return 0;
-}
-
-void usart_putchar(const char ch){
-    tbuf[tbufno][odatalen[tbufno]++] = ch;
-    if(odatalen[tbufno] >= UARTBUFSZO){
-        while(transmit_tbuf());
-    }
-}
-
-void usart_send(const char *str){
-    if(!str) return;
-    while(*str){
-        tbuf[tbufno][odatalen[tbufno]++] = *str++;
-        if(odatalen[tbufno] >= UARTBUFSZO){
-            while(transmit_tbuf());
-        }
-    }
-}
-
-/**
- * @brief usart_senddata - the same as usart_send, but with given length
- */
-void usart_senddata(const uint8_t *str, uint16_t len){
-    while(len--){
-        tbuf[tbufno][odatalen[tbufno]++] = *str++;
-        if(odatalen[tbufno] >= UARTBUFSZO){
-            while(transmit_tbuf());
-        }
-    }
-}
-
-void newline(){
-    usart_putchar('\n');
-}
-
-/*
- * USART speed: baudrate = Fck/(USARTDIV)
- * USARTDIV stored in USART->BRR
- *
- * for 72MHz USARTDIV=72000/f(kboud); so for 115200 USARTDIV=72000/115.2=625 -> BRR=0x271
- *         9600: BRR = 7500 (0x1D4C)
- */
-
-void usart_setup(){
-    uint32_t tmout = 16000000;
-    // PA9 - Tx, PA10 - Rx 
-    RCC->APB2ENR |= RCC_APB2ENR_IOPAEN | RCC_APB2ENR_USART1EN | RCC_APB2ENR_AFIOEN;
-    RCC->AHBENR |= RCC_AHBENR_DMA1EN;
-    GPIOA->CRH = CRH(9, CNF_AFPP|MODE_NORMAL) | CRH(10, CNF_FLINPUT|MODE_INPUT); 
-
-    // USART1 Tx DMA - Channel4 (Rx - channel 5)
-    DMA1_Channel4->CPAR = (uint32_t) &USART1->DR; // periph
-    DMA1_Channel4->CCR |= DMA_CCR_MINC | DMA_CCR_DIR | DMA_CCR_TCIE; // 8bit, mem++, mem->per, transcompl irq
-    // Tx CNDTR set @ each transmission due to data size
-    NVIC_SetPriority(DMA1_Channel4_IRQn, 3);
-    NVIC_EnableIRQ(DMA1_Channel4_IRQn);
-    NVIC_SetPriority(USART1_IRQn, 0);
-    // setup usart1
-    USART1->BRR = 72000000 / 115200;
-    //USART1->BRR = 24; // 3000000
-    USART1->CR1 = USART_CR1_TE | USART_CR1_RE | USART_CR1_UE; // 1start,8data,nstop; enable Rx,Tx,USART
-    while(!(USART1->SR & USART_SR_TC)){ // polling idle frame Transmission
-        IWDG->KR = IWDG_REFRESH;
-        if(--tmout == 0) break;
-    }
-    USART1->SR = 0; // clear flags
-    USART1->CR1 |= USART_CR1_RXNEIE; // allow Rx IRQ
-    USART1->CR3 = USART_CR3_DMAT; // enable DMA Tx
-    NVIC_EnableIRQ(USART1_IRQn);
-}
-
-
-void usart1_isr(){
-    #ifdef CHECK_TMOUT
-    static uint32_t tmout = 0;
-    #endif
-    if(USART1->SR & USART_SR_RXNE){ // RX not emty - receive next char
-        #ifdef CHECK_TMOUT
-        if(tmout && Tms >= tmout){ // set overflow flag
-            bufovr = 1;
-            idatalen[rbufno] = 0;
-        }
-        tmout = Tms + TIMEOUT_MS;
-        if(!tmout) tmout = 1; // prevent 0
-        #endif
-        uint8_t rb = USART1->DR;
-        if(idatalen[rbufno] < UARTBUFSZI){ // put next char into buf
-            rbuf[rbufno][idatalen[rbufno]++] = rb;
-            linerdy = 1; // ready for reading
-            #ifdef CHECK_TMOUT
-            // clear timeout at line end
-            tmout = 0;
-            #endif
-        }else{ // buffer overrun
-            bufovr = 1;
-            idatalen[rbufno] = 0;
-            #ifdef CHECK_TMOUT
-            tmout = 0;
-            #endif
-        }
-    }
-}
-
-
-// print 32bit unsigned int
-void printu(uint32_t val){
-    char bufa[11], bufb[10];
-    int l = 0, bpos = 0;
-    if(!val){
-        bufa[0] = '0';
-        l = 1;
-    }else{
-        while(val){
-            bufb[l++] = val % 10 + '0';
-            val /= 10;
-        }
-        int i;
-        bpos += l;
-        for(i = 0; i < l; ++i){
-            bufa[--bpos] = bufb[i];
-        }
-    }
-    bufa[l + bpos] = 0;
-    usart_send(bufa);
-}
-
-// print 32bit unsigned int as hex
-void printuhex(uint32_t val){
-    usart_send("0x");
-    uint8_t *ptr = (uint8_t*)&val + 3;
-    int i, j;
-    for(i = 0; i < 4; ++i, --ptr){
-        for(j = 1; j > -1; --j){
-            register uint8_t half = (*ptr >> (4*j)) & 0x0f;
-            if(half < 10) usart_putchar(half + '0');
-            else usart_putchar(half - 10 + 'a');
-        }
-    }
-}
-/*
-// dump memory buffer
-void hexdump(const uint8_t *arr, uint16_t len){
-    for(uint16_t l = 0; l < len; ++l, ++arr){
-        for(int16_t j = 1; j > -1; --j){
-            register uint8_t half = (*arr >> (4*j)) & 0x0f;
-            if(half < 10) usart_putchar(half + '0');
-            else usart_putchar(half - 10 + 'a');
-        }
-        if(l % 16 == 15) usart_putchar('\n');
-        else if(l & 1) usart_putchar(' ');
-    }
-}
-*/
-void dma1_channel4_isr(){
-    DMA1->IFCR = DMA_IFCR_CTCIF4; // clear TC flag
-    txrdy = 1;
-}
-
-/*
-#if USARTNUM == 2
-void dma1_channel4_5_isr(){
-    if(DMA1->ISR & DMA_ISR_TCIF4){ // Tx
-        DMA1->IFCR |= DMA_IFCR_CTCIF4; // clear TC flag
-        txrdy = 1;
-    }
-}
-// USART1
-#elif USARTNUM == 1
-void dma1_channel2_3_isr(){
-    if(DMA1->ISR & DMA_ISR_TCIF2){ // Tx
-        DMA1->IFCR |= DMA_IFCR_CTCIF2; // clear TC flag
-        txrdy = 1;
-    }
-}
-#else
-#error "Not implemented"
-#endif
-*/
diff --git a/F1-nolib/CDC_ACM/usart.h b/F1-nolib/CDC_ACM/usart.h
deleted file mode 100644
index e64ee73..0000000
--- a/F1-nolib/CDC_ACM/usart.h
+++ /dev/null
@@ -1,65 +0,0 @@
-/*
- * usart.h
- *
- * Copyright 2018 Edward V. Emelianoff <eddy@sao.ru, edward.emelianoff@gmail.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02110-1301, USA.
- */
-
-#pragma once
-#ifndef __USART_H__
-#define __USART_H__
-
-// input and output buffers size
-#define UARTBUFSZI  (64)
-#define UARTBUFSZO  (64)
-// timeout between data bytes
-#ifndef TIMEOUT_MS
-#define TIMEOUT_MS (1500)
-#endif
-
-// macro for static strings
-#define SEND(str) usart_send(str)
-#define _s(s)   #s
-#define STR(s)  _s(s)
-
-#ifdef EBUG
-#define DBG(str)  do{SEND(__FILE__ " (L" STR(__LINE__) "): " str); newline();}while(0)
-#define HERE()    do{SEND(STR(__LINE__)); usart_putchar('\n');}while(0)
-#define MSG(str)  do{SEND(str); usart_putchar('\n');}while(0)
-#else
-#define MSG(str)
-#define HERE()
-#define DBG(str)
-#endif
-
-#define usartrx()  (linerdy)
-#define usartovr() (bufovr)
-
-extern int linerdy, bufovr, txrdy;
-
-int transmit_tbuf();
-void usart_setup();
-uint16_t usart_get(uint8_t **line);
-void usart_send(const char *str);
-void usart_senddata(const uint8_t *str, uint16_t len);
-void newline();
-void usart_putchar(const char ch);
-void printu(uint32_t val);
-void printuhex(uint32_t val);
-void hexdump(const uint8_t *arr, uint16_t len);
-
-#endif // __USART_H__
diff --git a/F1-nolib/CDC_ACM/usb.c b/F1-nolib/CDC_ACM/usb.c
index 3af52c9..7d42861 100644
--- a/F1-nolib/CDC_ACM/usb.c
+++ b/F1-nolib/CDC_ACM/usb.c
@@ -22,34 +22,20 @@
  */
 #include "usb.h"
 #include "usb_lib.h"
-#include "usart.h"
 
 static volatile uint8_t tx_succesfull = 1;
-
-// interrupt IN handler (never used?)
-static void EP1_Handler(){
-    DBG("EP1");
-    uint16_t epstatus = KEEP_DTOG(USB->EPnR[1]);
-    if(RX_FLAG(epstatus)) epstatus = (epstatus & ~USB_EPnR_STAT_TX) ^ USB_EPnR_STAT_RX; // set valid RX
-    else epstatus = epstatus & ~(USB_EPnR_STAT_TX|USB_EPnR_STAT_RX);
-    // clear CTR
-    epstatus = (epstatus & ~(USB_EPnR_CTR_RX|USB_EPnR_CTR_TX));
-    USB->EPnR[1] = epstatus;
-}
-
-// data IN/OUT handlers
-static void transmit_Handler(){ // EP3IN
-    tx_succesfull = 1;
-    uint16_t epstatus = KEEP_DTOG_STAT(USB->EPnR[3]);
-    // clear CTR keep DTOGs & STATs
-    USB->EPnR[3] = (epstatus & ~(USB_EPnR_CTR_TX)); // clear TX ctr
-}
-
 static uint8_t rxNE = 0;
-static void receive_Handler(){ // EP2OUT
-    rxNE = 1;
-    uint16_t epstatus = KEEP_DTOG_STAT(USB->EPnR[2]);
-    USB->EPnR[2] = (epstatus & ~(USB_EPnR_CTR_RX)); // clear RX ctr
+
+static void rxtx_Handler(){
+    uint16_t epstatus = KEEP_DTOG(USB->EPnR[1]);
+    if(RX_FLAG(epstatus)){
+        rxNE = 1;
+        epstatus = (epstatus & ~(USB_EPnR_STAT_TX|USB_EPnR_CTR_RX)) ^ USB_EPnR_STAT_RX; // keep stat Tx & set valid RX, clear CTR Rx
+    }else{
+        tx_succesfull = 1;
+        epstatus = (epstatus & ~(USB_EPnR_STAT_TX|USB_EPnR_CTR_TX)) ^ USB_EPnR_STAT_RX; // keep stat Tx & set valid RX, clear CTR Tx
+    }
+    USB->EPnR[1] = epstatus;
 }
 
 void USB_setup(){
@@ -64,21 +50,21 @@ void USB_setup(){
     USB->ISTR   = 0;
     USB->CNTR   = USB_CNTR_RESETM | USB_CNTR_WKUPM; // allow only wakeup & reset interrupts
     NVIC_EnableIRQ(USB_LP_CAN1_RX0_IRQn);
-    DBG("USB irq enabled");
 }
 
+
 static int usbwr(const uint8_t *buf, uint16_t l){
     uint32_t ctra = 1000000;
     while(--ctra && tx_succesfull == 0){
         IWDG->KR = IWDG_REFRESH;
     }
     tx_succesfull = 0;
-    EP_Write(3, buf, l);
+    EP_Write(1, buf, l);
     ctra = 1000000;
     while(--ctra && tx_succesfull == 0){
         IWDG->KR = IWDG_REFRESH;
     }
-    if(tx_succesfull == 0){usbON = 0; DBG("USB disconnected"); return 1;} // usb is OFF?
+    if(tx_succesfull == 0){usbON = 0; return 1;} // usb is OFF?
     return 0;
 }
 
@@ -89,7 +75,7 @@ static uint8_t buflen = 0; // amount of symbols in usbbuff
 static void send_next(){
     if(!buflen || !tx_succesfull) return;
     tx_succesfull = 0;
-    EP_Write(3, usbbuff, buflen);
+    EP_Write(1, usbbuff, buflen);
     buflen = 0;
 }
 
@@ -107,6 +93,14 @@ void USB_send(const uint8_t *buf, uint16_t len){
     while(len--) usbbuff[buflen++] = *buf++;
 }
 
+// send zero-terminated string
+void USB_sendstr(const char *str){
+    uint16_t l = 0;
+    const char *ptr = str;
+    while(*ptr++) ++l;
+    USB_send((uint8_t*)str, l);
+}
+
 // blocking sending
 void USB_send_blk(const uint8_t *buf, uint16_t len){
     if(!usbON || !len) return; // USB disconnected
@@ -132,16 +126,13 @@ void usb_proc(){
         case USB_STATE_CONFIGURED:
             // make new BULK endpoint
             // Buffer have 1024 bytes, but last 256 we use for CAN bus (30.2 of RM: USB main features)
-            EP_Init(1, EP_TYPE_INTERRUPT, USB_EP1BUFSZ, 0, EP1_Handler); // IN1 - transmit
-            EP_Init(2, EP_TYPE_BULK, 0, USB_RXBUFSZ, receive_Handler); // OUT2 - receive data
-            EP_Init(3, EP_TYPE_BULK, USB_TXBUFSZ, 0, transmit_Handler); // IN3 - transmit data
+            //EP_Init(1, EP_TYPE_INTERRUPT, USB_EP1BUFSZ, 0, EP1_Handler); // IN1 - transmit
+            EP_Init(1, EP_TYPE_BULK, USB_TXBUFSZ, USB_RXBUFSZ, rxtx_Handler); // INOUT1 - transmit/receive data
             USB_Dev.USB_Status = USB_STATE_CONNECTED;
-            DBG("Connected");
         break;
         case USB_STATE_DEFAULT:
         case USB_STATE_ADDRESSED:
             if(usbON){
-                DBG("def/adr");
                 usbON = 0;
             }
         break;
@@ -158,11 +149,10 @@ void usb_proc(){
  */
 uint8_t USB_receive(uint8_t *buf){
     if(!usbON || !rxNE) return 0;
-    //DBG("Get data");
-    uint8_t sz = EP_Read(2, (uint16_t*)buf);
-    uint16_t epstatus = KEEP_DTOG(USB->EPnR[2]);
+    uint8_t sz = EP_Read(1, (uint16_t*)buf);
+    uint16_t epstatus = KEEP_DTOG(USB->EPnR[1]);
     // keep stat_tx & set ACK rx
-    USB->EPnR[2] = (epstatus & ~(USB_EPnR_STAT_TX)) ^ USB_EPnR_STAT_RX;
+    USB->EPnR[1] = (epstatus & ~(USB_EPnR_STAT_TX)) ^ USB_EPnR_STAT_RX;
     rxNE = 0;
     return sz;
 }
diff --git a/F1-nolib/CDC_ACM/usb.h b/F1-nolib/CDC_ACM/usb.h
index c9d315d..3c191ef 100644
--- a/F1-nolib/CDC_ACM/usb.h
+++ b/F1-nolib/CDC_ACM/usb.h
@@ -26,9 +26,13 @@
 
 #include "hardware.h"
 
+// send string with constant length
+#define USND(str)  do{USB_send((uint8_t*)str, sizeof(str)-1);}while(0)
+
 void USB_setup();
 void usb_proc();
 void USB_send(const uint8_t *buf, uint16_t len);
+void USB_sendstr(const char *str);
 void USB_send_blk(const uint8_t *buf, uint16_t len);
 uint8_t USB_receive(uint8_t *buf);
 
diff --git a/F1-nolib/CDC_ACM/usb_lib.c b/F1-nolib/CDC_ACM/usb_lib.c
index a25a31d..190ddd2 100644
--- a/F1-nolib/CDC_ACM/usb_lib.c
+++ b/F1-nolib/CDC_ACM/usb_lib.c
@@ -22,7 +22,6 @@
  */
 
 #include <stdint.h>
-#include "usart.h"
 #include "usb_lib.h"
 
 ep_t endpoints[STM32ENDPOINTS];
@@ -88,9 +87,7 @@ static const uint8_t USB_ConfigDescriptor[] = {
     0x00, /* iConfiguration: Index of string descriptor describing the configuration */
     0x80, /* bmAttributes - Bus powered */
     0x32, /* MaxPower 100 mA */
-
     /*---------------------------------------------------------------------------*/
-
     /*Interface Descriptor */
     0x09, /* bLength: Interface Descriptor size */
     0x04, /* bDescriptorType: Interface */
@@ -101,44 +98,38 @@ static const uint8_t USB_ConfigDescriptor[] = {
     0x02, /* bInterfaceSubClass: Abstract Control Model */
     0x01, /* bInterfaceProtocol: Common AT commands */
     0x00, /* iInterface: */
-
     /*Header Functional Descriptor*/
     0x05, /* bLength: Endpoint Descriptor size */
     0x24, /* bDescriptorType: CS_INTERFACE */
     0x00, /* bDescriptorSubtype: Header Func Desc */
     0x10, /* bcdCDC: spec release number */
     0x01,
-
     /*Call Management Functional Descriptor*/
     0x05, /* bFunctionLength */
     0x24, /* bDescriptorType: CS_INTERFACE */
     0x01, /* bDescriptorSubtype: Call Management Func Desc */
     0x00, /* bmCapabilities: D0+D1 */
     0x01, /* bDataInterface: 1 */
-
     /*ACM Functional Descriptor*/
     0x04, /* bFunctionLength */
     0x24, /* bDescriptorType: CS_INTERFACE */
     0x02, /* bDescriptorSubtype: Abstract Control Management desc */
     0x02, /* bmCapabilities */
-
     /*Union Functional Descriptor*/
     0x05, /* bFunctionLength */
     0x24, /* bDescriptorType: CS_INTERFACE */
     0x06, /* bDescriptorSubtype: Union func desc */
     0x00, /* bMasterInterface: Communication class interface */
     0x01, /* bSlaveInterface0: Data Class Interface */
-
     /*Endpoint 1 Descriptor*/
     0x07, /* bLength: Endpoint Descriptor size */
     0x05, /* bDescriptorType: Endpoint */
-    0x81, /* bEndpointAddress IN1 */
+    0x8A, /* bEndpointAddress IN10 */
     0x03, /* bmAttributes: Interrupt */
     (USB_EP1BUFSZ & 0xff), /* wMaxPacketSize LO: */
     (USB_EP1BUFSZ >> 8), /* wMaxPacketSize HI: */
     0x10, /* bInterval: */
     /*---------------------------------------------------------------------------*/
-
     /*Data class interface descriptor*/
     0x09, /* bLength: Endpoint Descriptor size */
     0x04, /* bDescriptorType: */
@@ -149,20 +140,18 @@ static const uint8_t USB_ConfigDescriptor[] = {
     0x02, /* bInterfaceSubClass: */
     0x00, /* bInterfaceProtocol: */
     0x00, /* iInterface: */
-
     /*Endpoint IN3 Descriptor*/
     0x07, /* bLength: Endpoint Descriptor size */
     0x05, /* bDescriptorType: Endpoint */
-    0x83, /* bEndpointAddress IN3 */
+    0x81, /* bEndpointAddress: IN1 */
     0x02, /* bmAttributes: Bulk */
     (USB_TXBUFSZ & 0xff), /* wMaxPacketSize: 64 */
     (USB_TXBUFSZ >> 8),
     0x00, /* bInterval: ignore for Bulk transfer */
-
-    /*Endpoint OUT2 Descriptor*/
+    /*Endpoint OUT1 Descriptor*/
     0x07, /* bLength: Endpoint Descriptor size */
     0x05, /* bDescriptorType: Endpoint */
-    0x02, /* bEndpointAddress */
+    0x01, /* bEndpointAddress: OUT1 */
     0x02, /* bmAttributes: Bulk */
     (USB_TXBUFSZ & 0xff), /* wMaxPacketSize: 64 */
     (USB_TXBUFSZ >> 8),
@@ -181,17 +170,17 @@ USB_STRING(USB_StringProdDescriptor, u"USB-Serial Controller");
  */
 // SET_LINE_CODING
 void WEAK linecoding_handler(usb_LineCoding __attribute__((unused)) *lcd){
-    MSG("linecoding_handler()");
+    //MSG("linecoding_handler()");
 }
 
 // SET_CONTROL_LINE_STATE
 void WEAK clstate_handler(uint16_t __attribute__((unused)) val){
-    MSG("clstate_handler()");
+    //MSG("clstate_handler()");
 }
 
 // SEND_BREAK
 void WEAK break_handler(){
-    MSG("break_handler()");
+    //MSG("break_handler()");
 }
 
 static void wr0(const uint8_t *buf, uint16_t size){
@@ -225,35 +214,27 @@ static void wr0(const uint8_t *buf, uint16_t size){
 static inline void get_descriptor(){
     switch(setup_packet.wValue){
         case DEVICE_DESCRIPTOR:
-            //MSG("DEVICE_D");
             wr0(USB_DeviceDescriptor, sizeof(USB_DeviceDescriptor));
         break;
         case CONFIGURATION_DESCRIPTOR:
-            //MSG("CONF_D");
             wr0(USB_ConfigDescriptor, sizeof(USB_ConfigDescriptor));
         break;
         case STRING_LANG_DESCRIPTOR:
-            //MSG("S_L_D");
             wr0((const uint8_t *)&USB_StringLangDescriptor, STRING_LANG_DESCRIPTOR_SIZE_BYTE);
         break;
         case STRING_MAN_DESCRIPTOR:
-            //MSG("S_M_D");
             wr0((const uint8_t *)&USB_StringManufacturingDescriptor, USB_StringManufacturingDescriptor.bLength);
         break;
         case STRING_PROD_DESCRIPTOR:
-            //MSG("S_P_D");
             wr0((const uint8_t *)&USB_StringProdDescriptor, USB_StringProdDescriptor.bLength);
         break;
         case STRING_SN_DESCRIPTOR:
-            //MSG("S_SN_D");
             wr0((const uint8_t *)&USB_StringSerialDescriptor, USB_StringSerialDescriptor.bLength);
         break;
         case DEVICE_QUALIFIER_DESCRIPTOR:
-            //MSG("D_Q_D");
             wr0(USB_DeviceQualifierDescriptor, USB_DeviceQualifierDescriptor[0]);
         break;
         default:
-            DBG("WTF?");
         break;
     }
 }
@@ -266,15 +247,12 @@ static inline void std_d2h_req(){
             get_descriptor();
         break;
         case GET_STATUS:
-            //MSG("GET_STAT");
             EP_WriteIRQ(0, (uint8_t *)&state, 2); // send status: Bus Powered
         break;
         case GET_CONFIGURATION:
-            //MSG("GET_CONF");
             EP_WriteIRQ(0, &configuration, 1);
         break;
         default:
-            DBG("WTF?");
         break;
     }
 }
@@ -282,18 +260,15 @@ static inline void std_d2h_req(){
 static inline void std_h2d_req(){
     switch(setup_packet.bRequest){
         case SET_ADDRESS:
-            //MSG("SET_ADDR");
             // new address will be assigned later - after  acknowlegement or request to host
             USB_Dev.USB_Addr = setup_packet.wValue;
         break;
         case SET_CONFIGURATION:
-            //MSG("SET_CONF");
             // Now device configured
             USB_Dev.USB_Status = USB_STATE_CONFIGURED;
             configuration = setup_packet.wValue;
         break;
         default:
-            DBG("WTF?");
         break;
     }
 }
@@ -315,7 +290,6 @@ static void EP0_Handler(){
     if(rxflag && SETUP_FLAG(epstatus)){
         switch(reqtype){
             case STANDARD_DEVICE_REQUEST_TYPE: // standard device request
-                //DBG("SDRT");
                 if(dev2host){
                     std_d2h_req();
                 }else{
@@ -324,43 +298,33 @@ static void EP0_Handler(){
                 }
             break;
             case STANDARD_ENDPOINT_REQUEST_TYPE: // standard endpoint request
-                //DBG("SERT");
                 if(setup_packet.bRequest == CLEAR_FEATURE){
-                    //MSG("CLEAR_F");
                     EP_WriteIRQ(0, (uint8_t *)0, 0);
                 }else{
-                    DBG("WTF?");
                 }
             break;
             case CONTROL_REQUEST_TYPE:
-                //DBG("CRT");
                 switch(setup_packet.bRequest){
                     case GET_LINE_CODING:
-                        //MSG("GET_LINE_C");
                         EP_WriteIRQ(0, (uint8_t*)&lineCoding, sizeof(lineCoding));
                     break;
                     case SET_LINE_CODING: // omit this for next stage, when data will come
-                        //MSG("SET_LINE_C");
                     break;
                     case SET_CONTROL_LINE_STATE:
-                        //MSG("SET_CLS");
                         usbON = 1;
                         clstate_handler(setup_packet.wValue);
                     break;
                     case SEND_BREAK:
-                        //MSG("SEND_BREAK");
                         usbON = 0;
                         break_handler();
                     break;
                     default:
-                        DBG("WTF?");
                     break;
                 }
                 if(setup_packet.bRequest != GET_LINE_CODING) EP_WriteIRQ(0, (uint8_t *)0, 0);
             break;
             default:
                 EP_WriteIRQ(0, (uint8_t *)0, 0);
-                DBG("WTF?");
         }
     }else if(rxflag){ // got data over EP0 or host acknowlegement
         if(endpoints[0].rx_cnt){
@@ -374,7 +338,6 @@ static void EP0_Handler(){
             USB->DADDR = USB_DADDR_EF | USB_Dev.USB_Addr;
             // change state to ADRESSED
             USB_Dev.USB_Status = USB_STATE_ADDRESSED;
-            //DBG("Addressed");
         }
     }
     epstatus = KEEP_DTOG(USB->EPnR[0]);
@@ -424,7 +387,6 @@ int EP_Init(uint8_t number, uint8_t type, uint16_t txsz, uint16_t rxsz, void (*f
 // standard IRQ handler
 void usb_lp_can_rx0_isr(){
     if(USB->ISTR & USB_ISTR_RESET){
-        //DBG("USB reset");
         usbON = 0;
         // Reinit registers
         USB->CNTR = USB_CNTR_RESETM | USB_CNTR_CTRM | USB_CNTR_SUSPM | USB_CNTR_WKUPM;
@@ -466,13 +428,11 @@ void usb_lp_can_rx0_isr(){
         if(endpoints[n].func) endpoints[n].func(endpoints[n]);
     }
     if(USB->ISTR & USB_ISTR_SUSP){ // suspend -> still no connection, may sleep
-        //DBG("USB suspend");
         usbON = 0;
         USB->CNTR |= USB_CNTR_FSUSP | USB_CNTR_LP_MODE;
         USB->ISTR = ~USB_ISTR_SUSP;
     }
     if(USB->ISTR & USB_ISTR_WKUP){ // wakeup
-        //DBG("USB wakeup");
         USB->CNTR &= ~(USB_CNTR_FSUSP | USB_CNTR_LP_MODE); // clear suspend flags
         USB->ISTR = ~USB_ISTR_WKUP;
     }