diff --git a/F0:F030,F042,F072/usbcan_ringbuffer/Makefile.old b/F0:F030,F042,F072/usbcan_ringbuffer/Makefile.old
deleted file mode 100644
index a997924..0000000
--- a/F0:F030,F042,F072/usbcan_ringbuffer/Makefile.old
+++ /dev/null
@@ -1,161 +0,0 @@
-BINARY		= usbcan
-BOOTPORT	?= /dev/ttyUSB0
-BOOTSPEED	?= 115200
-INDEPENDENT_HEADERS=
-# MCU FAMILY
-FAMILY		?= F0
-# MCU code
-MCU			?= F042x6
-# change this linking script depending on particular MCU model,
-LDSCRIPT	?= stm32f042x6.ld
-#DEFS = -DEBUG
-
-# autoincremental version & build date
-VERSION_FILE = version.inc
-ifeq ($(shell test -e $(VERSION_FILE) && echo -n yes), yes)
-	NEXTVER := $(shell expr $$(awk '/#define BUILD_NUMBER/' $(VERSION_FILE) | tr -cd "[0-9]") + 1)
-else
-	NEXTVER := "1"
-endif
-
-BUILDDATE := $(shell date +%Y-%m-%d)
-
-FP_FLAGS	?= -msoft-float
-# -mfloat-abi=soft
-ASM_FLAGS	?= -mthumb -mcpu=cortex-m0 -march=armv6-m -mtune=cortex-m0
-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
-LD			:= $(PREFIX)-gcc
-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)
-MAP			= $(OBJDIR)/$(BINARY).map
-# 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 -MD -D__thumb2__=1 
-CFLAGS		+= -Wall -Werror -Wextra -Wshadow -Wimplicit-function-declaration -Wredundant-decls
-CFLAGS		+= -fno-common -ffunction-sections -fdata-sections
-# -fno-stack-protector -fshort-enums
-CFLAGS		+=  $(ARCH_FLAGS) $(INCLUDE)
-
-###############################################################################
-# Linker flags
-LDFLAGS		+= -nostartfiles --static -Wl,--print-memory-usage
-# --specs=nano.specs -nostdlib
-LDFLAGS		+= -Wl,-Map=$(MAP) -Wl,--gc-sections
-LDFLAGS		+= -L$(LIB_DIR) -L$(TOOLCHLIB)
-LDFLAGS		+= -T$(LDSCRIPT) $(ARCH_FLAGS)
-
-###############################################################################
-# Used libraries
-LDLIBS		+= -Wl,--start-group -lc -lgcc -Wl,--end-group $(shell $(CC) $(CFLAGS) -print-libgcc-file-name)
-
-DEFS		+= -DSTM32$(FAMILY) -DSTM32$(MCU)
-
-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) $(INCLUDE) -o $@ -c $<
-
-$(VERSION_FILE): *.[ch]
-	[ -f $(VERSION_FILE) ] || echo -e "#define BUILD_NUMBER \"0\"\n#define BUILD_DATE \"none\"" > $(VERSION_FILE)
-	@echo "  Generate version: $(NEXTVER) for date $(BUILDDATE)"
-	@sed -i "s/#define BUILD_NUMBER.*/#define BUILD_NUMBER \"$(NEXTVER)\"/" $(VERSION_FILE)
-	@sed -i "s/#define BUILD_DATE.*/#define BUILD_DATE \"$(BUILDDATE)\"/" $(VERSION_FILE)
-
-$(OBJDIR)/proto.o: proto.c $(VERSION_FILE)
-
-$(OBJDIR)/%.o: %.c
-	@echo "  CC      $<"
-	$(CC) $(CFLAGS) $(DEFS) $(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) $(MAP)
-	@rmdir $(OBJDIR) 2>/dev/null || true
-
-flash: $(BIN)
-	@echo "  FLASH  $(BIN)"
-	$(STFLASH) --reset 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
-
-openocd:
-	openocd -f openocd.cfg 
-dbg:
-	arm-none-eabi-gdb $(ELF) -ex 'target remote localhost:3333' -ex 'monitor reset halt'
-
-.PHONY: clean flash boot dfuboot size dbg openocd
diff --git a/F0:F030,F042,F072/usbcan_ringbuffer/Readme.md b/F0:F030,F042,F072/usbcan_ringbuffer/Readme.md
index 21afa5d..68d36ad 100644
--- a/F0:F030,F042,F072/usbcan_ringbuffer/Readme.md
+++ b/F0:F030,F042,F072/usbcan_ringbuffer/Readme.md
@@ -7,4 +7,4 @@ PB1 - LED1 - shine when line OK
 
 PB8, PB9 - CAN Rx/Tx
 
-PA11. PA12 - USB DM/DP
+PA11, PA12 - USB DM/DP
diff --git a/F0:F030,F042,F072/usbcan_ringbuffer/proto.c b/F0:F030,F042,F072/usbcan_ringbuffer/proto.c
index e177ab7..e5f5da2 100644
--- a/F0:F030,F042,F072/usbcan_ringbuffer/proto.c
+++ b/F0:F030,F042,F072/usbcan_ringbuffer/proto.c
@@ -427,7 +427,7 @@ static void add_filter(char *str){
 }
 
 const char *helpmsg =
-    "https://github.com/eddyem/stm32samples/tree/master/F0-nolib/usbcan_ringbuffer build#" BUILD_NUMBER " @ " BUILD_DATE "\n"
+    "https://github.com/eddyem/stm32samples/tree/master/F0-nolib/usbcan_ringbuffer " RLSDBG " build #" BUILD_NUMBER "@" BUILD_DATE "\n"
     "'a' - add ID to ignore list (max 10 IDs)\n"
     "'b' - reinit CAN with given baudrate\n"
     "'c' - get CAN status\n"
diff --git a/F0:F030,F042,F072/usbcan_ringbuffer/proto.h b/F0:F030,F042,F072/usbcan_ringbuffer/proto.h
index 5feb1df..91846ee 100644
--- a/F0:F030,F042,F072/usbcan_ringbuffer/proto.h
+++ b/F0:F030,F042,F072/usbcan_ringbuffer/proto.h
@@ -23,10 +23,11 @@
 
 #define BUFSZ   (64)
 
+// DEBUG/RELEASE build
 #ifdef EBUG
-#define DBG(str)  do{USB_sendstr(__FILE__ " (L" STR(__LINE__) "): " str);}while(0)
+#define RLSDBG "debug"
 #else
-#define DBG(str)
+#define RLSDBG "release"
 #endif
 
 #define IGN_SIZE 10
diff --git a/F0:F030,F042,F072/usbcan_ringbuffer/usbcan.bin b/F0:F030,F042,F072/usbcan_ringbuffer/usbcan.bin
index b8c99a2..2fd182c 100755
Binary files a/F0:F030,F042,F072/usbcan_ringbuffer/usbcan.bin and b/F0:F030,F042,F072/usbcan_ringbuffer/usbcan.bin differ
diff --git a/F0:F030,F042,F072/usbcan_ringbuffer/version.inc b/F0:F030,F042,F072/usbcan_ringbuffer/version.inc
index 9445724..a7bef25 100644
--- a/F0:F030,F042,F072/usbcan_ringbuffer/version.inc
+++ b/F0:F030,F042,F072/usbcan_ringbuffer/version.inc
@@ -1,2 +1,2 @@
-#define BUILD_NUMBER "34"
-#define BUILD_DATE "2023-04-11"
+#define BUILD_NUMBER "35"
+#define BUILD_DATE "2024-07-02"