Hallo
Gleiche Problem ?
alle float's werden auf dem NIBO-Grafikdisplay als ? ausgegeben.
Beispiel 8 von der NIBO-Anleitung finktioniert auch nicht:

float volt = 0.0166 * bot_supply - 1.19;
sprintf(text, "%3.1fV", (double)volt);
gfx_move(30, 10);
gfx_print_text(text);

Kann Jemand helfen ?
Danke

hier MakeFile (AVR-Studio)

## General Flags
PROJECT = TEST_01
MCU = atmega128
TARGET = TEST_01.elf
CC = avr-gcc

CPP = avr-g++

## Options common to compile, link and assembly rules
COMMON = -mmcu=$(MCU)

## Compile options common for all C compilation units.
CFLAGS = $(COMMON)
CFLAGS += -Wall -gdwarf-2 -std=gnu99 -D_NIBO_2_ -wl,-u,vfprintf -DF_CPU=16000000UL -Os -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
CFLAGS += -MD -MP -MT $(*F).o -MF dep/$(@F).d

## Assembly specific flags
ASMFLAGS = $(COMMON)
ASMFLAGS += $(CFLAGS)
ASMFLAGS += -x assembler-with-cpp -Wa,-gdwarf2

## Linker flags
LDFLAGS = $(COMMON)
LDFLAGS += -Wl,-Map=TEST_01.map


## Intel Hex file production flags
HEX_FLASH_FLAGS = -R .eeprom -R .fuse -R .lock -R .signature

HEX_EEPROM_FLAGS = -j .eeprom
HEX_EEPROM_FLAGS += --set-section-flags=.eeprom="alloc,load"
HEX_EEPROM_FLAGS += --change-section-lma .eeprom=0 --no-change-warnings


## Include Directories
INCLUDES = -I"C:\Programme\Atmel\NiboLib\include"

## Library Directories
LIBDIRS = -L"C:\Programme\Atmel\NiboLib\lib"

## Libraries
LIBS = -lnibo2 -lm -lprintf_flt

## Objects that must be built in order to link
OBJECTS = TEST_08.o

## Objects explicitly added by the user
LINKONLYOBJECTS =

## Build
all: $(TARGET) TEST_01.hex TEST_01.eep TEST_01.lss size

## Compile
TEST_08.o: ../TEST_08.c
$(CC) $(INCLUDES) $(CFLAGS) -c $<

##Link
$(TARGET): $(OBJECTS)
$(CC) $(LDFLAGS) $(OBJECTS) $(LINKONLYOBJECTS) $(LIBDIRS) $(LIBS) -o $(TARGET)

%.hex: $(TARGET)
avr-objcopy -O ihex $(HEX_FLASH_FLAGS) $< $@

%.eep: $(TARGET)
-avr-objcopy $(HEX_EEPROM_FLAGS) -O ihex $< $@ || exit 0

%.lss: $(TARGET)
avr-objdump -h -S $< > $@

size: ${TARGET}
@echo
@avr-size -C --mcu=${MCU} ${TARGET}

## Clean target
.PHONY: clean
clean:
-rm -rf $(OBJECTS) TEST_01.elf dep/* TEST_01.hex TEST_01.eep TEST_01.lss TEST_01.map


## Other dependencies
-include $(shell mkdir dep 2>NUL) $(wildcard dep/*)