Analog Digital Umwandlung, einstiegs Code.

#include <avr/io.h> //Defines pins, ports, etc.

#include <util/delay.h>

static inline void initADC0(void) {

  ADMUX |= (1 << REFS0); //reference voltage on AVCC

  //ADCSRA |= (1 << ADPS1) | (1 << ADPS0); //ADC clock prescaler /8

    ADCSRA |= (1 << ADPS1) | (1 << ADPS2); //ADC clock prescaler /64

  ADCSRA |= (1 << ADEN); //enables the ADC

}

int main(void) {

  uint16_t potentiometerValue;

  uint16_t threshold_level;

  threshold_level= 0b10000000;

  DDRD |= (1 << PD7); //Data Direction Register B: writing a 1 to the bit enables output

  initADC0();

  while (1) {

    ADCSRA |= (1 << ADSC); //start ADC conversion

    loop_until_bit_is_clear(ADCSRA, ADSC); //wait until ADC conversion is done

    potentiometerValue= ADC; //read ADC value in

    if (potentiometerValue > threshold_level) {

      PORTD= 0b10000000; //turn on LED attached to port PB0

    }

    else {

      PORTD= 0b00000000; //turn off LED attached to port PB0

    }

      return (0); //this line is never actually reached

    }

}

# Hey Emacs, this is a -*- makefile -*-

#

# WinAVR makefile written by Eric B. Weddington, J�rg Wunsch, et al.

# Released to the Public Domain

# Please read the make user manual!

#

# Additional material for this makefile was submitted by:

#  Tim Henigan

#  Peter Fleury

#  Reiner Patommel

#  Sander Pool

#  Frederik Rouleau

#  Markus Pfaff

#

# On command line:

#

# make all = Make software.

#

# make clean = Clean out built project files.

#

# make coff = Convert ELF to AVR COFF (for use with AVR Studio 3.x or VMLAB).

#

# make extcoff = Convert ELF to AVR Extended COFF (for use with AVR Studio

#                4.07 or greater).

#

# make program = Download the hex file to the device, using avrdude.  Please

#                customize the avrdude settings below first!

#

# make filename.s = Just compile filename.c into the assembler code only

#

# To rebuild project do "make clean" then "make all".

#

# mth 2004/09 

# Differences from WinAVR 20040720 sample:

# - DEPFLAGS according to Eric Weddingtion's fix (avrfreaks/gcc-forum)

# - F_OSC Define in CFLAGS and AFLAGS

# MCU name

#MCU = atmega168

DEVICE = atmega32

MCU = $(DEVICE)

# Main Oscillator Frequency

# This is only used to define F_OSC in all assembler and c-sources.

F_OSC = 8000000

F_CPU = $(F_OSC)

CFLAGS = -mmcu=$(DEVICE) -DF_CPU=$(F_CPU)

# Output format. (can be srec, ihex, binary)

FORMAT = ihex

# Target file name (without extension).

TARGET = poti

# List C source files here. (C dependencies are automatically generated.)

SRC = $(TARGET).c

# List Assembler source files here.

# Make them always end in a capital .S.  Files ending in a lowercase .s

# will not be considered source files but generated files (assembler

# output from the compiler), and will be deleted upon "make clean"!

# Even though the DOS/Win* filesystem matches both .s and .S the same,

# it will preserve the spelling of the filenames, and gcc itself does

# care about how the name is spelled on its command-line.

ASRC = 

# Optimization level, can be [0, 1, 2, 3, s]. 

# 0 = turn off optimization. s = optimize for size.

# (Note: 3 is not always the best optimization level. See avr-libc FAQ.)

OPT = s

# Debugging format.

# Native formats for AVR-GCC's -g are stabs [default], or dwarf-2.

# AVR (extended) COFF requires stabs, plus an avr-objcopy run.

#DEBUG = stabs

DEBUG = dwarf-2

# List any extra directories to look for include files here.

#     Each directory must be seperated by a space.

EXTRAINCDIRS = 

# Compiler flag to set the C Standard level.

# c89   - "ANSI" C

# gnu89 - c89 plus GCC extensions

# c99   - ISO C99 standard (not yet fully implemented)

# gnu99 - c99 plus GCC extensions

CSTANDARD = -std=gnu99

# Place -D or -U options here

CDEFS =

# Place -I options here

CINCS =

# Compiler flags.

#  -g*:          generate debugging information

#  -O*:          optimization level

#  -f...:        tuning, see GCC manual and avr-libc documentation

#  -Wall...:     warning level

#  -Wa,...:      tell GCC to pass this to the assembler.

#    -adhlns...: create assembler listing

CFLAGS += -g$(DEBUG)

CFLAGS += $(CDEFS) $(CINCS)

CFLAGS += -O$(OPT)

CFLAGS += -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums

CFLAGS += -Wall -Wextra -Wstrict-prototypes

CFLAGS += -Wa,-adhlns=$(<:.c=.lst)

CFLAGS += $(patsubst %,-I%,$(EXTRAINCDIRS))

CFLAGS += $(CSTANDARD)

#CFLAGS += -DF_OSC=$(F_OSC)

# Assembler flags.

#  -Wa,...:   tell GCC to pass this to the assembler.

#  -ahlms:    create listing

#  -gstabs:   have the assembler create line number information; note that

#             for use in COFF files, additional information about filenames

#             and function names needs to be present in the assembler source

#             files -- see avr-libc docs [FIXME: not yet described there]

ASFLAGS = -Wa,-adhlns=$(<:.S=.lst),-gstabs 

ASFLAGS += -DF_OSC=$(F_OSC)

#Additional libraries.

# Minimalistic printf version

PRINTF_LIB_MIN = -Wl,-u,vfprintf -lprintf_min

# Floating point printf version (requires MATH_LIB = -lm below)

PRINTF_LIB_FLOAT = -Wl,-u,vfprintf -lprintf_flt

PRINTF_LIB = 

# Minimalistic scanf version

SCANF_LIB_MIN = -Wl,-u,vfscanf -lscanf_min

# Floating point + %[ scanf version (requires MATH_LIB = -lm below)

SCANF_LIB_FLOAT = -Wl,-u,vfscanf -lscanf_flt

SCANF_LIB = 

MATH_LIB = -lm

# External memory options

# 64 KB of external RAM, starting after internal RAM (ATmega128!),

# used for variables (.data/.bss) and heap (malloc()).

#EXTMEMOPTS = -Wl,-Tdata=0x801100,--defsym=__heap_end=0x80ffff

# 64 KB of external RAM, starting after internal RAM (ATmega128!),

# only used for heap (malloc()).

#EXTMEMOPTS = -Wl,--defsym=__heap_start=0x801100,--defsym=__heap_end=0x80ffff

EXTMEMOPTS =

# Linker flags.

#  -Wl,...:     tell GCC to pass this to linker.

#    -Map:      create map file

#    --cref:    add cross reference to  map file

LDFLAGS = -Wl,-Map=$(TARGET).map,--cref

LDFLAGS += $(EXTMEMOPTS)

LDFLAGS += $(PRINTF_LIB) $(SCANF_LIB) $(MATH_LIB)

# Programming support using avrdude. Settings and variables.

# Programming hardware: alf avr910 avrisp bascom bsd 

# dt006 pavr picoweb pony-stk200 sp12 stk200 stk500

#

# Type: avrdude -c ?

# to get a full listing.

#

AVRDUDE_PROGRAMMER = stk500

# com1 = serial port. Use lpt1 to connect to parallel port.

AVRDUDE_PORT = com1    # programmer connected to serial device

AVRDUDE_WRITE_FLASH = -U flash:w:$(TARGET).hex

#AVRDUDE_WRITE_EEPROM = -U eeprom:w:$(TARGET).eep

# Uncomment the following if you want avrdude's erase cycle counter.

# Note that this counter needs to be initialized first using -Yn,

# see avrdude manual.

#AVRDUDE_ERASE_COUNTER = -y

# Uncomment the following if you do /not/ wish a verification to be

# performed after programming the device.

#AVRDUDE_NO_VERIFY = -V

# Increase verbosity level.  Please use this when submitting bug

# reports about avrdude. See <http://savannah.nongnu.org/projects/avrdude> 

# to submit bug reports.

#AVRDUDE_VERBOSE = -v -v

AVRDUDE_FLAGS = -p $(MCU) -P $(AVRDUDE_PORT) -c $(AVRDUDE_PROGRAMMER)

AVRDUDE_FLAGS += $(AVRDUDE_NO_VERIFY)

AVRDUDE_FLAGS += $(AVRDUDE_VERBOSE)

AVRDUDE_FLAGS += $(AVRDUDE_ERASE_COUNTER)

# ---------------------------------------------------------------------------

# Define directories, if needed.

DIRAVR = c:/winavr

DIRAVRBIN = $(DIRAVR)/bin

DIRAVRUTILS = $(DIRAVR)/utils/bin

DIRINC = .

DIRLIB = $(DIRAVR)/avr/lib

# Define programs and commands.

SHELL = sh

CC = avr-gcc

OBJCOPY = avr-objcopy

OBJDUMP = avr-objdump

SIZE = avr-size

NM = avr-nm

AVRDUDE = avrdude

REMOVE = rm -f

COPY = cp

# Define Messages

# English

MSG_ERRORS_NONE = Errors: none

MSG_BEGIN = -------- begin --------

MSG_END = --------  end  --------

MSG_SIZE_BEFORE = Size before: 

MSG_SIZE_AFTER = Size after:

MSG_COFF = Converting to AVR COFF:

MSG_EXTENDED_COFF = Converting to AVR Extended COFF:

MSG_FLASH = Creating load file for Flash:

MSG_EEPROM = Creating load file for EEPROM:

MSG_EXTENDED_LISTING = Creating Extended Listing:

MSG_SYMBOL_TABLE = Creating Symbol Table:

MSG_LINKING = Linking:

MSG_COMPILING = Compiling:

MSG_ASSEMBLING = Assembling:

MSG_CLEANING = Cleaning project:

# Define all object files.

OBJ = $(SRC:.c=.o) $(ASRC:.S=.o) 

# Define all listing files.

LST = $(ASRC:.S=.lst) $(SRC:.c=.lst)

# Compiler flags to generate dependency files.

### GENDEPFLAGS = -Wp,-M,-MP,-MT,$(*F).o,-MF,.dep/$(@F).d

GENDEPFLAGS = -MD -MP -MF .dep/$(@F).d

# Combine all necessary flags and optional flags.

# Add target processor to flags.

ALL_CFLAGS = -mmcu=$(MCU) -I. $(CFLAGS) $(GENDEPFLAGS)

ALL_ASFLAGS = -mmcu=$(MCU) -I. -x assembler-with-cpp $(ASFLAGS)

# Default target.

all: begin gccversion sizebefore build sizeafter finished end

build: elf hex eep lss sym

elf: $(TARGET).elf

hex: $(TARGET).hex

eep: $(TARGET).eep

lss: $(TARGET).lss 

sym: $(TARGET).sym

# Eye candy.

# AVR Studio 3.x does not check make's exit code but relies on

# the following magic strings to be generated by the compile job.

begin:

  @echo

  @echo $(MSG_BEGIN)

finished:

  @echo $(MSG_ERRORS_NONE)

end:

  @echo $(MSG_END)

  @echo

# Display size of file.

HEXSIZE = $(SIZE) --target=$(FORMAT) $(TARGET).hex

ELFSIZE = $(SIZE) -A $(TARGET).elf

sizebefore:

  @if [ -f $(TARGET).elf ]; then echo; echo $(MSG_SIZE_BEFORE); $(ELFSIZE); echo; fi

sizeafter:

  @if [ -f $(TARGET).elf ]; then echo; echo $(MSG_SIZE_AFTER); $(ELFSIZE); echo; fi

# Display compiler version information.

gccversion : 

  @$(CC) --version

# Program the device.  

program: $(TARGET).hex $(TARGET).eep

  $(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH) $(AVRDUDE_WRITE_EEPROM)

# Convert ELF to COFF for use in debugging / simulating in AVR Studio or VMLAB.

COFFCONVERT=$(OBJCOPY) --debugging \

--change-section-address .data-0x800000 \

--change-section-address .bss-0x800000 \

--change-section-address .noinit-0x800000 \

--change-section-address .eeprom-0x810000 

coff: $(TARGET).elf

  @echo

  @echo $(MSG_COFF) $(TARGET).cof

  $(COFFCONVERT) -O coff-avr $< $(TARGET).cof

extcoff: $(TARGET).elf

  @echo

  @echo $(MSG_EXTENDED_COFF) $(TARGET).cof

  $(COFFCONVERT) -O coff-ext-avr $< $(TARGET).cof

# Create final output files (.hex, .eep) from ELF output file.

%.hex: %.elf

  @echo

  @echo $(MSG_FLASH) $@

  $(OBJCOPY) -O $(FORMAT) -R .eeprom $< $@

%.eep: %.elf

  @echo

  @echo $(MSG_EEPROM) $@

  -$(OBJCOPY) -j .eeprom --set-section-flags=.eeprom="alloc,load" \

  --change-section-lma .eeprom=0 -O $(FORMAT) $< $@

# Create extended listing file from ELF output file.

%.lss: %.elf

  @echo

  @echo $(MSG_EXTENDED_LISTING) $@

  $(OBJDUMP) -h -S $< > $@

# Create a symbol table from ELF output file.

%.sym: %.elf

  @echo

  @echo $(MSG_SYMBOL_TABLE) $@

  $(NM) -n $< > $@

# Link: create ELF output file from object files.

.SECONDARY : $(TARGET).elf

.PRECIOUS : $(OBJ)

%.elf: $(OBJ)

  @echo

  @echo $(MSG_LINKING) $@

  $(CC) $(ALL_CFLAGS) $(OBJ) --output $@ $(LDFLAGS)

# Compile: create object files from C source files.

%.o : %.c

  @echo

  @echo $(MSG_COMPILING) $<

  $(CC) -c $(ALL_CFLAGS) $< -o $@ 

# Compile: create assembler files from C source files.

%.s : %.c

  $(CC) -S $(ALL_CFLAGS) $< -o $@

# Assemble: create object files from assembler source files.

%.o : %.S

  @echo

  @echo $(MSG_ASSEMBLING) $<

  $(CC) -c $(ALL_ASFLAGS) $< -o $@

# Target: clean project.

clean: begin clean_list finished end

clean_list :

  @echo

  @echo $(MSG_CLEANING)

  $(REMOVE) $(TARGET).hex

  $(REMOVE) $(TARGET).eep

  $(REMOVE) $(TARGET).obj

  $(REMOVE) $(TARGET).cof

  $(REMOVE) $(TARGET).elf

  $(REMOVE) $(TARGET).map

  $(REMOVE) $(TARGET).obj

  $(REMOVE) $(TARGET).a90

  $(REMOVE) $(TARGET).sym

  $(REMOVE) $(TARGET).lnk

  $(REMOVE) $(TARGET).lss

  $(REMOVE) $(OBJ)

  $(REMOVE) $(LST)

  $(REMOVE) $(SRC:.c=.s)

  $(REMOVE) $(SRC:.c=.d)

  $(REMOVE) .dep/*

# Include the dependency files.

-include $(shell mkdir .dep 2>/dev/null) $(wildcard .dep/*)

# Listing of phony targets.

.PHONY : all begin finish end sizebefore sizeafter gccversion \

build elf hex eep lss sym coff extcoff \

clean clean_list program