Initial commit
This commit is contained in:
Mark Qvist
commit
05d62b594e
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@ -0,0 +1,379 @@
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|||
# AVR Sample makefile written by Eric B. Weddington, Jörg Wunsch, et al.
|
||||
# Modified (bringing often-changed options to the top) by Elliot Williams
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||||
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||||
# make all = Make software and program
|
||||
# make clean = Clean out built project files.
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||||
# make program = Download the hex file to the device, using avrdude. Please
|
||||
# customize the avrdude settings below first!
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||||
|
||||
# Microcontroller Type
|
||||
#MCU = atmega1284p
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||||
#MCU = atmega644p
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||||
MCU = atmega328p
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||||
|
||||
# Target file name (without extension).
|
||||
TARGET = images/OpenAPRS
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||||
|
||||
# Programming hardware: type avrdude -c ?
|
||||
# to get a full listing.
|
||||
AVRDUDE_PROGRAMMER = arduino
|
||||
|
||||
AVRDUDE_PORT = /dev/usb # not really needed for usb
|
||||
#AVRDUDE_PORT = /dev/parport0 # linux
|
||||
# AVRDUDE_PORT = lpt1 # windows
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||||
|
||||
############# Don't need to change below here for most purposes (Elliot)
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||||
|
||||
# Optimization level, can be [0, 1, 2, 3, s]. 0 turns off optimization.
|
||||
# (Note: 3 is not always the best optimization level. See avr-libc FAQ.)
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||||
OPT = s
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||||
|
||||
# Output format. (can be srec, ihex, binary)
|
||||
FORMAT = ihex
|
||||
|
||||
# List C source files here. (C dependencies are automatically generated.)
|
||||
#SRC = $(TARGET).c
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||||
SRC = main.c hardware/Serial.c hardware/AFSK.c util/CRC-CCIT.c protocol/AX25.c protocol/KISS.c
|
||||
|
||||
# If there is more than one source file, append them above, or modify and
|
||||
# uncomment the following:
|
||||
#SRC += foo.c bar.c
|
||||
|
||||
# You can also wrap lines by appending a backslash to the end of the line:
|
||||
#SRC += baz.c \
|
||||
#xyzzy.c
|
||||
|
||||
|
||||
|
||||
# List Assembler source files here.
|
||||
# Make them always end in a capital .S. Files ending in a lowercase .s
|
||||
# will not be considered source files but generated files (assembler
|
||||
# output from the compiler), and will be deleted upon "make clean"!
|
||||
# Even though the DOS/Win* filesystem matches both .s and .S the same,
|
||||
# it will preserve the spelling of the filenames, and gcc itself does
|
||||
# care about how the name is spelled on its command-line.
|
||||
ASRC =
|
||||
|
||||
|
||||
# List any extra directories to look for include files here.
|
||||
# Each directory must be seperated by a space.
|
||||
EXTRAINCDIRS =
|
||||
|
||||
|
||||
# Optional compiler flags.
|
||||
# -g: generate debugging information (for GDB, or for COFF conversion)
|
||||
# -O*: optimization level
|
||||
# -f...: tuning, see gcc manual and avr-libc documentation
|
||||
# -Wall...: warning level
|
||||
# -Wa,...: tell GCC to pass this to the assembler.
|
||||
# -ahlms: create assembler listing
|
||||
CFLAGS = -g -O$(OPT) \
|
||||
-funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums \
|
||||
-Wall -Wstrict-prototypes \
|
||||
-Wa,-adhlns=$(<:.c=.lst) \
|
||||
$(patsubst %,-I%,$(EXTRAINCDIRS))
|
||||
|
||||
|
||||
# Set a "language standard" compiler flag.
|
||||
# Unremark just one line below to set the language standard to use.
|
||||
# gnu99 = C99 + GNU extensions. See GCC manual for more information.
|
||||
#CFLAGS += -std=c89
|
||||
#CFLAGS += -std=gnu89
|
||||
#CFLAGS += -std=c99
|
||||
CFLAGS += -std=gnu99
|
||||
|
||||
|
||||
|
||||
# Optional 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=$(<:.S=.lst),-gstabs
|
||||
|
||||
|
||||
|
||||
# Optional linker flags.
|
||||
# -Wl,...: tell GCC to pass this to linker.
|
||||
# -Map: create map file
|
||||
# --cref: add cross reference to map file
|
||||
LDFLAGS = -Wl,-Map=$(TARGET).map,--cref
|
||||
|
||||
|
||||
|
||||
# Additional libraries
|
||||
|
||||
# Minimalistic printf version
|
||||
#LDFLAGS += -Wl,-u,vfprintf -lprintf_min
|
||||
|
||||
# Floating point printf version (requires -lm below)
|
||||
#LDFLAGS += -Wl,-u,vfprintf -lprintf_flt
|
||||
|
||||
# -lm = math library
|
||||
LDFLAGS += -lm
|
||||
|
||||
|
||||
# Programming support using avrdude. Settings and variables.
|
||||
|
||||
|
||||
AVRDUDE_WRITE_FLASH = -U flash:w:$(TARGET).hex
|
||||
#AVRDUDE_WRITE_EEPROM = -U eeprom:w:$(TARGET).eep
|
||||
|
||||
AVRDUDE_FLAGS = -p $(MCU) -P $(AVRDUDE_PORT) -c $(AVRDUDE_PROGRAMMER)
|
||||
|
||||
# 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 += -y
|
||||
|
||||
# Uncomment the following if you do /not/ wish a verification to be
|
||||
# performed after programming the device.
|
||||
#AVRDUDE_FLAGS += -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_FLAGS += -v -v
|
||||
|
||||
#Run while cable attached or don't
|
||||
AVRDUDE_FLAGS += -E reset #keep chip disabled while cable attached
|
||||
#AVRDUDE_FLAGS += -E noreset
|
||||
|
||||
#AVRDUDE_WRITE_FLASH = -U lfuse:w:0x04:m #run with 8 Mhz clock
|
||||
|
||||
#AVRDUDE_WRITE_FLASH = -U lfuse:w:0x21:m #run with 1 Mhz clock #default clock mode
|
||||
|
||||
#AVRDUDE_WRITE_FLASH = -U lfuse:w:0x01:m #run with 1 Mhz clock no start up time
|
||||
|
||||
# ---------------------------------------------------------------------------
|
||||
|
||||
# Define programs and commands.
|
||||
SHELL = sh
|
||||
|
||||
CC = avr-gcc
|
||||
|
||||
OBJCOPY = avr-objcopy
|
||||
OBJDUMP = avr-objdump
|
||||
SIZE = avr-size
|
||||
|
||||
|
||||
# Programming support using avrdude.
|
||||
AVRDUDE = avrdude
|
||||
|
||||
|
||||
REMOVE = rm -f
|
||||
COPY = cp
|
||||
|
||||
HEXSIZE = $(SIZE) --target=$(FORMAT) $(TARGET).hex
|
||||
ELFSIZE = $(SIZE) -C $(TARGET).elf
|
||||
|
||||
|
||||
|
||||
# Define Messages
|
||||
# English
|
||||
MSG_ERRORS_NONE = Firmware compiled successfully!
|
||||
MSG_BEGIN = Starting build...
|
||||
MSG_END = -------- Done --------
|
||||
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) $(SRC:.c=.lst)
|
||||
|
||||
# Combine all necessary flags and optional flags.
|
||||
# Add target processor to flags.
|
||||
ALL_CFLAGS = -mmcu=$(MCU) -I. $(CFLAGS)
|
||||
ALL_ASFLAGS = -mmcu=$(MCU) -I. -x assembler-with-cpp $(ASFLAGS)
|
||||
|
||||
|
||||
|
||||
# Default target: make program!
|
||||
#all: begin gccversion sizebefore $(TARGET).elf $(TARGET).hex $(TARGET).eep \
|
||||
# $(TARGET).lss $(TARGET).sym sizeafter finished end
|
||||
|
||||
all: begin $(TARGET).elf $(TARGET).hex $(TARGET).eep \
|
||||
$(TARGET).lss $(TARGET).sym cleanup sizeafter finished
|
||||
# $(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH) $(AVRDUDE_WRITE_EEPROM)
|
||||
|
||||
# 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.
|
||||
sizebefore:
|
||||
@if [ -f $(TARGET).elf ]; then echo; echo $(MSG_SIZE_BEFORE); $(ELFSIZE); echo; fi
|
||||
|
||||
sizeafter:
|
||||
@if [ -f $(TARGET).elf ]; then echo; $(ELFSIZE); echo; fi
|
||||
|
||||
|
||||
|
||||
# Display compiler version information.
|
||||
gccversion :
|
||||
@$(CC) --version
|
||||
|
||||
|
||||
|
||||
|
||||
# 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
|
||||
|
||||
|
||||
|
||||
|
||||
# Program the device.
|
||||
program: $(TARGET).hex $(TARGET).eep
|
||||
@$(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH) $(AVRDUDE_WRITE_EEPROM)
|
||||
|
||||
|
||||
|
||||
|
||||
# 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) $@
|
||||
# @echo Not generating any EEPROM images
|
||||
@-$(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) $@
|
||||
@avr-nm -n $< > $@
|
||||
|
||||
|
||||
|
||||
# Link: create ELF output file from object files.
|
||||
.SECONDARY : $(TARGET).elf
|
||||
.PRECIOUS : $(OBJ)
|
||||
%.elf: $(OBJ)
|
||||
@echo $(MSG_LINKING) $@
|
||||
@$(CC) $(ALL_CFLAGS) $(OBJ) --output $@ $(LDFLAGS)
|
||||
|
||||
|
||||
# Compile: create object files from C source files.
|
||||
%.o : %.c
|
||||
@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: clean_list finished
|
||||
|
||||
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)
|
||||
$(REMOVE) *~
|
||||
|
||||
cleanup:
|
||||
@$(REMOVE) $(SRC:.c=.s)
|
||||
@$(REMOVE) $(SRC:.c=.d)
|
||||
@$(REMOVE) $(LST)
|
||||
|
||||
# Automatically generate C source code dependencies.
|
||||
# (Code originally taken from the GNU make user manual and modified
|
||||
# (See README.txt Credits).)
|
||||
#
|
||||
# Note that this will work with sh (bash) and sed that is shipped with WinAVR
|
||||
# (see the SHELL variable defined above).
|
||||
# This may not work with other shells or other seds.
|
||||
#
|
||||
%.d: %.c
|
||||
@set -e; $(CC) -MM $(ALL_CFLAGS) $< \
|
||||
| sed 's,\(.*\)\.o[ :]*,\1.o \1.d : ,g' > $@; \
|
||||
[ -s $@ ] || rm -f $@
|
||||
|
||||
|
||||
# Remove the '-' if you want to see the dependency files generated.
|
||||
-include $(SRC:.c=.d)
|
||||
|
||||
|
||||
|
||||
# Listing of phony targets.
|
||||
.PHONY : all begin finish end sizebefore sizeafter gccversion coff extcoff \
|
||||
clean clean_list program
|
||||
|
|
@ -0,0 +1,20 @@
|
|||
#ifndef DEVICE_CONFIGURATION
|
||||
#define DEVICE_CONFIGURATION
|
||||
|
||||
// CPU settings
|
||||
#define F_CPU 16000000
|
||||
#define FREQUENCY_CORRECTION 0
|
||||
|
||||
// Sampling & timer setup
|
||||
#define CONFIG_AFSK_DAC_SAMPLERATE 9600
|
||||
|
||||
// Serial settings
|
||||
#define BAUD 9600
|
||||
|
||||
// Port settings
|
||||
#define DAC_PORT PORTB
|
||||
#define DAC_DDR DDRB
|
||||
#define ADC_PORT PORTC
|
||||
#define ADC_DDR DDRC
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,2 @@
|
|||
#!/bin/bash
|
||||
avrdude -p $2 -c arduino -P /dev/tty$1 -b 115200 -F -U flash:w:images/OpenAPRS.hex
|
||||
|
|
@ -0,0 +1,451 @@
|
|||
#include <string.h>
|
||||
#include "AFSK.h"
|
||||
#include "util/time.h"
|
||||
|
||||
extern volatile ticks_t _clock;
|
||||
extern unsigned long custom_preamble;
|
||||
extern unsigned long custom_tail;
|
||||
|
||||
bool hw_afsk_dac_isr = false;
|
||||
Afsk *AFSK_modem;
|
||||
|
||||
// Forward declerations
|
||||
int afsk_getchar(void);
|
||||
void afsk_putchar(char c);
|
||||
|
||||
void AFSK_hw_init(void) {
|
||||
// Disable interrupts while we set up everything
|
||||
cli();
|
||||
|
||||
// Set up ADC
|
||||
TCCR1A = 0;
|
||||
TCCR1B = _BV(CS10) | _BV(WGM13) | _BV(WGM12);
|
||||
ICR1 = (((CPU_FREQ+FREQUENCY_CORRECTION)) / 9600) - 1;
|
||||
|
||||
// TODO: Implement reference detection
|
||||
ADMUX = _BV(REFS0) | 0;
|
||||
ADC_DDR &= ~_BV(0);
|
||||
ADC_PORT &= ~_BV(0);
|
||||
DIDR0 |= _BV(0);
|
||||
ADCSRB = _BV(ADTS2) |
|
||||
_BV(ADTS1) |
|
||||
_BV(ADTS0);
|
||||
ADCSRA = _BV(ADEN) |
|
||||
_BV(ADSC) |
|
||||
_BV(ADATE)|
|
||||
_BV(ADIE) |
|
||||
_BV(ADPS2);
|
||||
|
||||
// Enable interrupts - starts DAC/ADC
|
||||
sei();
|
||||
AFSK_DAC_INIT();
|
||||
LED_TX_INIT();
|
||||
LED_RX_INIT();
|
||||
}
|
||||
|
||||
void AFSK_init(Afsk *afsk) {
|
||||
// Allocate modem struct memory
|
||||
memset(afsk, 0, sizeof(*afsk));
|
||||
AFSK_modem = afsk;
|
||||
// Set phase increment
|
||||
afsk->phaseInc = MARK_INC;
|
||||
// Initialise FIFO buffers
|
||||
fifo_init(&afsk->delayFifo, (uint8_t *)afsk->delayBuf, sizeof(afsk->delayBuf));
|
||||
fifo_init(&afsk->rxFifo, afsk->rxBuf, sizeof(afsk->rxBuf));
|
||||
fifo_init(&afsk->txFifo, afsk->txBuf, sizeof(afsk->txBuf));
|
||||
|
||||
// Set up streams
|
||||
FILE afsk_fd = FDEV_SETUP_STREAM(afsk_putchar, afsk_getchar, _FDEV_SETUP_RW);
|
||||
afsk->fd = afsk_fd;
|
||||
|
||||
AFSK_hw_init();
|
||||
}
|
||||
|
||||
static void AFSK_txStart(Afsk *afsk) {
|
||||
if (!afsk->sending) {
|
||||
afsk->phaseInc = MARK_INC;
|
||||
afsk->phaseAcc = 0;
|
||||
afsk->bitstuffCount = 0;
|
||||
afsk->sending = true;
|
||||
LED_TX_ON();
|
||||
afsk->preambleLength = DIV_ROUND(custom_preamble * BITRATE, 8000);
|
||||
AFSK_DAC_IRQ_START();
|
||||
}
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
afsk->tailLength = DIV_ROUND(custom_tail * BITRATE, 8000);
|
||||
}
|
||||
}
|
||||
|
||||
void afsk_putchar(char c) {
|
||||
AFSK_txStart(AFSK_modem);
|
||||
while(fifo_isfull_locked(&AFSK_modem->txFifo)) { /* Wait */ }
|
||||
fifo_push_locked(&AFSK_modem->txFifo, c);
|
||||
}
|
||||
|
||||
int afsk_getchar(void) {
|
||||
if (fifo_isempty_locked(&AFSK_modem->rxFifo)) {
|
||||
return EOF;
|
||||
} else {
|
||||
return fifo_pop_locked(&AFSK_modem->rxFifo);
|
||||
}
|
||||
}
|
||||
|
||||
void AFSK_transmit(char *buffer, size_t size) {
|
||||
fifo_flush(&AFSK_modem->txFifo);
|
||||
int i = 0;
|
||||
while (size--) {
|
||||
afsk_putchar(buffer[i++]);
|
||||
}
|
||||
}
|
||||
|
||||
uint8_t AFSK_dac_isr(Afsk *afsk) {
|
||||
if (afsk->sampleIndex == 0) {
|
||||
if (afsk->txBit == 0) {
|
||||
if (fifo_isempty(&afsk->txFifo) && afsk->tailLength == 0) {
|
||||
AFSK_DAC_IRQ_STOP();
|
||||
afsk->sending = false;
|
||||
LED_TX_OFF();
|
||||
return 0;
|
||||
} else {
|
||||
if (!afsk->bitStuff) afsk->bitstuffCount = 0;
|
||||
afsk->bitStuff = true;
|
||||
if (afsk->preambleLength == 0) {
|
||||
if (fifo_isempty(&afsk->txFifo)) {
|
||||
afsk->tailLength--;
|
||||
afsk->currentOutputByte = HDLC_FLAG;
|
||||
} else {
|
||||
afsk->currentOutputByte = fifo_pop(&afsk->txFifo);
|
||||
}
|
||||
} else {
|
||||
afsk->preambleLength--;
|
||||
afsk->currentOutputByte = HDLC_FLAG;
|
||||
}
|
||||
if (afsk->currentOutputByte == AX25_ESC) {
|
||||
if (fifo_isempty(&afsk->txFifo)) {
|
||||
AFSK_DAC_IRQ_STOP();
|
||||
afsk->sending = false;
|
||||
LED_TX_OFF();
|
||||
return 0;
|
||||
} else {
|
||||
afsk->currentOutputByte = fifo_pop(&afsk->txFifo);
|
||||
}
|
||||
} else if (afsk->currentOutputByte == HDLC_FLAG || afsk->currentOutputByte == HDLC_RESET) {
|
||||
afsk->bitStuff = false;
|
||||
}
|
||||
}
|
||||
afsk->txBit = 0x01;
|
||||
}
|
||||
|
||||
if (afsk->bitStuff && afsk->bitstuffCount >= BIT_STUFF_LEN) {
|
||||
afsk->bitstuffCount = 0;
|
||||
afsk->phaseInc = SWITCH_TONE(afsk->phaseInc);
|
||||
} else {
|
||||
if (afsk->currentOutputByte & afsk->txBit) {
|
||||
afsk->bitstuffCount++;
|
||||
} else {
|
||||
afsk->bitstuffCount = 0;
|
||||
afsk->phaseInc = SWITCH_TONE(afsk->phaseInc);
|
||||
}
|
||||
afsk->txBit <<= 1;
|
||||
}
|
||||
|
||||
afsk->sampleIndex = SAMPLESPERBIT;
|
||||
}
|
||||
|
||||
afsk->phaseAcc += afsk->phaseInc;
|
||||
afsk->phaseAcc %= SIN_LEN;
|
||||
afsk->sampleIndex--;
|
||||
|
||||
return sinSample(afsk->phaseAcc);
|
||||
}
|
||||
|
||||
static bool hdlcParse(Hdlc *hdlc, bool bit, FIFOBuffer *fifo) {
|
||||
// Initialise a return value. We start with the
|
||||
// assumption that all is going to end well :)
|
||||
bool ret = true;
|
||||
|
||||
// Bitshift our byte of demodulated bits to
|
||||
// the left by one bit, to make room for the
|
||||
// next incoming bit
|
||||
hdlc->demodulatedBits <<= 1;
|
||||
// And then put the newest bit from the
|
||||
// demodulator into the byte.
|
||||
hdlc->demodulatedBits |= bit ? 1 : 0;
|
||||
|
||||
// Now we'll look at the last 8 received bits, and
|
||||
// check if we have received a HDLC flag (01111110)
|
||||
if (hdlc->demodulatedBits == HDLC_FLAG) {
|
||||
// If we have, check that our output buffer is
|
||||
// not full.
|
||||
if (!fifo_isfull(fifo)) {
|
||||
// If it isn't, we'll push the HDLC_FLAG into
|
||||
// the buffer and indicate that we are now
|
||||
// receiving data. For bling we also turn
|
||||
// on the RX LED.
|
||||
fifo_push(fifo, HDLC_FLAG);
|
||||
hdlc->receiving = true;
|
||||
LED_RX_ON();
|
||||
} else {
|
||||
// If the buffer is full, we have a problem
|
||||
// and abort by setting the return value to msg.len = ctx->frm_len - 2 - (buf - ctx->buf);
|
||||
|
||||
// false and stopping the here.
|
||||
ret = false;
|
||||
hdlc->receiving = false;
|
||||
LED_RX_OFF();
|
||||
}
|
||||
|
||||
// Everytime we receive a HDLC_FLAG, we reset the
|
||||
// storage for our current incoming byte and bit
|
||||
// position in that byte. This effectively
|
||||
// synchronises our parsing to the start and end
|
||||
// of the received bytes.
|
||||
hdlc->currentByte = 0;
|
||||
hdlc->bitIndex = 0;
|
||||
return ret;
|
||||
}
|
||||
|
||||
// Check if we have received a RESET flag (01111111)
|
||||
// In this comparison we also detect when no transmission
|
||||
// (or silence) is taking place, and the demodulator
|
||||
// returns an endless stream of zeroes. Due to the NRZ
|
||||
// coding, the actual bits send to this function will
|
||||
// be an endless stream of ones, which this AND operation
|
||||
// will also detect.
|
||||
if ((hdlc->demodulatedBits & HDLC_RESET) == HDLC_RESET) {
|
||||
// If we have, something probably went wrong at the
|
||||
// transmitting end, and we abort the reception.
|
||||
hdlc->receiving = false;
|
||||
LED_RX_OFF();
|
||||
return ret;
|
||||
}
|
||||
|
||||
// If we have not yet seen a HDLC_FLAG indicating that
|
||||
// a transmission is actually taking place, don't bother
|
||||
// with anything.
|
||||
if (!hdlc->receiving)
|
||||
return ret;
|
||||
|
||||
// First check if what we are seeing is a stuffed bit.
|
||||
// Since the different HDLC control characters like
|
||||
// HDLC_FLAG, HDLC_RESET and such could also occur in
|
||||
// a normal data stream, we employ a method known as
|
||||
// "bit stuffing". All control characters have more than
|
||||
// 5 ones in a row, so if the transmitting party detects
|
||||
// this sequence in the _data_ to be transmitted, it inserts
|
||||
// a zero to avoid the receiving party interpreting it as
|
||||
// a control character. Therefore, if we detect such a
|
||||
// "stuffed bit", we simply ignore it and wait for the
|
||||
// next bit to come in.
|
||||
//
|
||||
// We do the detection by applying an AND bit-mask to the
|
||||
// stream of demodulated bits. This mask is 00111111 (0x3f)
|
||||
// if the result of the operation is 00111110 (0x3e), we
|
||||
// have detected a stuffed bit.
|
||||
if ((hdlc->demodulatedBits & 0x3f) == 0x3e)
|
||||
return ret;
|
||||
|
||||
// If we have an actual 1 bit, push this to the current byte
|
||||
// If it's a zero, we don't need to do anything, since the
|
||||
// bit is initialized to zero when we bitshifted earlier.
|
||||
if (hdlc->demodulatedBits & 0x01)
|
||||
hdlc->currentByte |= 0x80;
|
||||
|
||||
// Increment the bitIndex and check if we have a complete byte
|
||||
if (++hdlc->bitIndex >= 8) {
|
||||
// If we have a HDLC control character, put a AX.25 escape
|
||||
// in the received data. We know we need to do this,
|
||||
// because at this point we must have already seen a HDLC
|
||||
// flag, meaning that this control character is the result
|
||||
// of a bitstuffed byte that is equal to said control
|
||||
// character, but is actually part of the data stream.
|
||||
// By inserting the escape character, we tell the protocol
|
||||
// layer that this is not an actual control character, but
|
||||
// data.
|
||||
if ((hdlc->currentByte == HDLC_FLAG ||
|
||||
hdlc->currentByte == HDLC_RESET ||
|
||||
hdlc->currentByte == AX25_ESC)) {
|
||||
// We also need to check that our received data buffer
|
||||
// is not full before putting more data in
|
||||
if (!fifo_isfull(fifo)) {
|
||||
fifo_push(fifo, AX25_ESC);
|
||||
} else {
|
||||
// If it is, abort and return false
|
||||
hdlc->receiving = false;
|
||||
LED_RX_OFF();
|
||||
ret = false;
|
||||
}
|
||||
}
|
||||
|
||||
// Push the actual byte to the received data FIFO,
|
||||
// if it isn't full.
|
||||
if (!fifo_isfull(fifo)) {
|
||||
fifo_push(fifo, hdlc->currentByte);
|
||||
} else {
|
||||
// If it is, well, you know by now!
|
||||
hdlc->receiving = false;
|
||||
LED_RX_OFF();
|
||||
ret = false;
|
||||
}
|
||||
|
||||
// Wipe received byte and reset bit index to 0
|
||||
hdlc->currentByte = 0;
|
||||
hdlc->bitIndex = 0;
|
||||
|
||||
} else {
|
||||
// We don't have a full byte yet, bitshift the byte
|
||||
// to make room for the next bit
|
||||
hdlc->currentByte >>= 1;
|
||||
}
|
||||
|
||||
//digitalWrite(13, LOW);
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
void AFSK_adc_isr(Afsk *afsk, int8_t currentSample) {
|
||||
// To determine the received frequency, and thereby
|
||||
// the bit of the sample, we multiply the sample by
|
||||
// a sample delayed by (samples per bit / 2).
|
||||
// We then lowpass-filter the samples with a
|
||||
// Chebyshev filter. The lowpass filtering serves
|
||||
// to "smooth out" the variations in the samples.
|
||||
|
||||
afsk->iirX[0] = afsk->iirX[1];
|
||||
afsk->iirX[1] = ((int8_t)fifo_pop(&afsk->delayFifo) * currentSample) >> 2;
|
||||
|
||||
afsk->iirY[0] = afsk->iirY[1];
|
||||
|
||||
afsk->iirY[1] = afsk->iirX[0] + afsk->iirX[1] + (afsk->iirY[0] >> 1); // Chebyshev filter
|
||||
|
||||
|
||||
// We put the sampled bit in a delay-line:
|
||||
// First we bitshift everything 1 left
|
||||
afsk->sampledBits <<= 1;
|
||||
// And then add the sampled bit to our delay line
|
||||
afsk->sampledBits |= (afsk->iirY[1] > 0) ? 1 : 0;
|
||||
|
||||
// Put the current raw sample in the delay FIFO
|
||||
fifo_push(&afsk->delayFifo, currentSample);
|
||||
|
||||
// We need to check whether there is a signal transition.
|
||||
// If there is, we can recalibrate the phase of our
|
||||
// sampler to stay in sync with the transmitter. A bit of
|
||||
// explanation is required to understand how this works.
|
||||
// Since we have PHASE_MAX/PHASE_BITS = 8 samples per bit,
|
||||
// we employ a phase counter (currentPhase), that increments
|
||||
// by PHASE_BITS everytime a sample is captured. When this
|
||||
// counter reaches PHASE_MAX, it wraps around by modulus
|
||||
// PHASE_MAX. We then look at the last three samples we
|
||||
// captured and determine if the bit was a one or a zero.
|
||||
//
|
||||
// This gives us a "window" looking into the stream of
|
||||
// samples coming from the ADC. Sort of like this:
|
||||
//
|
||||
// Past Future
|
||||
// 0000000011111111000000001111111100000000
|
||||
// |________|
|
||||
// ||
|
||||
// Window
|
||||
//
|
||||
// Every time we detect a signal transition, we adjust
|
||||
// where this window is positioned little. How much we
|
||||
// adjust it is defined by PHASE_INC. If our current phase
|
||||
// phase counter value is less than half of PHASE_MAX (ie,
|
||||
// the window size) when a signal transition is detected,
|
||||
// add PHASE_INC to our phase counter, effectively moving
|
||||
// the window a little bit backward (to the left in the
|
||||
// illustration), inversely, if the phase counter is greater
|
||||
// than half of PHASE_MAX, we move it forward a little.
|
||||
// This way, our "window" is constantly seeking to position
|
||||
// it's center at the bit transitions. Thus, we synchronise
|
||||
// our timing to the transmitter, even if it's timing is
|
||||
// a little off compared to our own.
|
||||
if (SIGNAL_TRANSITIONED(afsk->sampledBits)) {
|
||||
if (afsk->currentPhase < PHASE_THRESHOLD) {
|
||||
afsk->currentPhase += PHASE_INC;
|
||||
} else {
|
||||
afsk->currentPhase -= PHASE_INC;
|
||||
}
|
||||
}
|
||||
|
||||
// We increment our phase counter
|
||||
afsk->currentPhase += PHASE_BITS;
|
||||
|
||||
// Check if we have reached the end of
|
||||
// our sampling window.
|
||||
if (afsk->currentPhase >= PHASE_MAX) {
|
||||
// If we have, wrap around our phase
|
||||
// counter by modulus
|
||||
afsk->currentPhase %= PHASE_MAX;
|
||||
|
||||
// Bitshift to make room for the next
|
||||
// bit in our stream of demodulated bits
|
||||
afsk->actualBits <<= 1;
|
||||
|
||||
// We determine the actual bit value by reading
|
||||
// the last 3 sampled bits. If there is three or
|
||||
// more 1's, we will assume that the transmitter
|
||||
// sent us a one, otherwise we assume a zero
|
||||
uint8_t bits = afsk->sampledBits & 0x07;
|
||||
if (bits == 0x07 || // 111
|
||||
bits == 0x06 || // 110
|
||||
bits == 0x05 || // 101
|
||||
bits == 0x03 // 011
|
||||
) {
|
||||
afsk->actualBits |= 1;
|
||||
}
|
||||
|
||||
//// Alternative using five bits ////////////////
|
||||
// uint8_t bits = afsk->sampledBits & 0x0f;
|
||||
// uint8_t c = 0;
|
||||
// c += bits & BV(1);
|
||||
// c += bits & BV(2);
|
||||
// c += bits & BV(3);
|
||||
// c += bits & BV(4);
|
||||
// c += bits & BV(5);
|
||||
// if (c >= 3) afsk->actualBits |= 1;
|
||||
/////////////////////////////////////////////////
|
||||
|
||||
// Now we can pass the actual bit to the HDLC parser.
|
||||
// We are using NRZ coding, so if 2 consecutive bits
|
||||
// have the same value, we have a 1, otherwise a 0.
|
||||
// We use the TRANSITION_FOUND function to determine this.
|
||||
//
|
||||
// This is smart in combination with bit stuffing,
|
||||
// since it ensures a transmitter will never send more
|
||||
// than five consecutive 1's. When sending consecutive
|
||||
// ones, the signal stays at the same level, and if
|
||||
// this happens for longer periods of time, we would
|
||||
// not be able to synchronize our phase to the transmitter
|
||||
// and would start experiencing "bit slip".
|
||||
//
|
||||
// By combining bit-stuffing with NRZ coding, we ensure
|
||||
// that the signal will regularly make transitions
|
||||
// that we can use to synchronize our phase.
|
||||
//
|
||||
// We also check the return of the Link Control parser
|
||||
// to check if an error occured.
|
||||
|
||||
if (!hdlcParse(&afsk->hdlc, !TRANSITION_FOUND(afsk->actualBits), &afsk->rxFifo)) {
|
||||
afsk->status |= 1;
|
||||
if (fifo_isfull(&afsk->rxFifo)) {
|
||||
fifo_flush(&afsk->rxFifo);
|
||||
afsk->status = 0;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
|
||||
ISR(ADC_vect) {
|
||||
++_clock;
|
||||
TIFR1 = _BV(ICF1);
|
||||
AFSK_adc_isr(AFSK_modem, ((int16_t)((ADC) >> 2) - 128));
|
||||
if (hw_afsk_dac_isr) {
|
||||
DAC_PORT = (AFSK_dac_isr(AFSK_modem) & 0xF0) | (DAC_PORT & 0x0F);
|
||||
} else {
|
||||
DAC_PORT = 128 | (DAC_PORT & 0x0F);
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,136 @@
|
|||
#ifndef AFSK_H
|
||||
#define AFSK_H
|
||||
|
||||
#include "device.h"
|
||||
#include <stdint.h>
|
||||
#include <stdbool.h>
|
||||
#include <stdio.h>
|
||||
#include <avr/pgmspace.h>
|
||||
#include "util/FIFO.h"
|
||||
#include "util/time.h"
|
||||
#include "protocol/HDLC.h"
|
||||
|
||||
#define SIN_LEN 512
|
||||
static const uint8_t sin_table[] PROGMEM =
|
||||
{
|
||||
128, 129, 131, 132, 134, 135, 137, 138, 140, 142, 143, 145, 146, 148, 149, 151,
|
||||
152, 154, 155, 157, 158, 160, 162, 163, 165, 166, 167, 169, 170, 172, 173, 175,
|
||||
176, 178, 179, 181, 182, 183, 185, 186, 188, 189, 190, 192, 193, 194, 196, 197,
|
||||
198, 200, 201, 202, 203, 205, 206, 207, 208, 210, 211, 212, 213, 214, 215, 217,
|
||||
218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233,
|
||||
234, 234, 235, 236, 237, 238, 238, 239, 240, 241, 241, 242, 243, 243, 244, 245,
|
||||
245, 246, 246, 247, 248, 248, 249, 249, 250, 250, 250, 251, 251, 252, 252, 252,
|
||||
253, 253, 253, 253, 254, 254, 254, 254, 254, 255, 255, 255, 255, 255, 255, 255,
|
||||
};
|
||||
|
||||
inline static uint8_t sinSample(uint16_t i) {
|
||||
uint16_t newI = i % (SIN_LEN/2);
|
||||
newI = (newI >= (SIN_LEN/4)) ? (SIN_LEN/2 - newI -1) : newI;
|
||||
uint8_t sine = pgm_read_byte(&sin_table[newI]);
|
||||
return (i >= (SIN_LEN/2)) ? (255 - sine) : sine;
|
||||
}
|
||||
|
||||
|
||||
#define SWITCH_TONE(inc) (((inc) == MARK_INC) ? SPACE_INC : MARK_INC)
|
||||
#define BITS_DIFFER(bits1, bits2) (((bits1)^(bits2)) & 0x01)
|
||||
#define DUAL_XOR(bits1, bits2) ((((bits1)^(bits2)) & 0x03) == 0x03)
|
||||
#define SIGNAL_TRANSITIONED(bits) DUAL_XOR((bits), (bits) >> 2)
|
||||
#define TRANSITION_FOUND(bits) BITS_DIFFER((bits), (bits) >> 1)
|
||||
|
||||
#define CPU_FREQ F_CPU
|
||||
|
||||
#define CONFIG_AFSK_RX_BUFLEN 64
|
||||
#define CONFIG_AFSK_TX_BUFLEN 64
|
||||
#define CONFIG_AFSK_RXTIMEOUT 0
|
||||
#define CONFIG_AFSK_PREAMBLE_LEN 150UL
|
||||
#define CONFIG_AFSK_TRAILER_LEN 50UL
|
||||
#define SAMPLERATE 9600
|
||||
#define BITRATE 1200
|
||||
#define SAMPLESPERBIT (SAMPLERATE / BITRATE)
|
||||
#define BIT_STUFF_LEN 5
|
||||
#define MARK_FREQ 1200
|
||||
#define SPACE_FREQ 2200
|
||||
#define PHASE_BITS 8 // How much to increment phase counter each sample
|
||||
#define PHASE_INC 1 // Nudge by an eigth of a sample each adjustment
|
||||
#define PHASE_MAX (SAMPLESPERBIT * PHASE_BITS) // Resolution of our phase counter = 64
|
||||
#define PHASE_THRESHOLD (PHASE_MAX / 2) // Target transition point of our phase window
|
||||
|
||||
|
||||
typedef struct Hdlc
|
||||
{
|
||||
uint8_t demodulatedBits;
|
||||
uint8_t bitIndex;
|
||||
uint8_t currentByte;
|
||||
bool receiving;
|
||||
} Hdlc;
|
||||
|
||||
typedef struct Afsk
|
||||
{
|
||||
// Stream access to modem
|
||||
FILE fd;
|
||||
|
||||
// General values
|
||||
Hdlc hdlc; // We need a link control structure
|
||||
uint16_t preambleLength; // Length of sync preamble
|
||||
uint16_t tailLength; // Length of transmission tail
|
||||
|
||||
// Modulation values
|
||||
uint8_t sampleIndex; // Current sample index for outgoing bit
|
||||
uint8_t currentOutputByte; // Current byte to be modulated
|
||||
uint8_t txBit; // Mask of current modulated bit
|
||||
bool bitStuff; // Whether bitstuffing is allowed
|
||||
|
||||
uint8_t bitstuffCount; // Counter for bit-stuffing
|
||||
|
||||
uint16_t phaseAcc; // Phase accumulator
|
||||
uint16_t phaseInc; // Phase increment per sample
|
||||
|
||||
FIFOBuffer txFifo; // FIFO for transmit data
|
||||
uint8_t txBuf[CONFIG_AFSK_TX_BUFLEN]; // Actial data storage for said FIFO
|
||||
|
||||
volatile bool sending; // Set when modem is sending
|
||||
|
||||
// Demodulation values
|
||||
FIFOBuffer delayFifo; // Delayed FIFO for frequency discrimination
|
||||
int8_t delayBuf[SAMPLESPERBIT / 2 + 1]; // Actual data storage for said FIFO
|
||||
|
||||
FIFOBuffer rxFifo; // FIFO for received data
|
||||
uint8_t rxBuf[CONFIG_AFSK_RX_BUFLEN]; // Actual data storage for said FIFO
|
||||
|
||||
int16_t iirX[2]; // IIR Filter X cells
|
||||
int16_t iirY[2]; // IIR Filter Y cells
|
||||
|
||||
uint8_t sampledBits; // Bits sampled by the demodulator (at ADC speed)
|
||||
int8_t currentPhase; // Current phase of the demodulator
|
||||
uint8_t actualBits; // Actual found bits at correct bitrate
|
||||
|
||||
volatile int status; // Status of the modem, 0 means OK
|
||||
|
||||
} Afsk;
|
||||
|
||||
#define DIV_ROUND(dividend, divisor) (((dividend) + (divisor) / 2) / (divisor))
|
||||
#define MARK_INC (uint16_t)(DIV_ROUND(SIN_LEN * (uint32_t)MARK_FREQ, CONFIG_AFSK_DAC_SAMPLERATE))
|
||||
#define SPACE_INC (uint16_t)(DIV_ROUND(SIN_LEN * (uint32_t)SPACE_FREQ, CONFIG_AFSK_DAC_SAMPLERATE))
|
||||
|
||||
#define AFSK_DAC_IRQ_START() do { extern bool hw_afsk_dac_isr; hw_afsk_dac_isr = true; } while (0)
|
||||
#define AFSK_DAC_IRQ_STOP() do { extern bool hw_afsk_dac_isr; hw_afsk_dac_isr = false; } while (0)
|
||||
#define AFSK_DAC_INIT() do { DAC_DDR |= 0xF0; } while (0)
|
||||
|
||||
// Here's some macros for controlling the RX/TX LEDs
|
||||
// THE _INIT() functions writes to the DDRB register
|
||||
// to configure the pins as output pins, and the _ON()
|
||||
// and _OFF() functions writes to the PORT registers
|
||||
// to turn the pins on or off.
|
||||
#define LED_TX_INIT() do { DAC_DDR |= _BV(1); } while (0)
|
||||
#define LED_TX_ON() do { DAC_PORT |= _BV(1); } while (0)
|
||||
#define LED_TX_OFF() do { DAC_PORT &= ~_BV(1); } while (0)
|
||||
|
||||
#define LED_RX_INIT() do { DAC_DDR |= _BV(2); } while (0)
|
||||
#define LED_RX_ON() do { DAC_PORT |= _BV(2); } while (0)
|
||||
#define LED_RX_OFF() do { DAC_PORT &= ~_BV(2); } while (0)
|
||||
|
||||
void AFSK_init(Afsk *afsk);
|
||||
void AFSK_transmit(char *buffer, size_t size);
|
||||
void AFSK_poll(Afsk *afsk);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,47 @@
|
|||
#include "Serial.h"
|
||||
#include <util/setbaud.h>
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
|
||||
void serial_init(Serial *serial) {
|
||||
memset(serial, 0, sizeof(*serial));
|
||||
UBRR0H = UBRRH_VALUE;
|
||||
UBRR0L = UBRRL_VALUE;
|
||||
|
||||
#if USE_2X
|
||||
UCSR0A |= _BV(U2X0);
|
||||
#else
|
||||
UCSR0A &= ~(_BV(U2X0));
|
||||
#endif
|
||||
|
||||
// Set to 8-bit data, enable RX and TX
|
||||
UCSR0C = _BV(UCSZ01) | _BV(UCSZ00);
|
||||
UCSR0B = _BV(RXEN0) | _BV(TXEN0);
|
||||
|
||||
FILE uart0_fd = FDEV_SETUP_STREAM(uart0_putchar, uart0_getchar, _FDEV_SETUP_RW);
|
||||
|
||||
serial->uart0 = uart0_fd;
|
||||
}
|
||||
|
||||
bool serial_available(uint8_t index) {
|
||||
if (index == 0) {
|
||||
if (UCSR0A & _BV(RXC0)) return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
|
||||
void uart0_putchar(char c) {
|
||||
loop_until_bit_is_set(UCSR0A, UDRE0);
|
||||
UDR0 = c;
|
||||
}
|
||||
|
||||
char uart0_getchar(void) {
|
||||
loop_until_bit_is_set(UCSR0A, RXC0);
|
||||
return UDR0;
|
||||
}
|
||||
|
||||
char uart0_getchar_nowait(void) {
|
||||
if (!(UCSR0A & _BV(RXC0))) return EOF;
|
||||
return UDR0;
|
||||
}
|
||||
|
|
@ -0,0 +1,20 @@
|
|||
#ifndef SERIAL_H
|
||||
#define SERIAL_H
|
||||
|
||||
#include "device.h"
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdbool.h>
|
||||
#include <avr/io.h>
|
||||
|
||||
typedef struct Serial {
|
||||
FILE uart0;
|
||||
} Serial;
|
||||
|
||||
void serial_init(Serial *serial);
|
||||
bool serial_available(uint8_t index);
|
||||
void uart0_putchar(char c);
|
||||
char uart0_getchar(void);
|
||||
char uart0_getchar_nowait(void);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,48 @@
|
|||
#include <stdbool.h>
|
||||
#include <avr/io.h>
|
||||
|
||||
#include "device.h"
|
||||
#include "util/FIFO.h"
|
||||
#include "hardware/AFSK.h"
|
||||
#include "hardware/Serial.h"
|
||||
#include "protocol/AX25.h"
|
||||
#include "protocol/KISS.h"
|
||||
|
||||
#define FEND 0xC0
|
||||
#define FESC 0xDB
|
||||
#define TFEND 0xDC
|
||||
#define TFESC 0xDD
|
||||
|
||||
Serial serial;
|
||||
Afsk modem;
|
||||
AX25Ctx AX25;
|
||||
|
||||
static void ax25_callback(struct AX25Ctx *ctx) {
|
||||
kiss_messageCallback(ctx);
|
||||
}
|
||||
|
||||
void init(void) {
|
||||
AFSK_init(&modem);
|
||||
serial_init(&serial);
|
||||
ax25_init(&AX25, &modem.fd, ax25_callback);
|
||||
kiss_init(&AX25, &modem, &serial);
|
||||
|
||||
stdout = &serial.uart0;
|
||||
stdin = &serial.uart0;
|
||||
}
|
||||
|
||||
int main (void) {
|
||||
init();
|
||||
|
||||
while (true) {
|
||||
ax25_poll(&AX25);
|
||||
|
||||
if (serial_available(0)) {
|
||||
char sbyte = uart0_getchar_nowait();
|
||||
kiss_serialCallback(sbyte);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
return(0);
|
||||
}
|
||||
|
|
@ -0,0 +1,77 @@
|
|||
#include <string.h>
|
||||
#include "AX25.h"
|
||||
#include "protocol/HDLC.h"
|
||||
#include "util/CRC-CCIT.h"
|
||||
#include "../hardware/AFSK.h"
|
||||
|
||||
void ax25_init(AX25Ctx *ctx, FILE *channel, ax25_callback_t hook) {
|
||||
memset(ctx, 0, sizeof(*ctx));
|
||||
ctx->ch = channel;
|
||||
ctx->hook = hook;
|
||||
ctx->crc_in = ctx->crc_out = CRC_CCIT_INIT_VAL;
|
||||
}
|
||||
|
||||
static void ax25_decode(AX25Ctx *ctx) {
|
||||
#if SERIAL_PROTOCOL == PROTOCOL_KISS
|
||||
if (ctx->hook) ctx->hook(ctx);
|
||||
#endif
|
||||
}
|
||||
|
||||
void ax25_poll(AX25Ctx *ctx) {
|
||||
int c;
|
||||
|
||||
while ((c = fgetc(ctx->ch)) != EOF) {
|
||||
if (!ctx->escape && c == HDLC_FLAG) {
|
||||
if (ctx->frame_len >= AX25_MIN_FRAME_LEN) {
|
||||
if (ctx->crc_in == AX25_CRC_CORRECT) {
|
||||
ax25_decode(ctx);
|
||||
}
|
||||
}
|
||||
ctx->sync = true;
|
||||
ctx->crc_in = CRC_CCIT_INIT_VAL;
|
||||
ctx->frame_len = 0;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (!ctx->escape && c == HDLC_RESET) {
|
||||
ctx->sync = false;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (!ctx->escape && c == AX25_ESC) {
|
||||
ctx->escape = true;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (ctx->sync) {
|
||||
if (ctx->frame_len < AX25_MAX_FRAME_LEN) {
|
||||
ctx->buf[ctx->frame_len++] = c;
|
||||
ctx->crc_in = update_crc_ccit(c, ctx->crc_in);
|
||||
} else {
|
||||
ctx->sync = false;
|
||||
}
|
||||
}
|
||||
ctx->escape = false;
|
||||
}
|
||||
}
|
||||
|
||||
static void ax25_putchar(AX25Ctx *ctx, uint8_t c)
|
||||
{
|
||||
if (c == HDLC_FLAG || c == HDLC_RESET || c == AX25_ESC) fputc(AX25_ESC, ctx->ch);
|
||||
ctx->crc_out = update_crc_ccit(c, ctx->crc_out);
|
||||
fputc(c, ctx->ch);
|
||||
}
|
||||
|
||||
void ax25_sendRaw(AX25Ctx *ctx, void *_buf, size_t len) {
|
||||
ctx->crc_out = CRC_CCIT_INIT_VAL;
|
||||
fputc(HDLC_FLAG, ctx->ch);
|
||||
const uint8_t *buf = (const uint8_t *)_buf;
|
||||
while (len--) ax25_putchar(ctx, *buf++);
|
||||
|
||||
uint8_t crcl = (ctx->crc_out & 0xff) ^ 0xff;
|
||||
uint8_t crch = (ctx->crc_out >> 8) ^ 0xff;
|
||||
ax25_putchar(ctx, crcl);
|
||||
ax25_putchar(ctx, crch);
|
||||
|
||||
fputc(HDLC_FLAG, ctx->ch);
|
||||
}
|
||||
|
|
@ -0,0 +1,37 @@
|
|||
#ifndef PROTOCOL_AX25_H
|
||||
#define PROTOCOL_AX25_H
|
||||
|
||||
#include <stdio.h>
|
||||
#include <stdbool.h>
|
||||
|
||||
#define AX25_MIN_FRAME_LEN 18
|
||||
#define AX25_MAX_FRAME_LEN 850
|
||||
|
||||
#define AX25_CRC_CORRECT 0xF0B8
|
||||
|
||||
#define AX25_CTRL_UI 0x03
|
||||
#define AX25_PID_NOLAYER3 0xF0
|
||||
|
||||
struct AX25Ctx; // Forward declaration
|
||||
|
||||
#if SERIAL_PROTOCOL == PROTOCOL_KISS
|
||||
typedef void (*ax25_callback_t)(struct AX25Ctx *ctx);
|
||||
#endif
|
||||
|
||||
typedef struct AX25Ctx
|
||||
{
|
||||
uint8_t buf[AX25_MAX_FRAME_LEN];
|
||||
FILE *ch;
|
||||
size_t frame_len;
|
||||
uint16_t crc_in;
|
||||
uint16_t crc_out;
|
||||
ax25_callback_t hook;
|
||||
bool sync;
|
||||
bool escape;
|
||||
} AX25Ctx;
|
||||
|
||||
void ax25_poll(AX25Ctx *ctx);
|
||||
void ax25_sendRaw(AX25Ctx *ctx, void *_buf, size_t len);
|
||||
void ax25_init(AX25Ctx *ctx, FILE *channel, ax25_callback_t hook);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,8 @@
|
|||
#ifndef PROTOCOL_HDLC_H
|
||||
#define PROTOCOL_HDLC_H
|
||||
|
||||
#define HDLC_FLAG 0x7E
|
||||
#define HDLC_RESET 0x7F
|
||||
#define AX25_ESC 0x1B
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,120 @@
|
|||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
|
||||
#include "device.h"
|
||||
#include "KISS.h"
|
||||
|
||||
static uint8_t serialBuffer[AX25_MAX_FRAME_LEN]; // Buffer for holding incoming serial data
|
||||
AX25Ctx *ax25ctx;
|
||||
Afsk *channel;
|
||||
Serial *serial;
|
||||
size_t frame_len;
|
||||
bool IN_FRAME;
|
||||
bool ESCAPE;
|
||||
|
||||
uint8_t command = CMD_UNKNOWN;
|
||||
unsigned long custom_preamble = CONFIG_AFSK_PREAMBLE_LEN;
|
||||
unsigned long custom_tail = CONFIG_AFSK_TRAILER_LEN;
|
||||
|
||||
unsigned long slotTime = 200;
|
||||
uint8_t p = 63;
|
||||
|
||||
void kiss_init(AX25Ctx *ax25, Afsk *afsk, Serial *ser) {
|
||||
ax25ctx = ax25;
|
||||
serial = ser;
|
||||
channel = afsk;
|
||||
}
|
||||
|
||||
void kiss_messageCallback(AX25Ctx *ctx) {
|
||||
fputc(FEND, &serial->uart0);
|
||||
fputc(0x00, &serial->uart0);
|
||||
for (unsigned i = 0; i < ctx->frame_len; i++) {
|
||||
uint8_t b = ctx->buf[i];
|
||||
if (b == FEND) {
|
||||
fputc(FESC, &serial->uart0);
|
||||
fputc(TFEND, &serial->uart0);
|
||||
} else if (b == FESC) {
|
||||
fputc(FESC, &serial->uart0);
|
||||
fputc(TFESC, &serial->uart0);
|
||||
} else {
|
||||
fputc(b, &serial->uart0);
|
||||
}
|
||||
}
|
||||
fputc(FEND, &serial->uart0);
|
||||
}
|
||||
|
||||
void kiss_csma(AX25Ctx *ctx, uint8_t *buf, size_t len) {
|
||||
bool sent = false;
|
||||
while (!sent) {
|
||||
//puts("Waiting in CSMA");
|
||||
if(!channel->hdlc.receiving) {
|
||||
uint8_t tp = rand() & 0xFF;
|
||||
if (tp < p) {
|
||||
ax25_sendRaw(ctx, buf, len);
|
||||
sent = true;
|
||||
} else {
|
||||
ticks_t start = timer_clock();
|
||||
long slot_ticks = ms_to_ticks(slotTime);
|
||||
while (timer_clock() - start < slot_ticks) {
|
||||
cpu_relax();
|
||||
}
|
||||
}
|
||||
} else {
|
||||
while (!sent && channel->hdlc.receiving) {
|
||||
// Continously poll the modem for data
|
||||
// while waiting, so we don't overrun
|
||||
// receive buffers
|
||||
ax25_poll(ax25ctx);
|
||||
|
||||
if (channel->status != 0) {
|
||||
// If an overflow or other error
|
||||
// occurs, we'll back off and drop
|
||||
// this packet silently.
|
||||
channel->status = 0;
|
||||
sent = true;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
void kiss_serialCallback(uint8_t sbyte) {
|
||||
if (IN_FRAME && sbyte == FEND && command == CMD_DATA) {
|
||||
IN_FRAME = false;
|
||||
kiss_csma(ax25ctx, serialBuffer, frame_len);
|
||||
} else if (sbyte == FEND) {
|
||||
IN_FRAME = true;
|
||||
command = CMD_UNKNOWN;
|
||||
frame_len = 0;
|
||||
} else if (IN_FRAME && frame_len < AX25_MAX_FRAME_LEN) {
|
||||
// Have a look at the command byte first
|
||||
if (frame_len == 0 && command == CMD_UNKNOWN) {
|
||||
// MicroModem supports only one HDLC port, so we
|
||||
// strip off the port nibble of the command byte
|
||||
sbyte = sbyte & 0x0F;
|
||||
command = sbyte;
|
||||
} else if (command == CMD_DATA) {
|
||||
if (sbyte == FESC) {
|
||||
ESCAPE = true;
|
||||
} else {
|
||||
if (ESCAPE) {
|
||||
if (sbyte == TFEND) sbyte = FEND;
|
||||
if (sbyte == TFESC) sbyte = FESC;
|
||||
ESCAPE = false;
|
||||
}
|
||||
serialBuffer[frame_len++] = sbyte;
|
||||
}
|
||||
} else if (command == CMD_TXDELAY) {
|
||||
custom_preamble = sbyte * 10UL;
|
||||
} else if (command == CMD_TXTAIL) {
|
||||
custom_tail = sbyte * 10;
|
||||
} else if (command == CMD_SLOTTIME) {
|
||||
slotTime = sbyte * 10;
|
||||
} else if (command == CMD_P) {
|
||||
p = sbyte;
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,29 @@
|
|||
#ifndef _PROTOCOL_KISS
|
||||
#define _PROTOCOL_KISS 0x02
|
||||
|
||||
#include "../hardware/AFSK.h"
|
||||
#include "../hardware/Serial.h"
|
||||
#include "../util/time.h"
|
||||
#include "AX25.h"
|
||||
|
||||
#define FEND 0xC0
|
||||
#define FESC 0xDB
|
||||
#define TFEND 0xDC
|
||||
#define TFESC 0xDD
|
||||
|
||||
#define CMD_UNKNOWN 0xFE
|
||||
#define CMD_DATA 0x00
|
||||
#define CMD_TXDELAY 0x01
|
||||
#define CMD_P 0x02
|
||||
#define CMD_SLOTTIME 0x03
|
||||
#define CMD_TXTAIL 0x04
|
||||
#define CMD_FULLDUPLEX 0x05
|
||||
#define CMD_SETHARDWARE 0x06
|
||||
#define CMD_RETURN 0xFF
|
||||
|
||||
void kiss_init(AX25Ctx *ax25, Afsk *afsk, Serial *ser);
|
||||
void kiss_csma(AX25Ctx *ctx, uint8_t *buf, size_t len);
|
||||
void kiss_messageCallback(AX25Ctx *ctx);
|
||||
void kiss_serialCallback(uint8_t sbyte);
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,36 @@
|
|||
#include "CRC-CCIT.h"
|
||||
|
||||
const uint16_t crc_ccit_table[256] PROGMEM = {
|
||||
0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
|
||||
0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
|
||||
0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
|
||||
0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
|
||||
0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
|
||||
0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
|
||||
0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
|
||||
0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
|
||||
0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
|
||||
0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
|
||||
0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
|
||||
0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
|
||||
0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
|
||||
0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
|
||||
0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
|
||||
0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
|
||||
0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
|
||||
0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
|
||||
0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
|
||||
0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
|
||||
0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
|
||||
0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
|
||||
0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
|
||||
0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
|
||||
0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
|
||||
0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
|
||||
0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
|
||||
0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
|
||||
0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
|
||||
0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
|
||||
0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
|
||||
0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78,
|
||||
};
|
||||
|
|
@ -0,0 +1,18 @@
|
|||
// CRC-CCIT Implementation based on work by Francesco Sacchi
|
||||
|
||||
#ifndef CRC_CCIT_H
|
||||
#define CRC_CCIT_H
|
||||
|
||||
#include <stdint.h>
|
||||
#include <avr/pgmspace.h>
|
||||
|
||||
#define CRC_CCIT_INIT_VAL ((uint16_t)0xFFFF)
|
||||
|
||||
extern const uint16_t crc_ccit_table[256];
|
||||
|
||||
inline uint16_t update_crc_ccit(uint8_t c, uint16_t prev_crc) {
|
||||
return (prev_crc >> 8) ^ pgm_read_word(&crc_ccit_table[(prev_crc ^ c) & 0xff]);
|
||||
}
|
||||
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,85 @@
|
|||
#ifndef UTIL_FIFO_H
|
||||
#define UTIL_FIFO_H
|
||||
|
||||
#include <stddef.h>
|
||||
#include <util/atomic.h>
|
||||
|
||||
typedef struct FIFOBuffer
|
||||
{
|
||||
unsigned char *begin;
|
||||
unsigned char *end;
|
||||
unsigned char * volatile head;
|
||||
unsigned char * volatile tail;
|
||||
} FIFOBuffer;
|
||||
|
||||
inline bool fifo_isempty(const FIFOBuffer *f) {
|
||||
return f->head == f->tail;
|
||||
}
|
||||
|
||||
inline bool fifo_isfull(const FIFOBuffer *f) {
|
||||
return ((f->head == f->begin) && (f->tail == f->end)) || (f->tail == f->head - 1);
|
||||
}
|
||||
|
||||
inline void fifo_push(FIFOBuffer *f, unsigned char c) {
|
||||
*(f->tail) = c;
|
||||
|
||||
if (f->tail == f->end) {
|
||||
f->tail = f->begin;
|
||||
} else {
|
||||
f->tail++;
|
||||
}
|
||||
}
|
||||
|
||||
inline unsigned char fifo_pop(FIFOBuffer *f) {
|
||||
if(f->head == f->end) {
|
||||
f->head = f->begin;
|
||||
return *(f->end);
|
||||
} else {
|
||||
return *(f->head++);
|
||||
}
|
||||
}
|
||||
|
||||
inline void fifo_flush(FIFOBuffer *f) {
|
||||
f->head = f->tail;
|
||||
}
|
||||
|
||||
inline bool fifo_isempty_locked(const FIFOBuffer *f) {
|
||||
bool result;
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
result = fifo_isempty(f);
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
inline bool fifo_isfull_locked(const FIFOBuffer *f) {
|
||||
bool result;
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
result = fifo_isfull(f);
|
||||
}
|
||||
return result;
|
||||
}
|
||||
|
||||
inline void fifo_push_locked(FIFOBuffer *f, unsigned char c) {
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
fifo_push(f, c);
|
||||
}
|
||||
}
|
||||
|
||||
inline unsigned char fifo_pop_locked(FIFOBuffer *f) {
|
||||
unsigned char c;
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
c = fifo_pop(f);
|
||||
}
|
||||
return c;
|
||||
}
|
||||
|
||||
inline void fifo_init(FIFOBuffer *f, unsigned char *buffer, size_t size) {
|
||||
f->head = f->tail = f->begin = buffer;
|
||||
f->end = buffer + size -1;
|
||||
}
|
||||
|
||||
inline size_t fifo_len(FIFOBuffer *f) {
|
||||
return f->end - f->begin;
|
||||
}
|
||||
|
||||
#endif
|
||||
|
|
@ -0,0 +1,34 @@
|
|||
#ifndef UTIL_TIME_H
|
||||
#define UTIL_TIME_H
|
||||
|
||||
#include "device.h"
|
||||
|
||||
#define DIV_ROUND(dividend, divisor) (((dividend) + (divisor) / 2) / (divisor))
|
||||
#define CLOCK_TICKS_PER_SEC CONFIG_AFSK_DAC_SAMPLERATE
|
||||
|
||||
typedef int32_t ticks_t;
|
||||
typedef int32_t mtime_t;
|
||||
|
||||
volatile ticks_t _clock;
|
||||
|
||||
inline ticks_t timer_clock(void) {
|
||||
ticks_t result;
|
||||
|
||||
ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
|
||||
result = _clock;
|
||||
}
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
|
||||
inline ticks_t ms_to_ticks(mtime_t ms) {
|
||||
return ms * DIV_ROUND(CLOCK_TICKS_PER_SEC, 1000);
|
||||
}
|
||||
|
||||
inline void cpu_relax(void) {
|
||||
// Do nothing!
|
||||
}
|
||||
|
||||
|
||||
#endif
|
||||
Loading…
Reference in New Issue