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Work on sample rate independency

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Mark Qvist 2018-12-29 15:57:49 +01:00
parent 3fb4c30604
commit f285ae8cc0
4 changed files with 30 additions and 30 deletions
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42
hardware/AFSK.h
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@ -39,8 +39,8 @@ inline static uint8_t sinSample(uint16_t i) {
#define CPU_FREQ F_CPU
#define CONFIG_AFSK_RX_BUFLEN 64
#define CONFIG_AFSK_TX_BUFLEN 64
#define CONFIG_AFSK_RX_BUFLEN CONFIG_SAMPLERATE/150
#define CONFIG_AFSK_TX_BUFLEN CONFIG_SAMPLERATE/150
#define CONFIG_AFSK_RXTIMEOUT 0
#define CONFIG_AFSK_TXWAIT 0UL
#define CONFIG_AFSK_PREAMBLE_LEN 350UL
@ -50,33 +50,25 @@ inline static uint8_t sinSample(uint16_t i) {
#define BITRATE 1200
#define SAMPLESPERBIT (CONFIG_SAMPLERATE / BITRATE)
#define TICKS_BETWEEN_SAMPLES ((((CPU_FREQ+FREQUENCY_CORRECTION)) / CONFIG_SAMPLERATE) - 1)
#define PHASE_INC 1 // Nudge by an eigth of a sample each adjustment
#define DCD_MIN_COUNT 6
#define DCD_TIMEOUT_SAMPLES 96
#if BITRATE == 960
#define FILTER_CUTOFF 600
#define MARK_FREQ 960
#define SPACE_FREQ 1600
#define PHASE_BITS 10 // How much to increment phase counter each sample
#elif BITRATE == 1200
#define FILTER_CUTOFF 600
#define MARK_FREQ 1200
#define SPACE_FREQ 2200
#define PHASE_BITS 8
#elif BITRATE == 1600
#define FILTER_CUTOFF 800
#define MARK_FREQ 1600
#define SPACE_FREQ 2600
#define PHASE_BITS 8
#else
#error Unsupported bitrate!
#endif
// TODO: Calculate based on sample rate
#define PHASE_INC SAMPLESPERBIT/8 // Nudge by an eigth of a sample each adjustment
#define PHASE_BITS 8 // How much to increment phase counter each sample
#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
#define DCD_TIMEOUT_SAMPLES CONFIG_SAMPLERATE/100
#define DCD_MIN_COUNT CONFIG_SAMPLERATE/1600
#if BITRATE == 1200
#define FILTER_CUTOFF 600
#define MARK_FREQ 1200
#define SPACE_FREQ 2200
#else
#error Unsupported bitrate!
#endif
typedef struct Hdlc
{
uint8_t demodulatedBits;
@ -146,7 +138,7 @@ typedef struct Afsk
#define AFSK_DAC_INIT() do { DAC_DDR |= 0xFF; } while (0)
// Here's some macros for controlling the RX/TX LEDs
// THE _INIT() functions writes to the DDRB register
// THE _INIT() functions writes to the DDR registers
// 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.