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Work on sample rate independency

This commit is contained in:
Mark Qvist 2018-12-29 16:06:48 +01:00
parent f285ae8cc0
commit d515be49ff
1 changed files with 5 additions and 3 deletions
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8
hardware/AFSK.h
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@ -33,9 +33,11 @@ inline static uint8_t sinSample(uint16_t i) {
#define SWITCH_TONE(inc) (((inc) == MARK_INC) ? SPACE_INC : MARK_INC)
#define BITS_DIFFER(bits1, bits2) (((bits1)^(bits2)) & 0x01)
#define TRANSITION_FOUND(bits) BITS_DIFFER((bits), (bits) >> 1)
// TODO: Maybe expand number of bits looked at here:
#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
@ -55,7 +57,7 @@ inline static uint8_t sinSample(uint16_t i) {
#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_MAX (SAMPLESPERBIT * PHASE_BITS) // Resolution of our phase counter
#define PHASE_THRESHOLD (PHASE_MAX / 2) // Target transition point of our phase window
#define DCD_TIMEOUT_SAMPLES CONFIG_SAMPLERATE/100
@ -118,7 +120,7 @@ typedef struct Afsk
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)
uint16_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