/*------------------------------------------------------------------ * * Module: audio.h * * Purpose: Interface to audio device commonly called a "sound card" * for historical reasons. * *---------------------------------------------------------------*/ #ifndef AUDIO_H #define AUDIO_H 1 #include "direwolf.h" /* for MAX_CHANS used throughout the application. */ #include "ax25_pad.h" /* for AX25_MAX_ADDR_LEN */ /* * PTT control. */ enum ptt_method_e { PTT_METHOD_NONE, /* VOX or no transmit. */ PTT_METHOD_SERIAL, /* Serial port RTS or DTR. */ PTT_METHOD_GPIO, /* General purpose I/O, Linux only. */ PTT_METHOD_LPT }; /* Parallel printer port, Linux only. */ typedef enum ptt_method_e ptt_method_t; enum ptt_line_e { PTT_LINE_NONE = 0, PTT_LINE_RTS = 1, PTT_LINE_DTR = 2 }; // Important: 0 for neither. typedef enum ptt_line_e ptt_line_t; enum audio_in_type_e { AUDIO_IN_TYPE_SOUNDCARD, AUDIO_IN_TYPE_SDR_UDP, AUDIO_IN_TYPE_STDIN }; /* For option to try fixing frames with bad CRC. */ typedef enum retry_e { RETRY_NONE=0, RETRY_SWAP_SINGLE=1, RETRY_SWAP_DOUBLE=2, RETRY_SWAP_TRIPLE=3, RETRY_REMOVE_SINGLE=4, RETRY_REMOVE_DOUBLE=5, RETRY_REMOVE_TRIPLE=6, RETRY_INSERT_SINGLE=7, RETRY_INSERT_DOUBLE=8, RETRY_SWAP_TWO_SEP=9, RETRY_SWAP_MANY=10, RETRY_REMOVE_MANY=11, RETRY_REMOVE_TWO_SEP=12, RETRY_MAX = 13} retry_t; typedef enum sanity_e { SANITY_APRS, SANITY_AX25, SANITY_NONE } sanity_t; struct audio_s { /* Previously we could handle only a single audio device. */ /* In version 1.2, we generalize this to handle multiple devices. */ /* This means we can now have more than 2 radio channels. */ struct adev_param_s { /* Properites of the sound device. */ int defined; /* Was device defined? */ /* First one defaults to yes. */ char adevice_in[80]; /* Name of the audio input device (or file?). */ /* TODO: Can be "-" to read from stdin. */ char adevice_out[80]; /* Name of the audio output device (or file?). */ int num_channels; /* Should be 1 for mono or 2 for stereo. */ int samples_per_sec; /* Audio sampling rate. Typically 11025, 22050, or 44100. */ int bits_per_sample; /* 8 (unsigned char) or 16 (signed short). */ } adev[MAX_ADEVS]; /* Common to all channels. */ char tts_script[80]; /* Script for text to speech. */ int statistics_interval; /* Number of seconds between the audio */ /* statistics reports. This is set by */ /* the "-a" option. 0 to disable feature. */ /* Properties for each audio channel, common to receive and transmit. */ /* Can be different for each radio channel. */ struct achan_param_s { int valid; /* Is this channel valid? */ char mycall[AX25_MAX_ADDR_LEN]; /* Call associated with this radio channel. */ /* Could all be the same or different. */ enum modem_t { MODEM_AFSK, MODEM_BASEBAND, MODEM_SCRAMBLE, MODEM_OFF } modem_type; /* Usual AFSK. */ /* Baseband signal. Not used yet. */ /* Scrambled http://www.amsat.org/amsat/articles/g3ruh/109/fig03.gif */ /* No modem. Might want this for DTMF only channel. */ enum dtmf_decode_t { DTMF_DECODE_OFF, DTMF_DECODE_ON } dtmf_decode; /* Originally the DTMF ("Touch Tone") decoder was always */ /* enabled because it took a negligible amount of CPU. */ /* There were complaints about the false positives when */ /* hearing other modulation schemes on HF SSB so now it */ /* is enabled only when needed. */ /* "On" will send special "t" packet to attached applications */ /* and process as APRStt. Someday we might want to separate */ /* these but for now, we have a single off/on. */ int decimate; /* Reduce AFSK sample rate by this factor to */ /* decrease computational requirements. */ int mark_freq; /* Two tones for AFSK modulation, in Hz. */ int space_freq; /* Standard tones are 1200 and 2200 for 1200 baud. */ int baud; /* Data bits (more accurately, symbols) per second. */ /* Standard rates are 1200 for VHF and 300 for HF. */ /* Next 3 come from config file or command line. */ char profiles[16]; /* zero or more of ABC etc, optional + */ int num_freq; /* Number of different frequency pairs for decoders. */ int offset; /* Spacing between filter frequencies. */ /* Next two are derived from 3 above by demod_init. */ int num_demod; /* Number of different demodulators (filters). */ /* Previously this was same as num_subchan but we add */ /* a new variation in version 1.2 where a single modem */ /* can feed multiple slicers and HDLC decoders. */ /* num_slicers could be added to be more general but */ /* for the intial experiment, we can just examine profiles. */ int num_subchan; /* Total number of modems / hdlc decoders for each channel. */ /* Potentially it could be product of strlen(profiles) * num_freq. */ /* Currently can't use both at once. */ /* These are for dealing with imperfect frames. */ enum retry_e fix_bits; /* Level of effort to recover from */ /* a bad FCS on the frame. */ /* 0 = no effort */ /* 1 = try fixing a single bit */ /* 2... = more techniques... */ enum sanity_e sanity_test; /* Sanity test to apply when finding a good */ /* CRC after making a change. */ /* Must look like APRS, AX.25, or anything. */ int passall; /* Allow thru even with bad CRC. */ /* Additional properties for transmit. */ /* Originally we had control outputs only for PTT. */ /* In version 1.2, we generalize this to allow others such as DCD. */ /* Index following structure by one of these: */ #define OCTYPE_PTT 0 #define OCTYPE_DCD 1 #define OCTYPE_FUTURE 2 #define NUM_OCTYPES 3 /* number of values above */ struct { ptt_method_t ptt_method; /* none, serial port, GPIO, LPT. */ char ptt_device[20]; /* Serial device name for PTT. e.g. COM1 or /dev/ttyS0 */ ptt_line_t ptt_line; /* Control line when using serial port. PTT_LINE_RTS, PTT_LINE_DTR. */ ptt_line_t ptt_line2; /* Optional second one: PTT_LINE_NONE when not used. */ int ptt_gpio; /* GPIO number. */ int ptt_lpt_bit; /* Bit number for parallel printer port. */ /* Bit 0 = pin 2, ..., bit 7 = pin 9. */ int ptt_invert; /* Invert the output. */ int ptt_invert2; /* Invert the secondary output. */ } octrl[NUM_OCTYPES]; #define ICTYPE_TXINH 0 #define NUM_ICTYPES 1 struct { int enable; /* should we bother checking this input? */ int gpio; /* GPIO number */ int invert; /* 1 = active low */ } ictrl[NUM_ICTYPES]; /* Transmit timing. */ int dwait; /* First wait extra time for receiver squelch. */ /* Default 0 units of 10 mS each . */ int slottime; /* Slot time in 10 mS units for persistance algorithm. */ /* Typical value is 10 meaning 100 milliseconds. */ int persist; /* Sets probability for transmitting after each */ /* slot time delay. Transmit if a random number */ /* in range of 0 - 255 <= persist value. */ /* Otherwise wait another slot time and try again. */ /* Default value is 63 for 25% probability. */ int txdelay; /* After turning on the transmitter, */ /* send "flags" for txdelay * 10 mS. */ /* Default value is 30 meaning 300 milliseconds. */ int txtail; /* Amount of time to keep transmitting after we */ /* are done sending the data. This is to avoid */ /* dropping PTT too soon and chopping off the end */ /* of the frame. Again 10 mS units. */ /* At this point, I'm thinking of 10 as the default. */ } achan[MAX_CHANS]; }; #if __WIN32__ || __APPLE__ #define DEFAULT_ADEVICE "" /* Windows: Empty string = default audio device. */ #else #if USE_ALSA #define DEFAULT_ADEVICE "default" /* Use default device for ALSA. */ #else #define DEFAULT_ADEVICE "/dev/dsp" /* First audio device for OSS. */ #endif #endif /* * UDP audio receiving port. Couldn't find any standard or usage precedent. * Got the number from this example: http://gqrx.dk/doc/streaming-audio-over-udp * Any better suggestions? */ #define DEFAULT_UDP_AUDIO_PORT 7355 // Maximum size of the UDP buffer (for allowing IP routing, udp packets are often limited to 1472 bytes) #define SDR_UDP_BUF_MAXLEN 2000 #define DEFAULT_NUM_CHANNELS 1 #define DEFAULT_SAMPLES_PER_SEC 44100 /* Very early observations. Might no longer be valid. */ /* 22050 works a lot better than 11025. */ /* 44100 works a little better than 22050. */ /* If you have a reasonable machine, use the highest rate. */ #define MIN_SAMPLES_PER_SEC 8000 #define MAX_SAMPLES_PER_SEC 48000 /* Formerly 44100. */ /* Software defined radio often uses 48000. */ #define DEFAULT_BITS_PER_SAMPLE 16 #define DEFAULT_FIX_BITS RETRY_SWAP_SINGLE /* * Standard for AFSK on VHF FM. * Reversing mark and space makes no difference because * NRZI encoding only cares about change or lack of change * between the two tones. * * HF SSB uses 300 baud and 200 Hz shift. * 1600 & 1800 Hz is a popular tone pair, sometimes * called the KAM tones. */ #define DEFAULT_MARK_FREQ 1200 #define DEFAULT_SPACE_FREQ 2200 #define DEFAULT_BAUD 1200 /* * Typical transmit timings for VHF. */ #define DEFAULT_DWAIT 0 #define DEFAULT_SLOTTIME 10 #define DEFAULT_PERSIST 63 #define DEFAULT_TXDELAY 30 #define DEFAULT_TXTAIL 10 /* * Note that we have two versions of these in audio.c and audio_win.c. * Use one or the other depending on the platform. */ int audio_open (struct audio_s *pa); int audio_get (int a); /* a = audio device, 0 for first */ int audio_put (int a, int c); int audio_flush (int a); void audio_wait (int a); int audio_close (void); #endif /* ifdef AUDIO_H */ /* end audio.h */