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gpsctl.c
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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* G P S C T L
* (GPS control)
*
* A utility for querying, configuring, and using a U-Blox GPS on Linux.
*
* This program was tested ONLY on a Raspberry Pi 3B, running Jessie, with a Uputronics board that uses a
* U-Blox M8 GPS module.
*
* Created: October 18, 2017
* Author: Tom Dilatush <[email protected]>
* Github:
* License: MIT
*
* Copyright 2017 Tom Dilatush
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
* documentation files (the "Software"), to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
* to permit persons to whom the Software is furnished to do so.
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of
* the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
* THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE A
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
// TODO: make sure we free any allocated slBuffers!
// TODO: add needed printfs for verbose mode...
// TODO: troll all headers, inserting parameter names and return value comments
// these defines allow compiling on both an OS X development machine and the target Raspberry Pi. If different
// development environments or target machines are needed, these will likely need to be tweaked.
#define _XOPEN_SOURCE 700
#define _DARWIN_C_SOURCE
#define _POSIX_C_SOURCE 199309L
#define _GNU_SOURCE
#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <getopt.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <wiringPi.h>
#include <math.h>
#include "sl_return.h"
#include "sl_options.h"
#include "sl_general.h"
#include "sl_serial.h"
#include "ublox.h"
#include "cJSON.h"
typedef enum { fixQuery, versionQuery, configQuery, satelliteQuery } queryType;
typedef enum { syncNone, syncASCII, syncNMEA, syncUBX } syncType;
typedef struct { char* name; syncType type; } syncTypeRec;
static syncTypeRec syncTypeRecs[] = {
{ "ascii", syncASCII },
{ "nmea", syncNMEA },
{ "ubx", syncUBX }
};
struct clientData_slOptions {
int verbosity;
syncType syncMethod;
const char *port;
int baud;
int minBaud;
int newbaud;
bool report;
bool echo;
bool nmea;
bool json;
int echoSeconds;
queryType queryType;
bool error;
int fdPort;
bool ubxSynchronized;
};
// Set the sync method to that specified in the argument. Returns Ok if there's no argument (and do nothing) or the
// argument was recognized; or an Error if there was an unrecognizable argument.
static slReturn setSyncMethod( const char* arg, clientData_slOptions* clientData ) {
// if no argument was supplied, don't do anything at all...
if( arg == NULL ) return makeOkReturn();
// otherwise, try to match the argument...
for (int i = 0; i < ARRAY_SIZE(syncTypeRecs); i++) {
if (0 == strncmp(arg, syncTypeRecs[i].name, strlen(arg))) {
clientData->syncMethod = syncTypeRecs[i].type;
return makeOkReturn();
}
}
// if we get here, we couldn't find the method, so do nothing but return a problem...
return makeErrorFmtMsgReturn( ERR_ROOT, "\"%s\" is not a recognized synchronization method", arg );
}
// NMEA baud rate synchronizer. This looks for a complete, valid NMEA sentence and then declares victory.
// Returns Ok with true if synchronized, false if timed out.
static slReturn nmeaBaudRateSynchronizer( int fdPort, int maxTimeMs, int verbosity ) {
bool inLine = false;
char last[3];
int cksm = 0;
long long start = currentTimeMs();
// flush any junk we might have in the receiver buffer...
slReturn frResp = flushRx( fdPort );
if( isErrorReturn( frResp ) )
makeErrorMsgReturn( ERR_CAUSE( frResp ), "could not flush receiver prior to synchronization" );
// read characters until either we appear to be synchronized or we run out of time...
while( currentTimeMs() < start + maxTimeMs ) {
slReturn rscResp = readSerialChar( fdPort, start + maxTimeMs - currentTimeMs() );
if( isErrorReturn( rscResp ) )
return makeErrorMsgReturn( ERR_CAUSE( rscResp ), "problem reading a character while synchronizing" );
if( isWarningReturn( rscResp ) )
return makeOkInfoReturn( bool2info( false ) );
char c = getReturnInfoChar( rscResp );
if( inLine ) {
if( (c == '\r') || (c == '\n') ) {
if( last[0] == '*') {
int un = hex2int( last[1] );
if( un >= 0 ) {
int ln = hex2int( last[2] );
if( ln >= 0 ) {
int ck = (un << 4) | ln;
// correct checksum for the last three characters received...
cksm ^= last[0];
cksm ^= last[1];
cksm ^= last[2];
if( ck == cksm ) {
return makeOkInfoReturn( bool2info( true ) );
}
}
}
}
inLine = false;
}
else {
cksm ^= c;
last[0] = last[1];
last[1] = last[2];
last[2] = c;
}
}
else if( c == '$' ) {
inLine = true;
cksm = 0;
}
}
return makeOkInfoReturn( bool2info( false ) );
}
// Attempt to synchronize, using the given method at the current host baud rate. On an Ok response, returns true
// or false for synchronization success as a bool in additional info.
static slReturn syncSerial( const syncType type, clientData_slOptions* clientData ) {
// we're going to allow 250 character times, or 1.5 seconds, whichever is greater...
speedInfo si;
slReturn gsiResp = getSpeedInfo( clientData->fdPort, &si );
if( isErrorReturn( gsiResp ) )
return makeErrorMsgReturn( ERR_CAUSE( gsiResp ), "problem getting speed information" );
int maxMs = (int) max_ll( 1500, si.nsChar * 250 / 1000000 );
switch( type ) {
case syncNMEA: return nmeaBaudRateSynchronizer( clientData->fdPort, maxMs, clientData->verbosity );
case syncASCII: return asciiBaudRateSynchronizer( clientData->fdPort, maxMs, clientData->verbosity );
case syncUBX:
if( clientData->ubxSynchronized ) return makeOkInfoReturn( bool2info( true ) );
slReturn ubsxResp = ubxSynchronizer( clientData->fdPort, maxMs, clientData->verbosity );
if( isErrorReturn( ubsxResp ) ) return ubsxResp;
if( getReturnInfoBool( ubsxResp ) ) clientData->ubxSynchronized = true;
return ubsxResp;
default: return makeErrorFmtMsgReturn( ERR_ROOT, "unknown synchronization type: %d", type );
}
}
// Outputs a fix query, in English or JSON.
static slReturn doFixQuery( const clientData_slOptions* clientData ) {
ubxFix fix = {0}; // zeroes all elements...
slReturn result = ubxGetFix( clientData->fdPort, clientData->verbosity, &fix );
double msl_height_feet = 0.00328084 * fix.height_above_sea_level_mm;
double height_accuracy_feet = 0.00328084 * fix.height_accuracy_mm;
double horizontal_accuracy_feet = 0.00328084 * fix.horizontal_accuracy_mm;
double speed_mph = fix.ground_speed_mm_s * 0.00223694;
double speed_accuracy_mph = fix.ground_speed_accuracy_mm_s * 0.00223694;
if( isErrorReturn( result ) )
return makeErrorMsgReturn( ERR_CAUSE( result ), "Problem obtaining fix from GPS" );
if( clientData->json ) {
cJSON* root = cJSON_CreateObject();
cJSON* objFix = cJSON_CreateObject();
cJSON* time = cJSON_CreateObject();
cJSON_AddItemToObject( root, "fix", objFix );
cJSON_AddNumberToObject( objFix, "latitude_deg", fix.latitude_deg );
cJSON_AddNumberToObject( objFix, "longitude_deg", fix.longitude_deg );
cJSON_AddNumberToObject( objFix, "height_above_ellipsoid_mm", fix.height_above_ellipsoid_mm );
cJSON_AddNumberToObject( objFix, "height_above_mean_sea_level_mm", fix.height_above_sea_level_mm );
cJSON_AddNumberToObject( objFix, "horizontal_accuracy_mm", fix.horizontal_accuracy_mm );
cJSON_AddNumberToObject( objFix, "height_accuracy_mm", fix.height_accuracy_mm );
cJSON_AddNumberToObject( objFix, "ground_speed_mm_sec", fix.ground_speed_mm_s );
cJSON_AddNumberToObject( objFix, "ground_speed_accuracy_mm_sec", fix.ground_speed_accuracy_mm_s );
cJSON_AddNumberToObject( objFix, "heading_deg", fix.heading_deg );
cJSON_AddNumberToObject( objFix, "heading_accuracy_deg", fix.heading_accuracy_deg );
cJSON_AddBoolToObject( objFix, "valid", fix.fix_valid );
cJSON_AddBoolToObject( objFix, "3d", fix.fix_is_3d );
cJSON_AddNumberToObject( root, "number_of_satellites_used", fix.number_of_satellites_used );
cJSON_AddItemToObject( root, "time", time );
cJSON_AddNumberToObject( time, "month", fix.month );
cJSON_AddNumberToObject( time, "day", fix.day );
cJSON_AddNumberToObject( time, "year", fix.year );
cJSON_AddNumberToObject( time, "hour", fix.hour );
cJSON_AddNumberToObject( time, "minute", fix.minute );
cJSON_AddNumberToObject( time, "second", fix.second );
cJSON_AddNumberToObject( time, "accuracy_ns", fix.time_accuracy_ns );
cJSON_AddBoolToObject( time, "valid", fix.time_valid );
cJSON_AddBoolToObject( time, "resolved", fix.time_resolved );
char *jsonStr = cJSON_PrintUnformatted( root );
printf( "%s\n", jsonStr );
cJSON_Delete( root );
}
else {
if( fix.time_resolved && fix.time_valid && fix.date_valid )
printf( " Time (UTC): %02d/%02d/%04d %02d:%02d:%02.0f (mm/dd/yyyy hh:mm:ss)\n",
fix.month, fix.day, fix.year, fix.hour, fix.minute, fix.second );
else
printf( " Time (UTC): not resolved or not valid\n" );
if( fix.fix_valid ) {
printf( " Latitude: %12.8f %c\n", fabs(fix.latitude_deg), (fix.latitude_deg < 0) ? 'S' : 'N');
printf( " Longitude: %12.8f %c\n", fabs(fix.longitude_deg), (fix.longitude_deg < 0) ? 'W' : 'E');
if( fix.fix_is_3d )
printf( " Altitude: %.3f feet\n", msl_height_feet);
else
printf( " Altitude: unknown\n" );
printf( " Motion: %.3f mph at %.3f degrees heading\n", speed_mph, fix.heading_deg);
}
else
printf( " Fix: invalid\n" );
printf( " Satellites: %d used for computing this fix\n", fix.number_of_satellites_used );
printf( " Accuracy: time (%d ns), height (+/-%.3f feet), position (+/-%.3f feet), heading(+/-%.3f degrees), speed(+/-%.3f mph)\n",
fix.time_accuracy_ns, height_accuracy_feet, horizontal_accuracy_feet, fix.heading_accuracy_deg, speed_accuracy_mph );
}
return makeOkReturn();
}
// Outputs a version query, in English or JSON.
static slReturn doVersionQuery( const clientData_slOptions* clientData ) {
ubxVersion version = {0}; // zeroes all elements...
slReturn result = ubxGetVersion( clientData->fdPort, clientData->verbosity, &version );
if( isErrorReturn( result ) )
return makeErrorMsgReturn(ERR_CAUSE( result ), "Problem obtaining version information from GPS" );
if( clientData->json ) {
cJSON *root = cJSON_CreateObject();
cJSON_AddItemToObject( root, "software_version", cJSON_CreateString( version.software ) );
cJSON_AddItemToObject( root, "hardware_version", cJSON_CreateString( version.hardware ) );
cJSON_AddItemToObject( root, "extensions",
cJSON_CreateStringArray( (const char**) version.extensions, version.number_of_extensions ) );
char *jsonStr = cJSON_PrintUnformatted( root );
printf( "%s\n", jsonStr );
cJSON_Delete( root );
}
else {
printf( "Software version: %s\n", version.software );
free( version.software );
printf( "Hardware version: %s\n", version.hardware );
free( version.hardware );
char **ptr = version.extensions;
while( (*ptr) != NULL ) {
printf( " Extension: %s\n", *ptr );
free( (*ptr) );
ptr++;
}
}
return makeOkReturn();
}
// comparison function for satellite search...
int cmpSatellite( const void* a, const void* b ) {
ubxSatellite* c = (ubxSatellite*) a;
ubxSatellite* d = (ubxSatellite*) b;
if( c->used && !d->used ) return -1;
if( d->used && !c->used ) return 1;
return d->cno - c->cno;
}
// Outputs a satellite query, in English or JSON.
static slReturn doSatelliteQuery( const clientData_slOptions* clientData ) {
// get the satellite data from the GPS...
ubxSatellites satellites = {0}; // zeroes all elements...
slReturn ugsResp = ubxGetSatellites( clientData->fdPort, clientData->verbosity, &satellites );
if( isErrorReturn( ugsResp ) )
return makeErrorMsgReturn( ERR_CAUSE( ugsResp ), "Problem obtaining satellites information from GPS" );
// sort the result by used or not, then in descending order of CNo...
qsort( satellites.satellites, (unsigned) satellites.numberOfSatellites, sizeof( ubxSatellite ), cmpSatellite );
if( clientData->json ) {
cJSON* root = cJSON_CreateObject();
cJSON* sats = cJSON_CreateArray();
cJSON_AddNumberToObject( root, "number_of_satellites", satellites.numberOfSatellites );
cJSON_AddItemToObject( root, "satellites", sats );
for( int i = 0; i < satellites.numberOfSatellites; i++ ) {
ubxSatellite* s = satellites.satellites + i;
cJSON* sat = cJSON_CreateObject();
cJSON_AddItemToArray( sats, sat );
cJSON_AddStringToObject( sat, "gnssID", getGnssName( s->gnssID ) );
cJSON_AddNumberToObject( sat, "satelliteID", s->satelliteID );
cJSON_AddNumberToObject( sat, "CNo", s->cno );
cJSON_AddNumberToObject( sat, "elevation", s->elevation );
cJSON_AddNumberToObject( sat, "azimuth", s->azimuth );
cJSON_AddNumberToObject( sat, "pseudoRangeResidual_meters", s->pseudoRangeResidualM );
cJSON_AddStringToObject( sat, "signalQuality", getSignalQuality( s->signalQuality ) );
cJSON_AddBoolToObject( sat, "used", s->used );
cJSON_AddStringToObject( sat, "satelliteHealth", getSatelliteHealth( s->health ) );
cJSON_AddBoolToObject( sat, "diffCorr", s->diffCorr );
cJSON_AddBoolToObject( sat, "smoothed", s->smoothed );
cJSON_AddStringToObject( sat, "orbitSource", getOrbitSource( s->orbitSource ) );
cJSON_AddBoolToObject( sat, "haveEphemeris", s->haveEphemeris );
cJSON_AddBoolToObject( sat, "haveAlmanac", s->haveAlmanac );
cJSON_AddBoolToObject( sat, "haveAssistNowOff", s->haveAssistNowOff );
cJSON_AddBoolToObject( sat, "haveAssistNowAuto", s->haveAssistNowAuto );
cJSON_AddBoolToObject( sat, "sbasCorrUsed", s->sbasCorrUsed );
cJSON_AddBoolToObject( sat, "rtcmCorrUsed", s->rtcmCorrUsed );
cJSON_AddBoolToObject( sat, "prCorrUsed", s->prCorrUsed );
cJSON_AddBoolToObject( sat, "crCorrUsed", s->crCorrUsed );
cJSON_AddBoolToObject( sat, "doCorrUsed", s->doCorrUsed );
}
char *jsonStr = cJSON_PrintUnformatted( root );
printf( "%s\n", jsonStr );
cJSON_Delete( root );
}
else {
// print out our column headers...
printf( "\n%-8s%3s %3s %3s %3s %5s %-20s%-8s%-15sFlags\n", "GNSS", "ID", "CNo", "El", "Azi", "PRr", "Signal qual", "Sat Hlt", "Orbit Src" );
printf( "%-8s%3s %3s %3s %3s %5s %-20s%-8s%-15s=====\n", "=======", "===", "===", "===", "===", "=====", "===================", "=======", "==============" );
// now print out all our satellites...
for( int i = 0; i < satellites.numberOfSatellites; i++ ) {
// build up our flags string...
ubxSatellite* s = satellites.satellites + i;
char* flags = NULL;
if( s->used ) append( &flags, "u" );
if( s->diffCorr ) append( &flags, "d" );
if( s->smoothed ) append( &flags, "s" );
if( s->haveEphemeris ) append( &flags, "e" );
if( s->haveAlmanac ) append( &flags, "a" );
if( s->sbasCorrUsed ) append( &flags, "S" );
if( s->rtcmCorrUsed ) append( &flags, "R" );
if( s->prCorrUsed ) append( &flags, "P" );
if( s->crCorrUsed ) append( &flags, "C" );
if( s->doCorrUsed ) append( &flags, "D" );
if( flags == NULL ) append( &flags, "" );
// print our satellite line...
printf( "%-8s%3d %3d %3d %3d %5.1f %-20s%-8s%-15s%s\n",
getGnssName( s->gnssID ), s->satelliteID, s->cno, s->elevation, s->azimuth, s->pseudoRangeResidualM,
getSignalQuality( s->signalQuality ), getSatelliteHealth( s->health ), getOrbitSource( s->orbitSource ), flags );
free( flags );
}
printf( "\nFlags:\n"
" u - used for navigation fix\n"
" d - differential correction is available\n"
" s - carrier-smoothed pseudorange used\n"
" e - ephemeris is available\n"
" a - almanac is available\n"
" S - SBAS corrections used\n"
" R - RTCM corrections used\n"
" P - pseudorange corrections used\n"
" C - carrier range corrections used\n"
" D - range rate (Doppler) corrections used\n"
);
}
// free up the memory we allocated...
free( satellites.satellites );
return makeOkReturn();
}
// Outputs a configuration query, in English or JSON.
static slReturn doConfigQuery( const clientData_slOptions* clientData ) {
ubxConfig config = {}; // zeroes all elements...
slReturn result = ubxGetConfig( clientData->fdPort, clientData->verbosity, &config );
if( isErrorReturn( result ) )
return makeErrorMsgReturn(ERR_CAUSE( result ), "Problem obtaining configuration information from GPS" );
if( clientData->json ) {
cJSON* root = cJSON_CreateObject();
cJSON* ant = cJSON_CreateObject();
cJSON* gnss = cJSON_CreateObject();
cJSON* gnssRecs = cJSON_CreateArray();
cJSON* nav = cJSON_CreateObject();
cJSON* time = cJSON_CreateObject();
cJSON* rate = cJSON_CreateObject();
cJSON* pwr = cJSON_CreateObject();
cJSON_AddItemToObject( root, "antenna", ant );
cJSON_AddItemToObject( root, "GNSS", gnss );
cJSON_AddItemToObject( gnss, "GNSS_records", gnssRecs );
cJSON_AddItemToObject( root, "navigation", nav );
cJSON_AddItemToObject( root, "time_pulse", time );
cJSON_AddItemToObject( root, "fix_rate", rate );
cJSON_AddItemToObject( root, "power_mode", pwr );
cJSON_AddBoolToObject( ant, "power_on", config.antPwr );
cJSON_AddBoolToObject( ant, "short_detection", config.antShrtDet );
cJSON_AddBoolToObject( ant, "open_detection", config.antOpenDet );
cJSON_AddBoolToObject( ant, "power_down_on_short", config.antPwrDwnOnShrt );
cJSON_AddBoolToObject( ant, "auto_recover_from_short", config.antAutoRec );
cJSON_AddNumberToObject( gnss, "number_of_tracking_channels", config.trkChnnls );
for( int i = 0; i < config.gnssRecs; i++ ) {
cJSON* gnssRec = cJSON_CreateObject();
cJSON_AddStringToObject( gnssRec, "name", getGnssName( config.gnss[i].id ) );
cJSON_AddBoolToObject( gnssRec, "enabled", config.gnss[i].enabled );
cJSON_AddNumberToObject( gnssRec, "min_channels", config.gnss[i].minChnnls );
cJSON_AddNumberToObject( gnssRec, "max_channels", config.gnss[i].maxChnnls );
cJSON_AddItemToArray( gnssRecs, gnssRec );
}
cJSON_AddStringToObject( nav, "dynamic_model", getDynamicModelName( config.model ) );
cJSON_AddStringToObject( nav, "fix_mode", getFixModeName( config.mode ) );
cJSON_AddNumberToObject( nav, "fixed_altitude_2D_meters", config.fixedAltM );
cJSON_AddNumberToObject( nav, "fixed_altitude_2D_variance_m2", config.fixedAltVarM2 );
cJSON_AddNumberToObject( nav, "min_elevation", config.minElevDeg );
cJSON_AddNumberToObject( nav, "position_dop_mask", config.pDoP );
cJSON_AddNumberToObject( nav, "time_dop_mask", config.tDoP );
cJSON_AddNumberToObject( nav, "position_accuracy_mask", config.pAccM );
cJSON_AddNumberToObject( nav, "time_accuracy_mask", config.tAccM );
cJSON_AddNumberToObject( nav, "static_hold_threshold_cms", config.staticHoldThreshCmS );
cJSON_AddNumberToObject( nav, "dgnss_timeout_secs", config.dgnssTimeoutS );
cJSON_AddNumberToObject( nav, "threshold_satellites_above_cno", config.cnoThreshNumSVs );
cJSON_AddNumberToObject( nav, "cno_threshold_dbhz", config.cnoThreshDbHz );
cJSON_AddNumberToObject( nav, "static_hold_max_distance_meters", config.staticHoldMaxDistM );
cJSON_AddStringToObject( nav, "utc_standard", getUTCTypeName( config.utcStandard ) );
cJSON_AddBoolToObject( time, "enabled", config.timePulse0Enabled );
cJSON_AddBoolToObject( time, "is_freq", config.isFreq );
cJSON_AddBoolToObject( time, "is_length", config.isLength );
cJSON_AddBoolToObject( time, "lock_on_gps_freq", config.lockGpsFreq );
cJSON_AddBoolToObject( time, "locked_other_set", config.lockedOtherSet );
cJSON_AddBoolToObject( time, "align_to_top_of_second", config.alignToTow );
cJSON_AddBoolToObject( time, "polarity_rising_edge", config.polarity );
cJSON_AddStringToObject( time, "time_grid", getTimeGridTypeName( config.gridUtcTnss ) );
cJSON_AddNumberToObject( time, "antenna_cable_delay_ns", config.antCableDelayNs );
cJSON_AddNumberToObject( time, "rf_group_delay_ns", config.rfGroupDelayNs );
cJSON_AddNumberToObject( time, "user_configured_delay_ns", config.userConfigDelay );
cJSON_AddNumberToObject( time, "freq_period_lock", config.freqPeriodLock * (config.isFreq ? 1 : 0.000001) );
cJSON_AddNumberToObject( time, "freq_period", config.freqPeriod * (config.isFreq ? 1 : 0.000001) );
cJSON_AddNumberToObject( time, "pulse_length_ratio_lock", config.pulseLenRatioLock * (config.isLength ? 0.000001 : 0.000000023283064) );
cJSON_AddNumberToObject( time, "pulse_length_ratio", config.pulseLenRatio * (config.isLength ? 0.000001 : 0.000000023283064) );
cJSON_AddNumberToObject( rate, "measurement_rate_ms", config.measRateMs );
cJSON_AddNumberToObject( rate, "measurements_per_fix", config.navRate );
cJSON_AddStringToObject( rate, "time_reference", getFixTimeRefName( config.timeRef ) );
cJSON_AddStringToObject( pwr, "power_setup", getPowerModeName( config.powerSetup ) );
cJSON_AddNumberToObject( pwr, "period_secs_for_interval", config.powerIntervalSecs );
cJSON_AddNumberToObject( pwr, "on_time_secs_for_interval", config.powerOnTimeSecs );
char *jsonStr = cJSON_PrintUnformatted( root );
printf( "%s\n", jsonStr );
cJSON_Delete( root );
}
else {
printf( "U-Blox GPS configuration\n" );
printf( " Antenna:\n" );
printf( " Power enabled: %s\n", yesNo( config.antPwr ) );
printf( " Short detection: %s\n", yesNo( config.antShrtDet ) );
printf( " Open detection: %s\n", yesNo( config.antOpenDet ) );
printf( " Power down on short: %s\n", yesNo( config.antPwrDwnOnShrt ) );
printf( " Auto recovery from short: %s\n", yesNo( config.antAutoRec ) );
printf( " GNSS:\n" );
printf( " Tracking channels: %d\n", config.trkChnnls );
for( int i = 0; i < config.gnssRecs; i++ ) {
printf( " Type: %s\n", getGnssName( config.gnss[i].id ) );
printf( " Enabled: %s\n", yesNo( config.gnss[i].enabled ) );
printf( " Minimum channels: %d\n", config.gnss[i].minChnnls );
printf( " Maximum channels: %d\n", config.gnss[i].maxChnnls );
}
printf( " Navigation engine:\n" );
printf( " Dynamic model: %s\n", getDynamicModelName( config.model ) );
printf( " Fix mode: %s\n", getFixModeName( config.mode ) );
printf( " Fixed altitude (2D): %.2f meters\n", config.fixedAltM );
printf( " Fixed altitude variance (2D): %.4f meters^2\n", config.fixedAltVarM2 );
printf( " Minimum elevation: %d degrees\n", config.minElevDeg );
printf( " Position DoP mask: %.1f\n", config.pDoP );
printf( " Time DoP mask: %.1f\n", config.tDoP );
printf( " Position accuracy mask: %d meters\n", config.pAccM );
printf( " Time accuracy mask: %d meters\n", config.tAccM );
printf( " Static hold threshold: %d cm/s\n", config.staticHoldThreshCmS );
printf( " Dynamic GNSS timeout: %d seconds\n", config.dgnssTimeoutS );
printf( " Threshold above C/No: %d satellites\n", config.cnoThreshNumSVs );
printf( " C/No threshold: %d dBHz\n", config.cnoThreshDbHz );
printf( " Static hold max distance: %d meters\n", config.staticHoldMaxDistM );
printf( " UTC standard: %s\n", getUTCTypeName( config.utcStandard ) );
printf( " Time pulse:\n" );
printf( " Time pulse 0 enabled: %s\n", yesNo( config.timePulse0Enabled ) );
printf( " Use frequency vs. period: %s\n", yesNo( config.isFreq ) );
printf( " Use length vs. duty cycle: %s\n", yesNo( config.isLength ) );
printf( " Lock on GPS frequency: %s\n", yesNo( config.lockGpsFreq ) );
printf( " Lock use other set: %s\n", yesNo( config.lockedOtherSet ) );
printf( " Align to top of second: %s\n", yesNo( config.alignToTow ) );
printf( " Polarity rising edge: %s\n", yesNo( config.polarity ) );
printf( " Time grid: %s\n", getTimeGridTypeName( config.gridUtcTnss ) );
printf( " Antenna cable delay: %d nanoseconds\n", config.antCableDelayNs );
printf( " RF group delay: %d nanoseconds\n", config.rfGroupDelayNs );
if( config.isFreq ) {
printf( " Locked pulse frequency: %d Hz\n", config.freqPeriodLock );
printf( " Unlocked pulse frequency: %d Hz\n", config.freqPeriod );
} else {
printf( " Locked pulse period: %d microseconds\n", config.freqPeriodLock );
printf( " Unlocked pulse period: %d microseconds\n", config.freqPeriod );
}
if( config.isLength ) {
printf( " Locked pulse length: %d microseconds\n", config.pulseLenRatioLock );
printf( " Unlocked pulse length: %d microseconds\n", config.pulseLenRatio );
} else {
printf( " Locked pulse duty cycle: %.2f%%\n", config.pulseLenRatioLock * 0.000000023283064 );
printf( " Unlocked pulse duty cycle: %.2f%%\n", config.pulseLenRatio * 0.000000023283064 );
}
printf( " User configurable delay: %d nanoseconds\n", config.userConfigDelay );
printf( " Fix rate:\n" );
printf( " Measurement rate: %d milliseconds\n", config.measRateMs );
printf( " Measurements per fix: %d\n", config.navRate );
printf( " Time reference: %s\n", getFixTimeRefName( config.timeRef ) );
printf( " Power mode:\n" );
printf( " Power setup: %s\n", getPowerModeName( config.powerSetup ) );
printf( " Period (if interval): %d seconds\n", config.powerIntervalSecs );
printf( " On time (if interval): %d seconds\n", config.powerOnTimeSecs );
}
return makeOkReturn();
}
static slReturn parseMsgHelper( errorInfo_slReturn error, const optionDef_slOptions* def, char *pattern, ... ) {
char* resolved;
// first resolve the pattern we were given...
va_list args;
va_start( args, pattern );
vasprintf( &resolved, pattern, args );
va_end( args );
// return our bad news...
slReturn result = makeErrorFmtMsgReturn( error, "option parsing problem: [%s] %s", getName_slOptions( def ), resolved );
free( resolved );
return result;
}
// Test the argument to see if it represents a valid serial port. On failure, return an error.
static slReturn parsePort( void* ptrArg, int intArg, const optionDef_slOptions *def, const char *arg, clientData_slOptions *clientData ) {
slReturn vsd = verifySerialDevice( arg );
if( isErrorReturn( vsd ) )
return makeErrorFmtMsgReturn(ERR_CAUSE( vsd ), "device \"%s\" is not a terminal", arg );
return makeOkReturn();
}
// Parse the given argument, which is presumed to be a string representing a positive integer that is one of the
// standard baud rates. If the parsing fails for any reason, return an error
static slReturn parseBaud( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// make sure we can parse the entire argument into an integer...
char *endPtr;
int baud = (int) strtol( arg, &endPtr, 10 );
if( *endPtr != 0 )
return parseMsgHelper(ERR_ROOT, def, "the specified baud rate (\"%s\") is not an integer", arg );
// make sure the result is a valid baud rate...
if( getBaudRateCookie( baud ) < 0 )
return parseMsgHelper(ERR_ROOT, def, "the specified baud rate (\"%s\") is not a valid one (4800, 9600, 19200, etc.)", arg );
// we have a valid baud rate, so stuff it away and return in victory...
*((int*)ptrArg) = baud;
return makeOkReturn();
}
// Parse autobaud or sync, which have an optional argument of ascii, nmea, or ubx.
static slReturn parseSyncMethod( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// set up the sync method...
slReturn ssmResp = setSyncMethod( arg, clientData );
if( isErrorReturn( ssmResp ) )
return parseMsgHelper(ERR_CAUSE( ssmResp ), def, "the specified baud rate inference method (\"%s\") is unrecognizable; should be \"ascii\", \"nmea\", or \"ubx\"", arg );
return makeOkReturn();
}
// Parse the given argument, which is presumed to be a string representing a yes or no value, which if parsed without
// error is stored to the argPtr. If the parsing fails for any reason, return an error.
static slReturn parseBool( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// see if we've got anything that like a yes or true (otherwise, we make it a false)...
*((bool*)ptrArg) = (arg == NULL) ? false : (strchr( "yYtT1", *arg ) != NULL);
// then return with no error...
return makeOkReturn();
}
// Parse the given argument, which is presumed to be a string representing an integer, which if parsed without error is
// stored to the argPtr. If the parsing fails for any reason, return an error.
static slReturn parseInt( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// make sure we can parse the entire argument into an integer...
int n = 0;
if( arg != NULL ) {
char *endPtr;
n = (int) strtol(arg, &endPtr, 10);
if (*endPtr != 0)
return parseMsgHelper(ERR_ROOT, def, "the specified %s (\"%s\") is not an integer", def->argName, arg);
}
// stuff it away to the given pointer...
*((int*)ptrArg) = n;
// then return with no error...
return makeOkReturn();
}
// Set a boolean flag at the given ptrArg to the given intArg.
static slReturn parseFlag( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// do what we've been told to do...
*((bool*)ptrArg) = (bool) intArg;
// then return with no error...
return makeOkReturn();
}
typedef struct { char* name; queryType queryType; } queryDef;
static queryDef queryDefs[] = {
{ "fix", fixQuery },
{ "version", versionQuery },
{ "satellites", satelliteQuery },
{ "config", configQuery }
};
// Parse the given query type and store the results. Returns an error on any parsing problem.
static slReturn parseQuery( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// see what kind of query we've got here...
for( int i = 0; i < ARRAY_SIZE( queryDefs ); i++ ) {
if( 0 == strcmp( arg, queryDefs[i].name ) ) {
clientData->queryType = queryDefs[i].queryType;
return makeOkReturn();
}
}
// if we get here then we have a bogus query type...
return parseMsgHelper(ERR_ROOT, def, "the specified %s (\"%s\") is not a valid query type", def->argName, arg );
}
// Increment the int counter at the given ptrArg.
static slReturn parseCount( void* ptrArg, int intArg, const optionDef_slOptions* def, const char* arg, clientData_slOptions* clientData ) {
// do what we've been told to do...
(*((int*)ptrArg))++;
// then return with no error...
return makeOkReturn();
}
#undef V3
#undef V2
#undef V1
#undef V0
#undef CD
// Sync may only be specified if auto baud rate was NOT specified...
static slReturn constrainSync( const optionDef_slOptions* defs, const psloConfig* config, const state_slOptions* state ) {
if( hasShortOption_slOptions( 'a', state ) )
return makeErrorMsgReturn(ERR_ROOT, "-s, --sync may only be specified if -a, --autobaud is NOT specified" );
return makeOkReturn();
}
// JSON may only be specified if a query was specified...
static slReturn constrainJSON( const optionDef_slOptions* defs, const psloConfig* config, const state_slOptions* state ) {
if( !hasShortOption_slOptions( 'Q', state ) )
return makeErrorMsgReturn(ERR_ROOT, "-j, --json may only be specified if -Q, --query is also specified" );
return makeOkReturn();
}
// Baud may only be specified if auto baud rate was NOT specified...
static slReturn constrainBaud( const optionDef_slOptions* defs, const psloConfig* config, const state_slOptions* state ) {
if( hasShortOption_slOptions( 'a', state ) )
return makeErrorMsgReturn(ERR_ROOT, "-b, --baud may only be specified if -a, --autobaud is NOT specified" );
return makeOkReturn();
}
// Minbaud may only be specified if auto baud rate was specified...
static slReturn constrainMinBaud( const optionDef_slOptions* defs, const psloConfig* config, const state_slOptions* state ) {
if( !hasShortOption_slOptions( 'a', state ) )
return makeErrorMsgReturn(ERR_ROOT, "-M, --minbaud may only be specified if -a, --autobaud is also specified" );
return makeOkReturn();
}
// Verbosity may only be specified if quiet was NOT specified...
static slReturn constrainVerbosity( const optionDef_slOptions* defs, const psloConfig* config, const state_slOptions* state ) {
if( hasShortOption_slOptions( 'q', state ) )
return makeErrorMsgReturn(ERR_ROOT, "-v, --verbosity d may only be specified if -q, --quiet is NOT specified" );
return makeOkReturn();
}
#define CD (config->clientData)
#define V0 (CD->verbosity >= 0)
#define V1 (CD->verbosity >= 1)
#define V2 (CD->verbosity >= 2)
#define V3 (CD->verbosity >= 3)
// Setup action function, which opens and configures the serial port.
static slReturn actionSetup( const optionDef_slOptions* defs, const psloConfig* config ) {
// first we try opening the device for the port...
int fdPort = open( CD->port, O_RDWR | O_NOCTTY | O_NONBLOCK );
if( fdPort < 0 ) {
printf( "Failed to open serial port: %s\n", strerror( errno ) );
exit(1);
}
if( V2 ) printf( "Serial port (\"%s\") open...\n", CD->port );
// stuff our file descriptor and return in victory...
CD->fdPort = fdPort;
if( V2 ) printf( "Serial port open and configured...\n" );
return makeOkReturn();
}
// Teardown action function, which closes the serial port.
static slReturn actionTeardown( const optionDef_slOptions* defs, const psloConfig* config ) {
close( CD->fdPort );
return makeOkReturn();
}
// Test for the presence and quality of a 1 Hz signal on GPIO 18 (the PPS signal from the GPS), printing the result.
#define PPS_PIN 1
static slReturn actionTestPPS( const optionDef_slOptions* defs, const psloConfig* config ) {
wiringPiSetup();
pinMode( PPS_PIN, INPUT );
struct timespec tenmicro = { 0, 10000 };
struct timespec lastTime = { 0, 0 };
// measure for about 10 seconds...
int lastState = 0;
for( int i = 0; i < 100000; i++ ) {
// wait 10 microseconds
nanosleep( &tenmicro, NULL );
// check our state...
int state = digitalRead( PPS_PIN );
// if the state has changed, time to measure and report...
if(state != lastState ) {
// get the current time...
struct timespec thisTime;
int result = clock_gettime( CLOCK_MONOTONIC, &thisTime );
if( result != 0 )
return makeErrorFmtMsgReturn( ERR_ROOT, "problem reading CPU clock: %s", strerror( errno ) );
// if this isn't our first measurement...
if( (lastTime.tv_sec != 0 ) || (lastTime.tv_nsec != 0) ) {
// figure out how long we were in this state...
long long nanos = thisTime.tv_nsec - lastTime.tv_nsec;
if( nanos < 0 ) nanos += 1000000000;
double secs = 1.0 * nanos / 1000000000.0;
// tell our results...
char* signal = (lastState == 0) ? " low" : "high";
printf( "PPS was %s for %.3f seconds\n", signal, secs );
}
lastTime = thisTime;
lastState = state;
}
}
return makeOkReturn();
}
// Autobaud action function, which infers the GPS baud rate by trying to synchronize at various baud rates.
static slReturn actionAutoBaud( const optionDef_slOptions* defs, const psloConfig* config ) {
// first we figure out what synchronization type we're going to use...
baudRateSynchronizer* synchronizer;
clientData_slOptions* cd = config->clientData;
switch( cd->syncMethod ) {
case syncASCII:
synchronizer = asciiBaudRateSynchronizer;
break;
case syncNMEA:
synchronizer = nmeaBaudRateSynchronizer;
break;
case syncUBX:
synchronizer = ubxSynchronizer;
break;
default: return makeErrorFmtMsgReturn( ERR_ROOT, "invalid synchronization type: %d", cd->syncMethod );
}
if( V2 ) printf( "Automatically determining baud rate...\n");
// now we set the correct options (the first baud rate, 8 data bits, 1 stop bit, no parity)
slReturn result = setTermOptions( CD->fdPort, 230400, 8, 1, false, false );
if( isErrorReturn( result ) ) {
close(CD->fdPort );
return makeErrorMsgReturn(ERR_CAUSE( result ), "Error when setting terminal options" );
}
// now we do the actual work...
slReturn abResp = autoBaudRate( cd->fdPort, cd->minBaud, synchronizer, cd->verbosity );
if( isErrorReturn( abResp ) )
makeErrorFmtMsgReturn( ERR_CAUSE( abResp ), "problem while automatically determining baud rate" );
// change the client data to reflect the new baud rate...
cd->baud = cd->newbaud;
return makeOkReturn();
}
// Baud action function, which sets the host's port to the specified baud rate.
static slReturn actionBaud( const optionDef_slOptions* defs, const psloConfig* config ) {
if( V2 ) printf( "Setting baud rate to %d...\n", CD->baud );
// now we set the correct options (the specified baud rate, 8 data bits, 1 stop bit, no parity)
slReturn result = setTermOptions( CD->fdPort, CD->baud, 8, 1, false, false );
if( isErrorReturn( result ) ) {
close(CD->fdPort );
return makeErrorMsgReturn(ERR_CAUSE( result ), "Error when setting terminal options" );
}
return makeOkReturn();
}
// New baud rate action function, which changes both the U-Blox GPS baud rate and the host baud rate.
static slReturn actionNewBaud( const optionDef_slOptions* defs, const psloConfig* config ) {
clientData_slOptions* cd = config->clientData;
if( V2 ) printf( "Changing baud rate to %d...\n", cd->newbaud );
slReturn resp = ubxChangeBaudRate( cd->fdPort, (unsigned) cd->newbaud, cd->verbosity );
if( isErrorReturn( resp ) )
return makeErrorMsgReturn(ERR_CAUSE( resp ), "failed to change baud rate" );
return makeOkReturn();
}
// Sync action function, which synchronizes serial port receiver with the data stream using the configured method.
static slReturn actionSync( const optionDef_slOptions* defs, const psloConfig* config ) {
slReturn ssResp = syncSerial( CD->syncMethod, config->clientData );
if( isErrorReturn( ssResp ) )
return makeErrorMsgReturn( ERR_CAUSE( ssResp ), "error while synchronizing on serial data" );
bool success = getReturnInfoChar( ssResp );
if( success )
return makeOkReturn();
else
return makeErrorMsgReturn(ERR_ROOT, "failed to synchronize" );
}
// NMEA action function, which turns NMEA data on or off on the U-Blox GPS.
static slReturn actionNMEA( const optionDef_slOptions* defs, const psloConfig* config ) {
clientData_slOptions* clientData = config->clientData;
slReturn usResp = syncSerial( syncUBX, clientData );
if( isErrorReturn( usResp ) )
return makeErrorMsgReturn( ERR_CAUSE( usResp ), "could not synchronize UBX protocol" );
slReturn resp = ubxSetNMEAData( clientData->fdPort, clientData->verbosity, clientData->nmea );
if( isErrorReturn( resp ) )
return makeErrorFmtMsgReturn(ERR_CAUSE( resp ), "failed to turn NMEA data %s", clientData->nmea ? "on" : "off" );
return makeOkReturn();
}
// Query action function, which queries the U-Blox GPS for the specified data.
static slReturn actionQuery( const optionDef_slOptions* defs, const psloConfig* config ) {
clientData_slOptions* clientData = config->clientData;
slReturn usResp = syncSerial( syncUBX, clientData );
if( isErrorReturn( usResp ) )
return makeErrorMsgReturn( ERR_CAUSE( usResp ), "could not synchronize UBX protocol" );
slReturn resp;
switch( clientData->queryType ) {
case fixQuery: resp = doFixQuery( clientData ); break;
case versionQuery: resp = doVersionQuery( clientData ); break;
case configQuery: resp = doConfigQuery( clientData ); break;
case satelliteQuery: resp = doSatelliteQuery( clientData ); break;
default: return makeErrorFmtMsgReturn(ERR_ROOT, "invalid query type: %d", clientData->queryType );
}
if( isErrorReturn( resp ) )
return makeErrorMsgReturn(ERR_CAUSE( resp ), "problem executing GPS query" );
return makeOkReturn();
}
// Save configuration action function, which saves the current U-Blox GPS configuration to battery-backed RAM.
static slReturn actionSaveConfig( const optionDef_slOptions* defs, const psloConfig* config ) {
// make sure we're synchronized...
clientData_slOptions* clientData = config->clientData;
slReturn usResp = syncSerial( syncUBX, clientData );
if( isErrorReturn( usResp ) )
return makeErrorMsgReturn( ERR_CAUSE( usResp ), "could not synchronize UBX protocol" );