diff options
| -rw-r--r-- | subframe.c | 47 |
1 files changed, 35 insertions, 12 deletions
@@ -86,7 +86,15 @@ struct almanac uint16_t e; int16_t Omegad; uint32_t toa, svh, sqrtA; - int32_t deltai, Omega0, omega, M0, af0, af1; + int32_t deltai, Omega0, omega, M0; + /* af0, SV clock correction constant term + * 11 bits signed, seconds */ + int16_t af0; + double d_af0; + /* af1, SV clock correction first order term + * 11 bits signed, seconds/second */ + int16_t af1; + double d_af1; /* eccentricity, 16 bits, unsigned, dimensionless */ double d_eccentricity; /* sqrt A, Square Root of the Semi-Major Axis @@ -126,14 +134,16 @@ static void subframe_almanac(unsigned int svid, uint32_t words[], almp->M0 = uint2int(almp->M0, BIT24); almp->af1 = ((words[9] >> 5) & 0x0007FF); almp->af1 = uint2int(almp->af1, BIT11); + almp->d_af1 = pow(2.0,-38) * almp->af1; almp->af0 = ((words[9] >> 16) & 0x0000FF); almp->af0 <<= 3; almp->af0 |= ((words[9] >> 2) & 0x000007); almp->af0 = uint2int(almp->af0, BIT11); + almp->d_af0 = pow(2.0,-20) * almp->af0; gpsd_report(LOG_PROG, "50B: SF:%d SV:%2u TSV:%2u data_id %d e:%g toa:%u deltai:%d" " Omegad:%.5g svh:%u sqrtA:%.8g Omega0:%d omega:%d M0:%d" - " af0:%d af1:%d\n", + " af0:%.5e af1:%.5e\n", subframe, sv, svid, data_id, almp->d_eccentricity, almp->toa, @@ -144,8 +154,8 @@ static void subframe_almanac(unsigned int svid, uint32_t words[], almp->Omega0, almp->omega, almp->M0, - almp->af0, - almp->af1); + almp->d_af0, + almp->d_af1); } struct subframe { @@ -153,7 +163,19 @@ struct subframe { union { struct { unsigned int l2, ura, hlth, iodc, toc, l2p; - int32_t tgd, af0, af1, af2; + /* af0, SV clock correction constant term + * 22 bits signed, seconds */ + int32_t af0; + double d_af0; + /* af1, SV clock correction first order term + * 22 bits signed, seconds/second */ + int16_t af1; + double d_af1; + /* af2, SV clock correction second order term + * 8 bits signed, seconds/second**2 */ + int8_t af2; + double d_af2; + int32_t tgd; } sub1; struct { /* Issue of Data (Ephemeris), @@ -256,16 +278,17 @@ void gpsd_interpret_subframe(struct gps_device_t *session, subp->sub1.tgd = uint2int(subp->sub1.tgd, BIT8); subp->sub1.toc = ( words[7] & 0x00FFFF); subp->sub1.af2 = ((words[8] >> 16) & 0x0FF); - subp->sub1.af2 = uint2int(subp->sub1.af2, BIT8); + subp->sub1.d_af2 = pow(2.0, -55) * subp->sub1.af2; subp->sub1.af1 = ( words[8] & 0x00FFFF); - subp->sub1.af1 = uint2int(subp->sub1.af1, BIT16); + subp->sub1.d_af1 = pow(2.0, -43) * subp->sub1.af1; subp->sub1.af0 = ((words[9] >> 1) & 0x03FFFFF); subp->sub1.af0 = uint2int(subp->sub1.af0, BIT22); + subp->sub1.d_af0 = pow(2.0, -31) * subp->sub1.af0; subp->sub1.iodc <<= 8; subp->sub1.iodc |= ((words[7] >> 16) & 0x00FF); gpsd_report(LOG_PROG, "50B: SF:1 SV:%2u WN:%4u IODC:%4u" - " L2:%u ura:%u hlth:%u L2P:%u Tgd:%d toc:%u af2:%3d" - " af1:%5d af0:%7d\n", svid, + " L2:%u ura:%u hlth:%u L2P:%u Tgd:%d toc:%u af2:%.4g" + " af1:%.6e af0:%.7e\n", svid, session->context->gps_week, subp->sub1.iodc, subp->sub1.l2, @@ -274,9 +297,9 @@ void gpsd_interpret_subframe(struct gps_device_t *session, subp->sub1.l2p, subp->sub1.tgd, subp->sub1.toc, - subp->sub1.af2, - subp->sub1.af1, - subp->sub1.af0); + subp->sub1.d_af2, + subp->sub1.d_af1, + subp->sub1.d_af0); } break; case 2: |