summaryrefslogtreecommitdiff
path: root/mbglib/common/mbgextio.c
blob: 53b2486c3487246e4214f22d52988c44933cfd9b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510

/**************************************************************************
 *
 *  $Id: mbgextio.c 1.11 2011/04/15 13:17:14 martin REL_M $
 *
 *  Copyright (c) Meinberg Funkuhren, Bad Pyrmont, Germany
 *
 *  Description:
 *    Meinberg extended I/O functions for the binary data protocol
 *    via serial communication and network socket I/O.
 *
 * -----------------------------------------------------------------------
 *  $Log: mbgextio.c $
 *  Revision 1.11  2011/04/15 13:17:14  martin
 *  Use common mutex support macros from mbgmutex.h.
 *  Revision 1.10  2011/04/08 11:28:24  martin
 *  Modified mbgextio_get_ucap() to account for different device behaviour.
 *  Added missing braces.
 *  Revision 1.9  2009/10/02 14:19:05  martin
 *  Added a bunch of missing functions.
 *  Revision 1.8  2009/10/01 11:10:51  martin
 *  Added functions to set/retrieve char and msg rcv timeout.
 *  Revision 1.7  2009/09/01 10:44:58  martin
 *  Cleanup for CVI.
 *  Use new portable timeout functions from mbg_tmo.h.
 *  Timeouts are now specified in milliseconds.
 *  Distinguish between character timeout and message timeout.
 *  Only fetch one character at a time to prevent received characters
 *  from being discarded after the end of one message.
 *  Revision 1.6  2009/03/10 17:02:08Z  martin
 *  Added support for configurable time scales.
 *  Added mbgextio_get_time() call.
 *  Fixed some compiler warnings.
 *  Revision 1.5  2008/09/04 14:35:50Z  martin
 *  Fixed opening COM port under CVI.
 *  Moved generic serial I/O stuff to mbgserio.c and mbgserio.h.
 *  Restart reception if received msg does not match expected cmd code.
 *  Fixed timeout value for Windows.
 *  New symbol _MBGEXTIO_DIRECT_RC controls whether the return code of the 
 *  mbgextio_set_...() functions is evaluated or returned as-is.
 *  New functions mbgextio_set_time(), mbgextio_set_tzdl().
 *  Added mbgextio_get_ucap(). This may not work with older firmware,
 *  see the comments in mbgextio_get_ucap().
 *  Conditionally support checking of time strings.
 *  Revision 1.4  2007/02/27 10:35:19Z  martin
 *  Added mutex for transmit buffer to make transmission thread-safe.
 *  Fixed timeout handling for serial reception.
 *  Renamed mbgextio_get_data() to mbgextio_rcv_msg().
 *  Added some new functions.
 *  Temp. changes for parameter setting functions.
 *  Added comments on POSIX flags used when opening serial port.
 *  Revision 1.3  2006/12/21 10:56:17  martin
 *  Added function mbgextio_set_port_parm.
 *  Revision 1.2  2006/10/25 12:18:31  martin
 *  Support serial I/O under Windows.
 *  Revision 1.1  2006/08/24 12:40:37Z  martin
 *  Initial revision.
 *
 **************************************************************************/

#define _MBGEXTIO
  #include <mbgextio.h>

  //##++ The following lines are required
  //     until mbgextio becomes a DLL:
  #undef _MBG_API_ATTR
  #define _MBG_API_ATTR
#undef _MBGEXTIO

#include <mbgserio.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <gpsutils.h>

#if defined( MBG_TGT_UNIX )
  #include <unistd.h>
  #include <fcntl.h>
#else
  typedef int ssize_t;
#endif

#if !defined( MBGEXTIO_DIRECT_RC )
  #define _MBGEXTIO_DIRECT_RC     0  //##++ 1
#endif


// default serial message timeout
#if !defined ( MBGEXTIO_MSG_RCV_TIMEOUT_SERIAL )
  #define MBGEXTIO_MSG_RCV_TIMEOUT_SERIAL     3000  // [ms]
#endif

// default serial single character timeout
#if !defined ( MBGEXTIO_CHAR_RCV_TIMEOUT_SERIAL )
  #define MBGEXTIO_CHAR_RCV_TIMEOUT_SERIAL     200  // [ms]
#endif


#if defined( MBG_TGT_WIN32 ) && _USE_SOCKET_IO

static /*HDR*/
BOOL WINAPI mbgextio_on_console_event( DWORD dwCtrlType )
{
  switch ( dwCtrlType )
  {
    case CTRL_BREAK_EVENT:
    case CTRL_C_EVENT:
    case CTRL_CLOSE_EVENT:
    case CTRL_SHUTDOWN_EVENT:
      exit( 0 );

  }  // switch

  return FALSE;

}  // mbgextio_on_console_event



static /*HDR*/
void mbgextio_set_console_control_handler( void )
{
  static int has_been_set;

  if ( !has_been_set )
  {
    SetConsoleCtrlHandler( mbgextio_on_console_event, TRUE );
    has_been_set = 1;
  }

}  // mbgextio_set_console_control_handler

#endif  //  defined MBG_TGT_WIN32




#if _USE_SOCKET_IO

static /*HDR*/
int socket_init( MBG_MSG_CTL *pmctl, const char *host )
{
  struct hostent *hp;
  struct sockaddr_in *paddr;
  const struct sockaddr *p;
  int sz;
  int rc;

  hp = gethostbyname( host );

  #if defined( MBG_TGT_WIN32 )
    if ( hp == NULL )
    {
      // The winsock2.dll may not yet have been initialized,
      // so try to initialize now.
      WORD wVersionRequested;
      WSADATA wsaData;

      wVersionRequested = MAKEWORD( 2, 2 );

      rc = WSAStartup( wVersionRequested, &wsaData );

      // If initialization has succeeded, try again.
      if ( rc == 0 )
        hp = gethostbyname( host );
    }
  #endif  // defined( MBG_TGT_WIN32 )

  if ( hp == NULL )
    return TR_OPEN_ERR;


  // create socket on which to send.
  pmctl->st.sockio.sockfd = socket( PF_INET, SOCK_STREAM, 0 );

  if ( pmctl->st.sockio.sockfd == INVALID_SOCKET )
    return TR_OPEN_ERR;

  paddr = &pmctl->st.sockio.addr;
  memset( paddr, 0, sizeof( *paddr ) );

  memcpy( &paddr->sin_addr, hp->h_addr, hp->h_length );
  paddr->sin_family = AF_INET;
  paddr->sin_port = htons( LAN_XPT_PORT );

  p = (const struct sockaddr *) paddr;
  sz = sizeof( *paddr );

  rc = connect( pmctl->st.sockio.sockfd, p, sz );

  if ( rc < 0 )
    return TR_OPEN_ERR;

  return 0;

}  // socket_init



static /*HDR*/
int comm_init( MBG_MSG_CTL *pmctl, const char *passwd )
{
  SECU_SETTINGS *pss = &pmctl->secu_settings;
  MBG_MSG_BUFF *pmb;
  int rc;

  memset( pss, 0, sizeof *pss );
  strncpy( pss->password, passwd, sizeof( pss->password ) );

  pmctl->conn_type = MBG_CONN_TYPE_SOCKET;
  pmctl->msg_rcv_timeout = MBGEXTIO_RCV_TIMEOUT_SOCKET;
  // pmctl->char_rcv_timeout is not used with sockets

  set_encryption_mode( pmctl, MBG_XFER_MODE_ENCRYTED, pss->password );

  pmb = pmctl->xmt.pmb;
  pmb->u.msg_data.secu_settings = *pss;
  pmb->hdr.cmd = GPS_SECU_SETTINGS;
  pmb->hdr.len = sizeof( pmb->u.msg_data.secu_settings );

  xmt_tbuff( pmctl );
  rc = mbgextio_rcv_msg( pmctl, GPS_SECU_SETTINGS );

  if ( rc != TR_COMPLETE )
    return -1;  /* connection refused */

  pmb = pmctl->rcv.pmb;

  if ( !( pmb->hdr.cmd & GPS_ACK ) )
    return -2;  /* authentication failed */

  return 0;

}  // comm_init



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_open_socket( MBG_MSG_CTL *pmctl, 
                                    const char *host, const char *passwd )
{
  int rc = socket_init( pmctl, host );

  if ( rc < 0 )
    return rc;

  comm_init( pmctl, passwd );

  #if defined( MBG_TGT_WIN32 )
    mbgextio_set_console_control_handler();
  #endif

  #if _USE_MUTEX
    _mbg_mutex_init( &pmctl->xmt.xmt_mutex );
  #endif

  return rc;

}  // mbgextio_open_socket

#endif  // _USE_SOCKET_IO



#if _USE_SERIAL_IO

/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_open_serial( MBG_MSG_CTL *pmctl, const char *dev,
                             uint32_t baud_rate, const char *framing )
{
  int rc;

  pmctl->conn_type = MBG_CONN_TYPE_SERIAL;
  pmctl->msg_rcv_timeout = MBGEXTIO_MSG_RCV_TIMEOUT_SERIAL;
  pmctl->char_rcv_timeout = MBGEXTIO_CHAR_RCV_TIMEOUT_SERIAL;

  rc = mbgserio_open( &pmctl->st.serio, dev );

  if ( rc < 0 )  //##++
    return rc;

  mbgserio_set_parms( &pmctl->st.serio, baud_rate, framing );

  #if _USE_MUTEX
    _mbg_mutex_init( &pmctl->xmt.xmt_mutex );
  #endif

  return 0;

}  // mbgextio_open_serial

#endif



/*HDR*/
_MBG_API_ATTR void _MBG_API mbgextio_close_connection( MBG_MSG_CTL *pmctl )
{
  switch ( pmctl->conn_type )
  {
    #if _USE_SERIAL_IO
      case MBG_CONN_TYPE_SERIAL:
      {
        #if defined( MBG_TGT_UNIX )
          tcsetattr( pmctl->st.serio.port_handle, TCSANOW, &pmctl->st.serio.oldtio );
        #endif

        mbgserio_close( &pmctl->st.serio );
      } break;
    #endif  // _USE_SERIAL_IO

    #if _USE_SOCKET_IO
      case MBG_CONN_TYPE_SOCKET:
      {
        _mbg_close( pmctl->st.sockio.sockfd );
        pmctl->st.sockio.sockfd = 0;
      } break;
    #endif  // _USE_SOCKET_IO

  };  // switch

  #if _USE_MUTEX
    _mbg_mutex_destroy( &pmctl->xmt.xmt_mutex );
  #endif

}  // mbgextio_close_connection



#if _USE_SERIAL_IO

/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_force_connection( const char *dev )
{
  static const char *cmd_str = "\nDFC\n";  //##++

  MBG_MSG_CTL mctl =
  {
    { NULL, 0 },
    { NULL, 0 }
  };

  int i;
  int j;
  int len = strlen( cmd_str );

  for ( i = 0; i < N_MBG_BAUD_RATES; i++ )
  {
    for ( j = 0; j < N_MBG_FRAMINGS; j++ )
    {
      uint32_t baud_rate = mbg_baud_rates[i];
      const char *framing = mbg_framing_strs[j];
      int rc = mbgextio_open_serial( &mctl, dev, baud_rate, framing );

      if ( rc != 0 ) // failed to open port
        return -1;

      _mbgserio_write( mctl.st.serio.port_handle, cmd_str, len );

      #if defined( MBG_TGT_UNIX )
        tcdrain( mctl.st.serio.port_handle );
      #elif defined( MBG_TGT_CVI )
        //##++++
      #elif defined( MBG_TGT_WIN32 )
        FlushFileBuffers( mctl.st.serio.port_handle );
      #endif

      mbgextio_close_connection( &mctl );
    }
  }

  return 0;

}  // mbgextio_force_connection

#endif  // _USE_SERIAL_IO



/*HDR*/
_MBG_API_ATTR void _MBG_API mbgextio_set_char_rcv_timeout( MBG_MSG_CTL *pmctl, ulong new_timeout )
{
  pmctl->char_rcv_timeout = new_timeout;

}  // mbgextio_set_char_rcv_timeout



/*HDR*/
_MBG_API_ATTR ulong _MBG_API mbgextio_get_char_rcv_timeout( const MBG_MSG_CTL *pmctl )
{
  return pmctl->char_rcv_timeout;

}  // mbgextio_get_char_rcv_timeout



/*HDR*/
_MBG_API_ATTR void _MBG_API mbgextio_set_msg_rcv_timeout( MBG_MSG_CTL *pmctl, ulong new_timeout )
{
  pmctl->msg_rcv_timeout = new_timeout;

}  // mbgextio_set_msg_rcv_timeout



/*HDR*/
_MBG_API_ATTR ulong _MBG_API mbgextio_get_msg_rcv_timeout( const MBG_MSG_CTL *pmctl )
{
  return pmctl->msg_rcv_timeout;

}  // mbgextio_get_msg_rcv_timeout



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_xmt_msg( MBG_MSG_CTL *pmctl, GPS_CMD cmd, 
                                             const void *p, int n_bytes )
{
  MBG_MSG_BUFF *pmb;

  if ( n_bytes > sizeof( pmb->u.msg_data ) )
    return -1;  // bytes to send exceed buffer size


  #if _USE_MUTEX
    _mbg_mutex_acquire( &pmctl->xmt.xmt_mutex );
  #endif

  pmb = pmctl->xmt.pmb;

  if ( p && n_bytes )
    memcpy( pmb->u.bytes, p, n_bytes );

  pmb->hdr.len = n_bytes;
  pmb->hdr.cmd = cmd;
  xmt_tbuff( pmctl );

  #if _USE_MUTEX
    _mbg_mutex_release( &pmctl->xmt.xmt_mutex );
  #endif

  if ( cmd & GPS_REQACK )
  {
    int rc = mbgextio_rcv_msg( pmctl, (GPS_CMD) ( cmd &  ~GPS_CTRL_MSK ) );

    if ( rc != TR_COMPLETE )
      return -2;

    if ( pmctl->rcv.pmb->hdr.cmd & GPS_NACK )
      return -3;

    if ( !(pmctl->rcv.pmb->hdr.cmd & GPS_ACK) )
      return -4;
  }


  return 0;

}  // mbgextio_xmt_msg



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_rcv_msg( MBG_MSG_CTL *pmctl, GPS_CMD cmd )
{
  MBG_MSG_RCV_CTL *prctl;
  MBG_MSG_BUFF *pmb;
  MBG_TMO_TIME msg_timeout;
  char buff[MBGEXTIO_READ_BUFFER_SIZE];
  ssize_t n_bytes;
  int rc;
  int i;

  mbg_tmo_set_timeout_ms( &msg_timeout, pmctl->msg_rcv_timeout );

  for (;;)  // loop until complete msg received
  {
    n_bytes = 0;

    if ( mbg_tmo_curr_time_is_after( &msg_timeout ) )
      return TR_TIMEOUT;

    #if _USE_SOCKET_IO
      if ( pmctl->conn_type == MBG_CONN_TYPE_SOCKET )
      {
        struct timeval tv_timeout;
        fd_set fds;

        if ( pmctl->io_error )
          return TR_IO_ERR;

        mbgserio_msec_to_timeval( pmctl->msg_rcv_timeout, &tv_timeout );

        FD_ZERO( &fds );
        FD_SET( pmctl->st.sockio.sockfd, &fds );

        rc = select( pmctl->st.sockio.sockfd + 1, &fds, NULL, NULL, &tv_timeout );

        if ( rc == 0 )    // timeout
          return TR_TIMEOUT;

        if ( rc < 0 )     // error
        {
          pmctl->io_error = 1;
          return TR_IO_ERR;
        }

        // data is available

        n_bytes = recv( pmctl->st.sockio.sockfd, buff, sizeof( buff ), 0 );

        if ( n_bytes < 0 )
        {
          pmctl->io_error = 1;
          return TR_IO_ERR;
        }
      }
    #endif  // _USE_SOCKET_IO

    #if _USE_SERIAL_IO
      if ( pmctl->conn_type == MBG_CONN_TYPE_SERIAL )
      {
        n_bytes = mbgserio_read_wait( pmctl->st.serio.port_handle, &buff[0],
                                      sizeof( buff[0] ), pmctl->char_rcv_timeout );

        if ( n_bytes < 0 )
        {
          if ( n_bytes == MBGSERIO_TIMEOUT )
             return TR_TIMEOUT;

          pmctl->io_error = 1;
          return TR_IO_ERR;
        }
      }
    #endif  // _USE_SERIAL_IO

    prctl = &pmctl->rcv;
    pmb = prctl->pmb;

    for ( i = 0; i < n_bytes; i++ )
    {
      char c = buff[i];

      /* check if the new char belongs to a data transfer sequence */
      rc = check_transfer( prctl, c );

      switch ( rc )
      {
        case TR_WAITING:      /* no data transfer sequence in progress */
          #if _USE_CHK_TSTR
            if ( prctl->chk_tstr_fnc )  /* optionally handle normal, non-protocol data */
              prctl->chk_tstr_fnc( c, prctl->chk_tstr_arg );
          #endif
          // intentional fall-through

        case TR_RECEIVING:    /* data transfer sequence in progress, keep waiting */
          continue;

        case TR_COMPLETE:
          {
            uint16_t rcvd_cmd = pmb->hdr.cmd & ~GPS_CTRL_MSK;

            if ( rcvd_cmd == cmd )  /* the received packet is what we've been waiting for */
              return TR_COMPLETE;

            #if _USE_ENCRYPTION
              /* if an encrypted packet has been received then decrypt it */
              if ( rcvd_cmd == GPS_CRYPTED_PACKET )
              {
                rc = decrypt_message( pmctl );

                if ( rc < 0 )  /* decryption error */
                  return rc;

                rcvd_cmd = pmb->hdr.cmd & ~GPS_CTRL_MSK;

                if ( rcvd_cmd == cmd )  /* the received packet is what we've been waiting for */
                  return TR_COMPLETE;
              }
            #endif

            /* not waiting  for a specific packet, so return if any packet is complete */
            if ( cmd == (uint16_t) -1 )
              return TR_COMPLETE;

            //##++ received a msg which does not match the expected code
            prctl->cnt = 0;      /* restart receiving */
          }
          break;

        default:    /* any error condition */
          return rc;

      }  /* switch */
    }
  }

}  // mbgextio_rcv_msg



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_xmt_cmd( MBG_MSG_CTL *pmctl, GPS_CMD cmd )
{
  int rc;

  #if _USE_MUTEX
    _mbg_mutex_acquire( &pmctl->xmt.xmt_mutex );
  #endif

  rc = xmt_cmd( pmctl, cmd );

  #if _USE_MUTEX
    _mbg_mutex_release( &pmctl->xmt.xmt_mutex );
  #endif

  return rc;

}  // mbgextio_xmt_cmd



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_xmt_cmd_us( MBG_MSG_CTL *pmctl, GPS_CMD cmd, uint16_t us )
{
  int rc;

  #if _USE_MUTEX
    _mbg_mutex_acquire( &pmctl->xmt.xmt_mutex );
  #endif

  rc = xmt_cmd_us( pmctl, cmd, us );

  #if _USE_MUTEX
    _mbg_mutex_release( &pmctl->xmt.xmt_mutex );
  #endif

  return rc;

}  // mbgextio_xmt_cmd_us



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_req_data( MBG_MSG_CTL *pmctl, GPS_CMD cmd )
{
  xmt_cmd( pmctl, cmd );   /* request a set of data */

  return mbgextio_rcv_msg( pmctl, cmd );

}  // mbgextio_req_data



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_req_data_idx( MBG_MSG_CTL *pmctl, GPS_CMD cmd, uint16_t idx )
{
  xmt_cmd_us( pmctl, cmd, idx );   /* request a set of data */

  return mbgextio_rcv_msg( pmctl, cmd );

}  // mbgextio_req_data_idx



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_receiver_info( MBG_MSG_CTL *pmctl, RECEIVER_INFO *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_RECEIVER_INFO );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.receiver_info;

  return rc;

}  // mbgextio_get_receiver_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_sw_rev( MBG_MSG_CTL *pmctl, SW_REV *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_SW_REV );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.sw_rev;

  return rc;

}  // mbgextio_get_sw_rev



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_bvar_stat( MBG_MSG_CTL *pmctl, BVAR_STAT *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_BVAR_STAT );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.bvar_stat;

  return rc;

}  // mbgextio_get_bvar_stat



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_time( MBG_MSG_CTL *pmctl, TTM *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_TIME );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.ttm;

  return rc;

}  // mbgextio_get_time



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_time( MBG_MSG_CTL *pmctl, const TTM *p )
{
  GPS_CMD cmd = GPS_TIME;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_time



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_pos_lla( MBG_MSG_CTL *pmctl, LLA lla )
{
  int rc = mbgextio_req_data( pmctl, GPS_POS_LLA );

  if ( rc == TR_COMPLETE )
  {
    MSG_DATA *pmb = &pmctl->rcv.pmb->u.msg_data;
    int i;

    for ( i = 0; i < N_LLA; i++ )
    {
      swap_double( &pmb->lla[i] );

      if ( lla )
        lla[i] = pmb->lla[i];
    }
  }

  return rc;

}  // mbgextio_get_pos_lla



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_pos_lla( MBG_MSG_CTL *pmctl, const LLA lla )
{
  GPS_CMD cmd = GPS_POS_LLA;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) lla, sizeof( LLA ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) lla, sizeof( LLA ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_pos_lla



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_tzdl( MBG_MSG_CTL *pmctl, TZDL *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_TZDL );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.tzdl;

  return rc;

}  // mbgextio_get_tzdl



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_tzdl( MBG_MSG_CTL *pmctl, const TZDL *p )
{
  GPS_CMD cmd = GPS_TZDL;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_get_tzdl



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_port_parm( MBG_MSG_CTL *pmctl, PORT_PARM *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_PORT_PARM );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.port_parm;

  return rc;

}  // mbgextio_get_port_parm



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_port_parm( MBG_MSG_CTL *pmctl, const PORT_PARM *p )
{
  GPS_CMD cmd = GPS_PORT_PARM;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else

  MBG_MSG_BUFF *pmb = pmctl->xmt.pmb;
  int rc;

  pmb->u.msg_data.port_parm = *p;

  pmb->hdr.len = sizeof( pmb->u.msg_data.port_parm );
  pmb->hdr.cmd = cmd | GPS_REQACK;
  xmt_tbuff( pmctl );

  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_port_parm



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_synth( MBG_MSG_CTL *pmctl, SYNTH *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_SYNTH );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.synth;

  return rc;

}  // mbgextio_get_synth



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_synth( MBG_MSG_CTL *pmctl, const SYNTH *p )
{
  GPS_CMD cmd = GPS_SYNTH;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_synth



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_ant_info( MBG_MSG_CTL *pmctl, ANT_INFO *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_ANT_INFO );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.ant_info;

  return rc;

}  // mbgextio_get_ant_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_ucap( MBG_MSG_CTL *pmctl, TTM *p )
{
  int rc;

  xmt_cmd( pmctl, GPS_UCAP );   /* request a set of data */

  // Attention: Older firmware versions may reply with GPS_TIME 
  // messages instead of GPS_UCAP messages, and may not send a reply 
  // at all if no capture event is available in the on-board FIFO.
  for (;;)
  {
    rc = mbgextio_rcv_msg( pmctl, -1 );

    if ( rc < 0 )
      break;

    if ( rc != TR_COMPLETE )
      continue;

    if ( pmctl->rcv.pmb->hdr.cmd == GPS_UCAP )
      break;

    if ( pmctl->rcv.pmb->hdr.cmd == GPS_TIME )
      if ( pmctl->rcv.pmb->hdr.len > 0 )
        if ( pmctl->rcv.pmb->u.msg_data.ttm.channel >= 0 )
          break;
  }

  if ( p )
  {
    // If the length of the msg header is 0 then the capture buffer
    // is empty. This is indicated with 0xFF in the seconds field of
    // the GPS time structure.
    if ( pmctl->rcv.pmb->hdr.len > 0 )
      *p = pmctl->rcv.pmb->u.msg_data.ttm;
    else
      _ttm_time_set_unavail( p );  // no capture event available
  }

  return rc;

}  // mbgextio_get_ucap



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_enable_flags( MBG_MSG_CTL *pmctl, ENABLE_FLAGS *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_ENABLE_FLAGS );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.enable_flags;

  return rc;

}  // mbgextio_get_enable_flags



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_enable_flags( MBG_MSG_CTL *pmctl, const ENABLE_FLAGS *p )
{
  GPS_CMD cmd = GPS_ENABLE_FLAGS;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_enable_flags



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_stat_info( MBG_MSG_CTL *pmctl, STAT_INFO *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_STAT_INFO );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.stat_info;

  return rc;

}  // mbgextio_get_stat_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_ant_cable_len( MBG_MSG_CTL *pmctl, ANT_CABLE_LEN *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_ANT_CABLE_LENGTH );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.ant_cable_len;

  return rc;

}  // mbgextio_get_ant_cable_len



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_ant_cable_len( MBG_MSG_CTL *pmctl, const ANT_CABLE_LEN *p )
{
  GPS_CMD cmd = GPS_ANT_CABLE_LENGTH;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_ant_cable_len



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_irig_tx_info( MBG_MSG_CTL *pmctl, IRIG_INFO *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_IRIG_TX_INFO );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.irig_tx_info;

  return rc;

}  // mbgextio_get_irig_tx_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_irig_tx_settings( MBG_MSG_CTL *pmctl, const IRIG_SETTINGS *p )
{
  GPS_CMD cmd = GPS_IRIG_TX_SETTINGS;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_irig_tx_settings



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_irig_rx_info( MBG_MSG_CTL *pmctl, IRIG_INFO *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_IRIG_RX_INFO );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.irig_rx_info;

  return rc;

}  // mbgextio_get_irig_rx_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_irig_rx_settings( MBG_MSG_CTL *pmctl, const IRIG_SETTINGS *p )
{
  GPS_CMD cmd = GPS_IRIG_RX_SETTINGS;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_irig_rx_settings



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_ref_offs( MBG_MSG_CTL *pmctl, MBG_REF_OFFS *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_REF_OFFS );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.ref_offs;

  return rc;

}  // mbgextio_get_ref_offs



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_ref_offs( MBG_MSG_CTL *pmctl, const MBG_REF_OFFS *p )
{
  GPS_CMD cmd = GPS_REF_OFFS;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_ref_offs



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_debug_status( MBG_MSG_CTL *pmctl, MBG_DEBUG_STATUS *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_DEBUG_STATUS );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.debug_status;

  return rc;

}  // mbgextio_get_debug_status



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_opt_info( MBG_MSG_CTL *pmctl, MBG_OPT_INFO *p )
{
  int rc = mbgextio_req_data( pmctl, GPS_OPT_INFO );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.opt_info;

  return rc;

}  // mbgextio_get_opt_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_opt_settings( MBG_MSG_CTL *pmctl, const MBG_OPT_SETTINGS *p )
{
  GPS_CMD cmd = GPS_OPT_SETTINGS;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else
  int rc;

  rc = mbgextio_xmt_msg( pmctl, (uint16_t) ( cmd | GPS_ACK ), (const uint8_t *) p, sizeof( *p ) );
  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_opt_settings



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_str_type_info_idx( MBG_MSG_CTL *pmctl,
                             STR_TYPE_INFO_IDX *p, uint16_t idx )
{
  int rc;

  xmt_cmd_us( pmctl, GPS_STR_TYPE_INFO_IDX, idx );

  rc = mbgextio_rcv_msg( pmctl, GPS_STR_TYPE_INFO_IDX );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.str_type_info_idx;

  return rc;

}  // mbgextio_get_str_type_info_idx



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_port_info_idx( MBG_MSG_CTL *pmctl, 
                             PORT_INFO_IDX *p, uint16_t idx )
{
  int rc;

  xmt_cmd_us( pmctl, GPS_PORT_INFO_IDX, idx );

  rc = mbgextio_rcv_msg( pmctl, GPS_PORT_INFO_IDX );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.port_info_idx;

  return rc;

}  // mbgextio_get_port_info_idx



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_port_settings_idx( MBG_MSG_CTL *pmctl,
                             const PORT_SETTINGS *p, uint16_t idx )
{
  GPS_CMD cmd = GPS_PORT_SETTINGS_IDX;
  MBG_MSG_BUFF *pmb = pmctl->xmt.pmb;
  int rc;

  pmb->u.msg_data.port_settings_idx.port_settings = *p;
  pmb->u.msg_data.port_settings_idx.idx = idx;

  pmb->hdr.len = sizeof( pmb->u.msg_data.port_settings_idx );
  pmb->hdr.cmd = cmd | GPS_REQACK;
  rc = xmt_tbuff( pmctl );

#if _MBGEXTIO_DIRECT_RC

  return rc;

#else

  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_port_settings_idx



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_pout_info_idx( MBG_MSG_CTL *pmctl, 
                             POUT_INFO_IDX *p, uint16_t idx )
{
  int rc;

  xmt_cmd_us( pmctl, GPS_POUT_INFO_IDX, idx );

  rc = mbgextio_rcv_msg( pmctl, GPS_POUT_INFO_IDX );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.pout_info_idx;

  return rc;

}  // mbgextio_get_pout_info_idx



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_pout_settings_idx( MBG_MSG_CTL *pmctl, 
                             const POUT_SETTINGS *p, uint16_t idx )
{
  GPS_CMD cmd = GPS_POUT_SETTINGS_IDX;
  MBG_MSG_BUFF *pmb = pmctl->xmt.pmb;
  int rc;

  pmb->u.msg_data.pout_settings_idx.pout_settings = *p;
  pmb->u.msg_data.pout_settings_idx.idx = idx;

  pmb->hdr.len = sizeof( pmb->u.msg_data.pout_settings_idx );
  pmb->hdr.cmd = cmd | GPS_REQACK;
  rc = xmt_tbuff( pmctl );

#if _MBGEXTIO_DIRECT_RC

  return rc;

#else

  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_pout_settings_idx



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_clr_ucap_buff( MBG_MSG_CTL *pmctl )
{
  return mbgextio_xmt_cmd( pmctl, GPS_CLR_UCAP_BUFF );

}  // mbgextio_clr_ucap_buff



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_get_time_scale_info( MBG_MSG_CTL *pmctl, 
                                                         MBG_TIME_SCALE_INFO *p )
{
  int rc;

  xmt_cmd( pmctl, GPS_TIME_SCALE );

  rc = mbgextio_rcv_msg( pmctl, GPS_TIME_SCALE );

  if ( ( rc == TR_COMPLETE ) && p )
    *p = pmctl->rcv.pmb->u.msg_data.time_scale_info;

  return rc;

}  // mbgextio_get_time_scale_info



/*HDR*/
_MBG_API_ATTR int _MBG_API mbgextio_set_time_scale_settings( MBG_MSG_CTL *pmctl, 
                             const MBG_TIME_SCALE_SETTINGS *p )
{
  GPS_CMD cmd = GPS_TIME_SCALE;

#if _MBGEXTIO_DIRECT_RC

  return mbgextio_xmt_msg( pmctl, cmd, (const uint8_t *) p, sizeof( *p ) );

#else

  MBG_MSG_BUFF *pmb = pmctl->xmt.pmb;
  int rc;

  pmb->u.msg_data.time_scale_settings = *p;

  pmb->hdr.len = sizeof( pmb->u.msg_data.time_scale_settings );
  pmb->hdr.cmd = cmd | GPS_REQACK;
  xmt_tbuff( pmctl );

  rc = mbgextio_rcv_msg( pmctl, cmd );

  if ( ( rc != TR_COMPLETE ) || !( pmctl->rcv.pmb->hdr.cmd & GPS_ACK ) ) 
  {
    return -1;  // no ack packet received
    // data has not been set or, if GPS_AUTO_ON has been 
    // transmitted before, an automatic frame (current time, capture)
    // has been sent before the acknowledge code.
  }

  return 0;

#endif

}  // mbgextio_set_time_scale_settings