aboutsummaryrefslogtreecommitdiff
path: root/Documentation/DocBook/media/dvb/frontend.xml
blob: 426c2526a4546a5fcf8ec27561d14482fa91593e (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
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
<title>DVB Frontend API</title>

<para>The DVB frontend device controls the tuner and DVB demodulator
hardware. It can be accessed through <emphasis
role="tt">/dev/dvb/adapter0/frontend0</emphasis>. Data types and and
ioctl definitions can be accessed by including <emphasis
role="tt">linux/dvb/frontend.h</emphasis> in your application.</para>

<para>DVB frontends come in three varieties: DVB-S (satellite), DVB-C
(cable) and DVB-T (terrestrial). Transmission via the internet (DVB-IP)
is not yet handled by this API but a future extension is possible. For
DVB-S the frontend device also supports satellite equipment control
(SEC) via DiSEqC and V-SEC protocols. The DiSEqC (digital SEC)
specification is available from
<ulink url="http://www.eutelsat.com/satellites/4_5_5.html">Eutelsat</ulink>.</para>

<para>Note that the DVB API may also be used for MPEG decoder-only PCI
cards, in which case there exists no frontend device.</para>

<section id="frontend_types">
<title>Frontend Data Types</title>

<section id="fe-type-t">
<title>Frontend type</title>

<para>For historical reasons, frontend types are named by the type of modulation used in
transmission. The fontend types are given by fe_type_t type, defined as:</para>

<table pgwide="1" frame="none" id="fe-type">
<title>Frontend types</title>
<tgroup cols="3">
   &cs-def;
   <thead>
     <row>
       <entry>fe_type</entry>
       <entry>Description</entry>
       <entry><link linkend="DTV-DELIVERY-SYSTEM">DTV_DELIVERY_SYSTEM</link> equivalent type</entry>
     </row>
  </thead>
  <tbody valign="top">
  <row>
     <entry id="FE_QPSK"><constant>FE_QPSK</constant></entry>
     <entry>For DVB-S standard</entry>
     <entry><constant>SYS_DVBS</constant></entry>
  </row>
  <row>
     <entry id="FE_QAM"><constant>FE_QAM</constant></entry>
     <entry>For DVB-C annex A standard</entry>
     <entry><constant>SYS_DVBC_ANNEX_A</constant></entry>
  </row>
  <row>
     <entry id="FE_OFDM"><constant>FE_OFDM</constant></entry>
     <entry>For DVB-T standard</entry>
     <entry><constant>SYS_DVBT</constant></entry>
  </row>
  <row>
     <entry id="FE_ATSC"><constant>FE_ATSC</constant></entry>
     <entry>For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used in US.</entry>
     <entry><constant>SYS_ATSC</constant> (terrestrial) or <constant>SYS_DVBC_ANNEX_B</constant> (cable)</entry>
  </row>
</tbody></tgroup></table>

<para>Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described at the above, as they're
supported via the new <link linkend="FE_GET_SET_PROPERTY">FE_GET_PROPERTY/FE_GET_SET_PROPERTY</link> ioctl's, using the <link linkend="DTV-DELIVERY-SYSTEM">DTV_DELIVERY_SYSTEM</link> parameter.
</para>

<para>The usage of this field is deprecated, as it doesn't report all supported standards, and
will provide an incomplete information for frontends that support multiple delivery systems.
Please use <link linkend="DTV-ENUM-DELSYS">DTV_ENUM_DELSYS</link> instead.</para>
</section>

<section id="fe-caps-t">
<title>frontend capabilities</title>

<para>Capabilities describe what a frontend can do. Some capabilities can only be supported for
a specific frontend type.</para>
<programlisting>
	typedef enum fe_caps {
	FE_IS_STUPID                  = 0,
	FE_CAN_INVERSION_AUTO         = 0x1,
	FE_CAN_FEC_1_2                = 0x2,
	FE_CAN_FEC_2_3                = 0x4,
	FE_CAN_FEC_3_4                = 0x8,
	FE_CAN_FEC_4_5                = 0x10,
	FE_CAN_FEC_5_6                = 0x20,
	FE_CAN_FEC_6_7                = 0x40,
	FE_CAN_FEC_7_8                = 0x80,
	FE_CAN_FEC_8_9                = 0x100,
	FE_CAN_FEC_AUTO               = 0x200,
	FE_CAN_QPSK                   = 0x400,
	FE_CAN_QAM_16                 = 0x800,
	FE_CAN_QAM_32                 = 0x1000,
	FE_CAN_QAM_64                 = 0x2000,
	FE_CAN_QAM_128                = 0x4000,
	FE_CAN_QAM_256                = 0x8000,
	FE_CAN_QAM_AUTO               = 0x10000,
	FE_CAN_TRANSMISSION_MODE_AUTO = 0x20000,
	FE_CAN_BANDWIDTH_AUTO         = 0x40000,
	FE_CAN_GUARD_INTERVAL_AUTO    = 0x80000,
	FE_CAN_HIERARCHY_AUTO         = 0x100000,
	FE_CAN_8VSB                   = 0x200000,
	FE_CAN_16VSB                  = 0x400000,
	FE_HAS_EXTENDED_CAPS          = 0x800000,
	FE_CAN_MULTISTREAM            = 0x4000000,
	FE_CAN_TURBO_FEC              = 0x8000000,
	FE_CAN_2G_MODULATION          = 0x10000000,
	FE_NEEDS_BENDING              = 0x20000000,
	FE_CAN_RECOVER                = 0x40000000,
	FE_CAN_MUTE_TS                = 0x80000000
	} fe_caps_t;
</programlisting>
</section>

<section id="dvb-frontend-info">
<title>frontend information</title>

<para>Information about the frontend ca be queried with
	<link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para>

<programlisting>
	struct dvb_frontend_info {
	char       name[128];
	fe_type_t  type;
	uint32_t   frequency_min;
	uint32_t   frequency_max;
	uint32_t   frequency_stepsize;
	uint32_t   frequency_tolerance;
	uint32_t   symbol_rate_min;
	uint32_t   symbol_rate_max;
	uint32_t   symbol_rate_tolerance;     /&#x22C6; ppm &#x22C6;/
	uint32_t   notifier_delay;            /&#x22C6; ms &#x22C6;/
	fe_caps_t  caps;
	};
</programlisting>
</section>

<section id="dvb-diseqc-master-cmd">
<title>diseqc master command</title>

<para>A message sent from the frontend to DiSEqC capable equipment.</para>
<programlisting>
	struct dvb_diseqc_master_cmd {
	uint8_t msg [6]; /&#x22C6;  { framing, address, command, data[3] } &#x22C6;/
	uint8_t msg_len; /&#x22C6;  valid values are 3...6  &#x22C6;/
	};
</programlisting>
</section>
<section role="subsection" id="dvb-diseqc-slave-reply">
<title>diseqc slave reply</title>

<para>A reply to the frontend from DiSEqC 2.0 capable equipment.</para>
<programlisting>
	struct dvb_diseqc_slave_reply {
	uint8_t msg [4]; /&#x22C6;  { framing, data [3] } &#x22C6;/
	uint8_t msg_len; /&#x22C6;  valid values are 0...4, 0 means no msg  &#x22C6;/
	int     timeout; /&#x22C6;  return from ioctl after timeout ms with &#x22C6;/
	};                       /&#x22C6;  errorcode when no message was received  &#x22C6;/
</programlisting>
</section>

<section id="fe-sec-voltage-t">
<title>diseqc slave reply</title>
<para>The voltage is usually used with non-DiSEqC capable LNBs to switch the polarzation
(horizontal/vertical). When using DiSEqC epuipment this voltage has to be switched
consistently to the DiSEqC commands as described in the DiSEqC spec.</para>
<programlisting>
	typedef enum fe_sec_voltage {
	SEC_VOLTAGE_13,
	SEC_VOLTAGE_18
	} fe_sec_voltage_t;
</programlisting>
</section>

<section id="fe-sec-tone-mode-t">
<title>SEC continuous tone</title>

<para>The continuous 22KHz tone is usually used with non-DiSEqC capable LNBs to switch the
high/low band of a dual-band LNB. When using DiSEqC epuipment this voltage has to
be switched consistently to the DiSEqC commands as described in the DiSEqC
spec.</para>
<programlisting>
	typedef enum fe_sec_tone_mode {
	SEC_TONE_ON,
	SEC_TONE_OFF
	} fe_sec_tone_mode_t;
</programlisting>
</section>

<section id="fe-sec-mini-cmd-t">
<title>SEC tone burst</title>

<para>The 22KHz tone burst is usually used with non-DiSEqC capable switches to select
between two connected LNBs/satellites. When using DiSEqC epuipment this voltage has to
be switched consistently to the DiSEqC commands as described in the DiSEqC
spec.</para>
<programlisting>
	typedef enum fe_sec_mini_cmd {
	SEC_MINI_A,
	SEC_MINI_B
	} fe_sec_mini_cmd_t;
</programlisting>

<para></para>
</section>

<section id="fe-status-t">
<title>frontend status</title>
<para>Several functions of the frontend device use the fe_status data type defined
by</para>
<programlisting>
typedef enum fe_status {
	FE_HAS_SIGNAL		= 0x01,
	FE_HAS_CARRIER		= 0x02,
	FE_HAS_VITERBI		= 0x04,
	FE_HAS_SYNC		= 0x08,
	FE_HAS_LOCK		= 0x10,
	FE_TIMEDOUT		= 0x20,
	FE_REINIT		= 0x40,
} fe_status_t;
</programlisting>
<para>to indicate the current state and/or state changes of the frontend hardware:
</para>

<informaltable><tgroup cols="2"><tbody>
<row>
<entry align="char">FE_HAS_SIGNAL</entry>
<entry align="char">The frontend has found something above the noise level</entry>
</row><row>
<entry align="char">FE_HAS_CARRIER</entry>
<entry align="char">The frontend has found a DVB signal</entry>
</row><row>
<entry align="char">FE_HAS_VITERBI</entry>
<entry align="char">The frontend FEC code is stable</entry>
</row><row>
<entry align="char">FE_HAS_SYNC</entry>
<entry align="char">Syncronization bytes was found</entry>
</row><row>
<entry align="char">FE_HAS_LOCK</entry>
<entry align="char">The DVB were locked and everything is working</entry>
</row><row>
<entry align="char">FE_TIMEDOUT</entry>
<entry align="char">no lock within the last about 2 seconds</entry>
</row><row>
<entry align="char">FE_REINIT</entry>
<entry align="char">The frontend was reinitialized, application is
recommended to reset DiSEqC, tone and parameters</entry>
</row>
</tbody></tgroup></informaltable>

</section>

<section id="dvb-frontend-parameters">
<title>frontend parameters</title>
<para>The kind of parameters passed to the frontend device for tuning depend on
the kind of hardware you are using.</para>
<para>The struct <constant>dvb_frontend_parameters</constant> uses an
union with specific per-system parameters. However, as newer delivery systems
required more data, the structure size weren't enough to fit, and just
extending its size would break the existing applications. So, those parameters
were replaced by the usage of <link linkend="FE_GET_SET_PROPERTY">
<constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant></link> ioctl's. The
new API is flexible enough to add new parameters to existing delivery systems,
and to add newer delivery systems.</para>
<para>So, newer applications should use <link linkend="FE_GET_SET_PROPERTY">
<constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant></link> instead, in
order to be able to support the newer System Delivery like  DVB-S2, DVB-T2,
DVB-C2, ISDB, etc.</para>
<para>All kinds of parameters are combined as an union in the FrontendParameters structure:
<programlisting>
struct dvb_frontend_parameters {
	uint32_t frequency;     /&#x22C6; (absolute) frequency in Hz for QAM/OFDM &#x22C6;/
				/&#x22C6; intermediate frequency in kHz for QPSK &#x22C6;/
	fe_spectral_inversion_t inversion;
	union {
		struct dvb_qpsk_parameters qpsk;
		struct dvb_qam_parameters  qam;
		struct dvb_ofdm_parameters ofdm;
		struct dvb_vsb_parameters  vsb;
	} u;
};
</programlisting></para>
<para>In the case of QPSK frontends the <constant>frequency</constant> field specifies the intermediate
frequency, i.e. the offset which is effectively added to the local oscillator frequency (LOF) of
the LNB. The intermediate frequency has to be specified in units of kHz. For QAM and
OFDM frontends the <constant>frequency</constant> specifies the absolute frequency and is given in Hz.
</para>

<section id="dvb-qpsk-parameters">
<title>QPSK parameters</title>
<para>For satellite QPSK frontends you have to use the <constant>dvb_qpsk_parameters</constant> structure:</para>
<programlisting>
 struct dvb_qpsk_parameters {
	 uint32_t        symbol_rate;  /&#x22C6; symbol rate in Symbols per second &#x22C6;/
	 fe_code_rate_t  fec_inner;    /&#x22C6; forward error correction (see above) &#x22C6;/
 };
</programlisting>
</section>
<section id="dvb-qam-parameters">
<title>QAM parameters</title>
<para>for cable QAM frontend you use the <constant>dvb_qam_parameters</constant> structure:</para>
<programlisting>
 struct dvb_qam_parameters {
	 uint32_t         symbol_rate; /&#x22C6; symbol rate in Symbols per second &#x22C6;/
	 fe_code_rate_t   fec_inner;   /&#x22C6; forward error correction (see above) &#x22C6;/
	 fe_modulation_t  modulation;  /&#x22C6; modulation type (see above) &#x22C6;/
 };
</programlisting>
</section>
<section id="dvb-vsb-parameters">
<title>VSB parameters</title>
<para>ATSC frontends are supported by the <constant>dvb_vsb_parameters</constant> structure:</para>
<programlisting>
struct dvb_vsb_parameters {
	fe_modulation_t modulation;	/&#x22C6; modulation type (see above) &#x22C6;/
};
</programlisting>
</section>
<section id="dvb-ofdm-parameters">
<title>OFDM parameters</title>
<para>DVB-T frontends are supported by the <constant>dvb_ofdm_parameters</constant> structure:</para>
<programlisting>
 struct dvb_ofdm_parameters {
	 fe_bandwidth_t      bandwidth;
	 fe_code_rate_t      code_rate_HP;  /&#x22C6; high priority stream code rate &#x22C6;/
	 fe_code_rate_t      code_rate_LP;  /&#x22C6; low priority stream code rate &#x22C6;/
	 fe_modulation_t     constellation; /&#x22C6; modulation type (see above) &#x22C6;/
	 fe_transmit_mode_t  transmission_mode;
	 fe_guard_interval_t guard_interval;
	 fe_hierarchy_t      hierarchy_information;
 };
</programlisting>
</section>
<section id="fe-spectral-inversion-t">
<title>frontend spectral inversion</title>
<para>The Inversion field can take one of these values:
</para>
<programlisting>
typedef enum fe_spectral_inversion {
	INVERSION_OFF,
	INVERSION_ON,
	INVERSION_AUTO
} fe_spectral_inversion_t;
</programlisting>
<para>It indicates if spectral inversion should be presumed or not. In the automatic setting
(<constant>INVERSION_AUTO</constant>) the hardware will try to figure out the correct setting by
itself.
</para>
</section>
<section id="fe-code-rate-t">
<title>frontend code rate</title>
<para>The possible values for the <constant>fec_inner</constant> field used on
<link linkend="dvb-qpsk-parameters"><constant>struct dvb_qpsk_parameters</constant></link> and
<link linkend="dvb-qam-parameters"><constant>struct dvb_qam_parameters</constant></link> are:
</para>
<programlisting>
typedef enum fe_code_rate {
	FEC_NONE = 0,
	FEC_1_2,
	FEC_2_3,
	FEC_3_4,
	FEC_4_5,
	FEC_5_6,
	FEC_6_7,
	FEC_7_8,
	FEC_8_9,
	FEC_AUTO,
	FEC_3_5,
	FEC_9_10,
} fe_code_rate_t;
</programlisting>
<para>which correspond to error correction rates of 1/2, 2/3, etc., no error correction or auto
detection.
</para>
</section>
<section id="fe-modulation-t">
<title>frontend modulation type for QAM, OFDM and VSB</title>
<para>For cable and terrestrial frontends, e. g. for
<link linkend="dvb-qam-parameters"><constant>struct dvb_qpsk_parameters</constant></link>,
<link linkend="dvb-ofdm-parameters"><constant>struct dvb_qam_parameters</constant></link> and
<link linkend="dvb-vsb-parameters"><constant>struct dvb_qam_parameters</constant></link>,
it needs to specify the quadrature modulation mode which can be one of the following:
</para>
<programlisting>
 typedef enum fe_modulation {
	QPSK,
	QAM_16,
	QAM_32,
	QAM_64,
	QAM_128,
	QAM_256,
	QAM_AUTO,
	VSB_8,
	VSB_16,
	PSK_8,
	APSK_16,
	APSK_32,
	DQPSK,
 } fe_modulation_t;
</programlisting>
</section>
<section>
<title>More OFDM parameters</title>
<section id="fe-transmit-mode-t">
<title>Number of carriers per channel</title>
<programlisting>
typedef enum fe_transmit_mode {
	TRANSMISSION_MODE_2K,
	TRANSMISSION_MODE_8K,
	TRANSMISSION_MODE_AUTO,
	TRANSMISSION_MODE_4K,
	TRANSMISSION_MODE_1K,
	TRANSMISSION_MODE_16K,
	TRANSMISSION_MODE_32K,
 } fe_transmit_mode_t;
</programlisting>
</section>
<section id="fe-bandwidth-t">
<title>frontend bandwidth</title>
<programlisting>
typedef enum fe_bandwidth {
	BANDWIDTH_8_MHZ,
	BANDWIDTH_7_MHZ,
	BANDWIDTH_6_MHZ,
	BANDWIDTH_AUTO,
	BANDWIDTH_5_MHZ,
	BANDWIDTH_10_MHZ,
	BANDWIDTH_1_712_MHZ,
} fe_bandwidth_t;
</programlisting>
</section>
<section id="fe-guard-interval-t">
<title>frontend guard inverval</title>
<programlisting>
typedef enum fe_guard_interval {
	GUARD_INTERVAL_1_32,
	GUARD_INTERVAL_1_16,
	GUARD_INTERVAL_1_8,
	GUARD_INTERVAL_1_4,
	GUARD_INTERVAL_AUTO,
	GUARD_INTERVAL_1_128,
	GUARD_INTERVAL_19_128,
	GUARD_INTERVAL_19_256,
} fe_guard_interval_t;
</programlisting>
</section>
<section id="fe-hierarchy-t">
<title>frontend hierarchy</title>
<programlisting>
typedef enum fe_hierarchy {
	 HIERARCHY_NONE,
	 HIERARCHY_1,
	 HIERARCHY_2,
	 HIERARCHY_4,
	 HIERARCHY_AUTO
 } fe_hierarchy_t;
</programlisting>
</section>
</section>

</section>

<section id="dvb-frontend-event">
<title>frontend events</title>
 <programlisting>
 struct dvb_frontend_event {
	 fe_status_t status;
	 struct dvb_frontend_parameters parameters;
 };
</programlisting>
 </section>
</section>


<section id="frontend_fcalls">
<title>Frontend Function Calls</title>

<section id="frontend_f_open">
<title>open()</title>
<para>DESCRIPTION</para>
<informaltable><tgroup cols="1"><tbody><row>
<entry align="char">
<para>This system call opens a named frontend device (/dev/dvb/adapter0/frontend0)
 for subsequent use. Usually the first thing to do after a successful open is to
 find out the frontend type with <link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para>
<para>The device can be opened in read-only mode, which only allows monitoring of
 device status and statistics, or read/write mode, which allows any kind of use
 (e.g. performing tuning operations.)
</para>
<para>In a system with multiple front-ends, it is usually the case that multiple devices
 cannot be open in read/write mode simultaneously. As long as a front-end
 device is opened in read/write mode, other open() calls in read/write mode will
 either fail or block, depending on whether non-blocking or blocking mode was
 specified. A front-end device opened in blocking mode can later be put into
 non-blocking mode (and vice versa) using the F_SETFL command of the fcntl
 system call. This is a standard system call, documented in the Linux manual
 page for fcntl. When an open() call has succeeded, the device will be ready
 for use in the specified mode. This implies that the corresponding hardware is
 powered up, and that other front-ends may have been powered down to make
 that possible.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int open(const char &#x22C6;deviceName, int flags);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>const char
 *deviceName</para>
</entry><entry
 align="char">
<para>Name of specific video device.</para>
</entry>
 </row><row><entry
 align="char">
<para>int flags</para>
</entry><entry
 align="char">
<para>A bit-wise OR of the following flags:</para>
</entry>
 </row><row><entry
 align="char">
</entry><entry
 align="char">
<para>O_RDONLY read-only access</para>
</entry>
 </row><row><entry
 align="char">
</entry><entry
 align="char">
<para>O_RDWR read/write access</para>
</entry>
 </row><row><entry
 align="char">
</entry><entry
 align="char">
<para>O_NONBLOCK open in non-blocking mode</para>
</entry>
 </row><row><entry
 align="char">
</entry><entry
 align="char">
<para>(blocking mode is the default)</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>RETURN VALUE</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>ENODEV</para>
</entry><entry
 align="char">
<para>Device driver not loaded/available.</para>
</entry>
 </row><row><entry
 align="char">
<para>EINTERNAL</para>
</entry><entry
 align="char">
<para>Internal error.</para>
</entry>
 </row><row><entry
 align="char">
<para>EBUSY</para>
</entry><entry
 align="char">
<para>Device or resource busy.</para>
</entry>
 </row><row><entry
 align="char">
<para>EINVAL</para>
</entry><entry
 align="char">
<para>Invalid argument.</para>
</entry>
 </row></tbody></tgroup></informaltable>
</section>

<section id="frontend_f_close">
<title>close()</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This system call closes a previously opened front-end device. After closing
 a front-end device, its corresponding hardware might be powered down
 automatically.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int close(int fd);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>RETURN VALUE</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>EBADF</para>
</entry><entry
 align="char">
<para>fd is not a valid open file descriptor.</para>
</entry>
 </row></tbody></tgroup></informaltable>
</section>

<section id="FE_READ_STATUS">
<title>FE_READ_STATUS</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns status information about the front-end. This call only
 requires read-only access to the device.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_READ_STATUS">FE_READ_STATUS</link>,
 fe_status_t &#x22C6;status);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>

<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_READ_STATUS">FE_READ_STATUS</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct fe_status_t
 *status</para>
</entry><entry
 align="char">
<para>Points to the location where the front-end status word is
 to be stored.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>RETURN VALUE</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>EBADF</para>
</entry><entry
 align="char">
<para>fd is not a valid open file descriptor.</para>
</entry>
 </row><row><entry
 align="char">
<para>EFAULT</para>
</entry><entry
 align="char">
<para>status points to invalid address.</para>
</entry>
 </row></tbody></tgroup></informaltable>
</section>

<section id="FE_READ_BER">
<title>FE_READ_BER</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns the bit error rate for the signal currently
 received/demodulated by the front-end. For this command, read-only access to
 the device is sufficient.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_READ_BER">FE_READ_BER</link>,
 uint32_t &#x22C6;ber);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_READ_BER">FE_READ_BER</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>uint32_t *ber</para>
</entry><entry
 align="char">
<para>The bit error rate is stored into *ber.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_READ_SNR">
<title>FE_READ_SNR</title>

<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns the signal-to-noise ratio for the signal currently received
 by the front-end. For this command, read-only access to the device is sufficient.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_READ_SNR">FE_READ_SNR</link>, int16_t
 &#x22C6;snr);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_READ_SNR">FE_READ_SNR</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>int16_t *snr</para>
</entry><entry
 align="char">
<para>The signal-to-noise ratio is stored into *snr.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_READ_SIGNAL_STRENGTH">
<title>FE_READ_SIGNAL_STRENGTH</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns the signal strength value for the signal currently received
 by the front-end. For this command, read-only access to the device is sufficient.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl( int fd, int request =
 <link linkend="FE_READ_SIGNAL_STRENGTH">FE_READ_SIGNAL_STRENGTH</link>, int16_t &#x22C6;strength);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_READ_SIGNAL_STRENGTH">FE_READ_SIGNAL_STRENGTH</link> for this
 command.</para>
</entry>
 </row><row><entry
 align="char">
<para>int16_t *strength</para>
</entry><entry
 align="char">
<para>The signal strength value is stored into *strength.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_READ_UNCORRECTED_BLOCKS">
<title>FE_READ_UNCORRECTED_BLOCKS</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns the number of uncorrected blocks detected by the device
 driver during its lifetime. For meaningful measurements, the increment in block
 count during a specific time interval should be calculated. For this command,
 read-only access to the device is sufficient.</para>
</entry>
 </row><row><entry
 align="char">
<para>Note that the counter will wrap to zero after its maximum count has been
 reached.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl( int fd, int request =
 <link linkend="FE_READ_UNCORRECTED_BLOCKS">FE_READ_UNCORRECTED_BLOCKS</link>, uint32_t &#x22C6;ublocks);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_READ_UNCORRECTED_BLOCKS">FE_READ_UNCORRECTED_BLOCKS</link> for this
 command.</para>
</entry>
 </row><row><entry
 align="char">
<para>uint32_t *ublocks</para>
</entry><entry
 align="char">
<para>The total number of uncorrected blocks seen by the driver
 so far.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_SET_FRONTEND">
<title>FE_SET_FRONTEND</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call starts a tuning operation using specified parameters. The result
 of this call will be successful if the parameters were valid and the tuning could
 be initiated. The result of the tuning operation in itself, however, will arrive
 asynchronously as an event (see documentation for <link linkend="FE_GET_EVENT">FE_GET_EVENT</link> and
 FrontendEvent.) If a new <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> operation is initiated before
 the previous one was completed, the previous operation will be aborted in favor
 of the new one. This command requires read/write access to the device.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link>,
 struct dvb_frontend_parameters &#x22C6;p);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct
 dvb_frontend_parameters
 *p</para>
</entry><entry
 align="char">
<para>Points to parameters for tuning operation.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>EINVAL</para>
</entry><entry
 align="char">
<para>Maximum supported symbol rate reached.</para>
</entry>
</row></tbody></tgroup></informaltable>
</section>

<section id="FE_GET_FRONTEND">
<title>FE_GET_FRONTEND</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call queries the currently effective frontend parameters. For this
 command, read-only access to the device is sufficient.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_GET_FRONTEND">FE_GET_FRONTEND</link>,
 struct dvb_frontend_parameters &#x22C6;p);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct
 dvb_frontend_parameters
 *p</para>
</entry><entry
 align="char">
<para>Points to parameters for tuning operation.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>EINVAL</para>
</entry><entry
 align="char">
<para>Maximum supported symbol rate reached.</para>
</entry>
 </row></tbody></tgroup></informaltable>

</section>

<section id="FE_GET_EVENT">
<title>FE_GET_EVENT</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns a frontend event if available. If an event is not
 available, the behavior depends on whether the device is in blocking or
 non-blocking mode. In the latter case, the call fails immediately with errno
 set to EWOULDBLOCK. In the former case, the call blocks until an event
 becomes available.</para>
</entry>
 </row><row><entry
 align="char">
<para>The standard Linux poll() and/or select() system calls can be used with the
 device file descriptor to watch for new events. For select(), the file descriptor
 should be included in the exceptfds argument, and for poll(), POLLPRI should
 be specified as the wake-up condition. Since the event queue allocated is
 rather small (room for 8 events), the queue must be serviced regularly to avoid
 overflow. If an overflow happens, the oldest event is discarded from the queue,
 and an error (EOVERFLOW) occurs the next time the queue is read. After
 reporting the error condition in this fashion, subsequent
 <link linkend="FE_GET_EVENT">FE_GET_EVENT</link>
 calls will return events from the queue as usual.</para>
</entry>
 </row><row><entry
 align="char">
<para>For the sake of implementation simplicity, this command requires read/write
 access to the device.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = QPSK_GET_EVENT,
 struct dvb_frontend_event &#x22C6;ev);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_GET_EVENT">FE_GET_EVENT</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct
 dvb_frontend_event
 *ev</para>
</entry><entry
 align="char">
<para>Points to the location where the event,</para>
</entry>
 </row><row><entry
 align="char">
</entry><entry
 align="char">
<para>if any, is to be stored.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>EWOULDBLOCK</para>
</entry><entry
 align="char">
<para>There is no event pending, and the device is in
 non-blocking mode.</para>
</entry>
 </row><row><entry
 align="char">
<para>EOVERFLOW</para>
</entry><entry
 align="char">
<para>Overflow in event queue - one or more events were lost.</para>
</entry>
</row></tbody></tgroup></informaltable>
</section>

<section id="FE_GET_INFO">
<title>FE_GET_INFO</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call returns information about the front-end. This call only requires
 read-only access to the device.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>

<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para> int ioctl(int fd, int request = <link linkend="FE_GET_INFO">FE_GET_INFO</link>, struct
 dvb_frontend_info &#x22C6;info);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>

<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_GET_INFO">FE_GET_INFO</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct
 dvb_frontend_info
 *info</para>
</entry><entry
 align="char">
<para>Points to the location where the front-end information is
 to be stored.</para>
</entry>
 </row></tbody></tgroup></informaltable>
&return-value-dvb;
</section>

<section id="FE_DISEQC_RESET_OVERLOAD">
<title>FE_DISEQC_RESET_OVERLOAD</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>If the bus has been automatically powered off due to power overload, this ioctl
 call restores the power to the bus. The call requires read/write access to the
 device. This call has no effect if the device is manually powered off. Not all
 DVB adapters support this ioctl.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request =
 <link linkend="FE_DISEQC_RESET_OVERLOAD">FE_DISEQC_RESET_OVERLOAD</link>);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_DISEQC_RESET_OVERLOAD">FE_DISEQC_RESET_OVERLOAD</link> for this
 command.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_DISEQC_SEND_MASTER_CMD">
<title>FE_DISEQC_SEND_MASTER_CMD</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call is used to send a a DiSEqC command.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request =
 <link linkend="FE_DISEQC_SEND_MASTER_CMD">FE_DISEQC_SEND_MASTER_CMD</link>, struct
 dvb_diseqc_master_cmd &#x22C6;cmd);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_DISEQC_SEND_MASTER_CMD">FE_DISEQC_SEND_MASTER_CMD</link> for this
 command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct
 dvb_diseqc_master_cmd
 *cmd</para>
</entry><entry
 align="char">
<para>Pointer to the command to be transmitted.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_DISEQC_RECV_SLAVE_REPLY">
<title>FE_DISEQC_RECV_SLAVE_REPLY</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call is used to receive reply to a DiSEqC 2.0 command.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request =
 <link linkend="FE_DISEQC_RECV_SLAVE_REPLY">FE_DISEQC_RECV_SLAVE_REPLY</link>, struct
 dvb_diseqc_slave_reply &#x22C6;reply);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_DISEQC_RECV_SLAVE_REPLY">FE_DISEQC_RECV_SLAVE_REPLY</link> for this
 command.</para>
</entry>
 </row><row><entry
 align="char">
<para>struct
 dvb_diseqc_slave_reply
 *reply</para>
</entry><entry
 align="char">
<para>Pointer to the command to be received.</para>
</entry>
 </row></tbody></tgroup></informaltable>
&return-value-dvb;
</section>

<section id="FE_DISEQC_SEND_BURST">
<title>FE_DISEQC_SEND_BURST</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This ioctl call is used to send a 22KHz tone burst.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request =
 <link linkend="FE_DISEQC_SEND_BURST">FE_DISEQC_SEND_BURST</link>, fe_sec_mini_cmd_t burst);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_DISEQC_SEND_BURST">FE_DISEQC_SEND_BURST</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>fe_sec_mini_cmd_t
 burst</para>
</entry><entry
 align="char">
<para>burst A or B.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_SET_TONE">
<title>FE_SET_TONE</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This call is used to set the generation of the continuous 22kHz tone. This call
 requires read/write permissions.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_SET_TONE">FE_SET_TONE</link>,
 fe_sec_tone_mode_t tone);</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_SET_TONE">FE_SET_TONE</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>fe_sec_tone_mode_t
 tone</para>
</entry><entry
 align="char">
<para>The requested tone generation mode (on/off).</para>
</entry>
 </row></tbody></tgroup></informaltable>
&return-value-dvb;
</section>

<section id="FE_SET_VOLTAGE">
<title>FE_SET_VOLTAGE</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>This call is used to set the bus voltage. This call requires read/write
 permissions.</para>
</entry>
 </row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link>,
 fe_sec_voltage_t voltage);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>fe_sec_voltage_t
 voltage</para>
</entry><entry
 align="char">
<para>The requested bus voltage.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_ENABLE_HIGH_LNB_VOLTAGE">
<title>FE_ENABLE_HIGH_LNB_VOLTAGE</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>If high != 0 enables slightly higher voltages instead of 13/18V (to compensate
 for long cables). This call requires read/write permissions. Not all DVB
 adapters support this ioctl.</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
 align="char">
<para>int ioctl(int fd, int request =
 <link linkend="FE_ENABLE_HIGH_LNB_VOLTAGE">FE_ENABLE_HIGH_LNB_VOLTAGE</link>, int high);</para>
</entry>
 </row></tbody></tgroup></informaltable>

<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
 align="char">
<para>int fd</para>
</entry><entry
 align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
 </row><row><entry
 align="char">
<para>int request</para>
</entry><entry
 align="char">
<para>Equals <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link> for this command.</para>
</entry>
 </row><row><entry
 align="char">
<para>int high</para>
</entry><entry
 align="char">
<para>The requested bus voltage.</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_SET_FRONTEND_TUNE_MODE">
<title>FE_SET_FRONTEND_TUNE_MODE</title>
<para>DESCRIPTION</para>
<informaltable><tgroup cols="1"><tbody><row>
<entry align="char">
<para>Allow setting tuner mode flags to the frontend.</para>
</entry>
</row></tbody></tgroup></informaltable>

<para>SYNOPSIS</para>
<informaltable><tgroup cols="1"><tbody><row>
<entry align="char">
<para>int ioctl(int fd, int request =
<link linkend="FE_SET_FRONTEND_TUNE_MODE">FE_SET_FRONTEND_TUNE_MODE</link>, unsigned int flags);</para>
</entry>
</row></tbody></tgroup></informaltable>

<para>PARAMETERS</para>
<informaltable><tgroup cols="2"><tbody><row>
<entry align="char">
	<para>unsigned int flags</para>
</entry>
<entry align="char">
<para>
FE_TUNE_MODE_ONESHOT When set, this flag will disable any zigzagging or other "normal" tuning behaviour. Additionally, there will be no automatic monitoring of the lock status, and hence no frontend events will be generated. If a frontend device is closed, this flag will be automatically turned off when the device is reopened read-write.
</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

<section id="FE_DISHNETWORK_SEND_LEGACY_CMD">
	<title>FE_DISHNETWORK_SEND_LEGACY_CMD</title>
<para>DESCRIPTION</para>
<informaltable><tgroup cols="1"><tbody><row>
<entry align="char">
<para>WARNING: This is a very obscure legacy command, used only at stv0299 driver. Should not be used on newer drivers.</para>
<para>It provides a non-standard method for selecting Diseqc voltage on the frontend, for Dish Network legacy switches.</para>
<para>As support for this ioctl were added in 2004, this means that such dishes were already legacy in 2004.</para>
</entry>
</row></tbody></tgroup></informaltable>

<para>SYNOPSIS</para>
<informaltable><tgroup cols="1"><tbody><row>
<entry align="char">
<para>int ioctl(int fd, int request =
	<link linkend="FE_DISHNETWORK_SEND_LEGACY_CMD">FE_DISHNETWORK_SEND_LEGACY_CMD</link>, unsigned long cmd);</para>
</entry>
</row></tbody></tgroup></informaltable>

<para>PARAMETERS</para>
<informaltable><tgroup cols="2"><tbody><row>
<entry align="char">
	<para>unsigned long cmd</para>
</entry>
<entry align="char">
<para>
sends the specified raw cmd to the dish via DISEqC.
</para>
</entry>
 </row></tbody></tgroup></informaltable>

&return-value-dvb;
</section>

</section>

&sub-dvbproperty;