1.. Permission is granted to copy, distribute and/or modify this 2.. document under the terms of the GNU Free Documentation License, 3.. Version 1.1 or any later version published by the Free Software 4.. Foundation, with no Invariant Sections, no Front-Cover Texts 5.. and no Back-Cover Texts. A copy of the license is included at 6.. Documentation/userspace-api/media/fdl-appendix.rst. 7.. 8.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections 9 10.. _fe_property_parameters: 11 12****************************** 13Digital TV property parameters 14****************************** 15 16There are several different Digital TV parameters that can be used by 17:ref:`FE_SET_PROPERTY and FE_GET_PROPERTY ioctls<FE_GET_PROPERTY>`. 18This section describes each of them. Please notice, however, that only 19a subset of them are needed to setup a frontend. 20 21 22.. _DTV-UNDEFINED: 23 24DTV_UNDEFINED 25============= 26 27Used internally. A GET/SET operation for it won't change or return 28anything. 29 30 31.. _DTV-TUNE: 32 33DTV_TUNE 34======== 35 36Interpret the cache of data, build either a traditional frontend 37tunerequest so we can pass validation in the ``FE_SET_FRONTEND`` ioctl. 38 39 40.. _DTV-CLEAR: 41 42DTV_CLEAR 43========= 44 45Reset a cache of data specific to the frontend here. This does not 46effect hardware. 47 48 49.. _DTV-FREQUENCY: 50 51DTV_FREQUENCY 52============= 53 54Frequency of the digital TV transponder/channel. 55 56.. note:: 57 58 #. For satellite delivery systems, the frequency is in kHz. 59 60 #. For cable and terrestrial delivery systems, the frequency is in 61 Hz. 62 63 #. On most delivery systems, the frequency is the center frequency 64 of the transponder/channel. The exception is for ISDB-T, where 65 the main carrier has a 1/7 offset from the center. 66 67 #. For ISDB-T, the channels are usually transmitted with an offset of 68 about 143kHz. E.g. a valid frequency could be 474,143 kHz. The 69 stepping is bound to the bandwidth of the channel which is 70 typically 6MHz. 71 72 #. In ISDB-Tsb, the channel consists of only one or three segments the 73 frequency step is 429kHz, 3*429 respectively. 74 75 76.. _DTV-MODULATION: 77 78DTV_MODULATION 79============== 80 81Specifies the frontend modulation type for delivery systems that 82supports more multiple modulations. 83 84The modulation can be one of the types defined by enum :c:type:`fe_modulation`. 85 86Most of the digital TV standards offers more than one possible 87modulation type. 88 89The table below presents a summary of the types of modulation types 90supported by each delivery system, as currently defined by specs. 91 92======================= ======================================================= 93Standard Modulation types 94======================= ======================================================= 95ATSC (version 1) 8-VSB and 16-VSB. 96DMTB 4-QAM, 16-QAM, 32-QAM, 64-QAM and 4-QAM-NR. 97DVB-C Annex A/C 16-QAM, 32-QAM, 64-QAM and 256-QAM. 98DVB-C Annex B 64-QAM. 99DVB-T QPSK, 16-QAM and 64-QAM. 100DVB-T2 QPSK, 16-QAM, 64-QAM and 256-QAM. 101DVB-S No need to set. It supports only QPSK. 102DVB-S2 QPSK, 8-PSK, 16-APSK and 32-APSK. 103ISDB-T QPSK, DQPSK, 16-QAM and 64-QAM. 104ISDB-S 8-PSK, QPSK and BPSK. 105======================= ======================================================= 106 107.. note:: 108 109 Please notice that some of the above modulation types may not be 110 defined currently at the Kernel. The reason is simple: no driver 111 needed such definition yet. 112 113 114.. _DTV-BANDWIDTH-HZ: 115 116DTV_BANDWIDTH_HZ 117================ 118 119Bandwidth for the channel, in HZ. 120 121Should be set only for terrestrial delivery systems. 122 123Possible values: ``1712000``, ``5000000``, ``6000000``, ``7000000``, 124``8000000``, ``10000000``. 125 126======================= ======================================================= 127Terrestrial Standard Possible values for bandwidth 128======================= ======================================================= 129ATSC (version 1) No need to set. It is always 6MHz. 130DMTB No need to set. It is always 8MHz. 131DVB-T 6MHz, 7MHz and 8MHz. 132DVB-T2 1.172 MHz, 5MHz, 6MHz, 7MHz, 8MHz and 10MHz 133ISDB-T 5MHz, 6MHz, 7MHz and 8MHz, although most places 134 use 6MHz. 135======================= ======================================================= 136 137 138.. note:: 139 140 141 #. For ISDB-Tsb, the bandwidth can vary depending on the number of 142 connected segments. 143 144 It can be easily derived from other parameters 145 (DTV_ISDBT_SB_SEGMENT_IDX, DTV_ISDBT_SB_SEGMENT_COUNT). 146 147 #. On Satellite and Cable delivery systems, the bandwidth depends on 148 the symbol rate. So, the Kernel will silently ignore any setting 149 :ref:`DTV-BANDWIDTH-HZ`. I will however fill it back with a 150 bandwidth estimation. 151 152 Such bandwidth estimation takes into account the symbol rate set with 153 :ref:`DTV-SYMBOL-RATE`, and the rolloff factor, with is fixed for 154 DVB-C and DVB-S. 155 156 For DVB-S2, the rolloff should also be set via :ref:`DTV-ROLLOFF`. 157 158 159.. _DTV-INVERSION: 160 161DTV_INVERSION 162============= 163 164Specifies if the frontend should do spectral inversion or not. 165 166The acceptable values are defined by :c:type:`fe_spectral_inversion`. 167 168 169.. _DTV-DISEQC-MASTER: 170 171DTV_DISEQC_MASTER 172================= 173 174Currently not implemented. 175 176 177.. _DTV-SYMBOL-RATE: 178 179DTV_SYMBOL_RATE 180=============== 181 182Used on cable and satellite delivery systems. 183 184Digital TV symbol rate, in bauds (symbols/second). 185 186 187.. _DTV-INNER-FEC: 188 189DTV_INNER_FEC 190============= 191 192Used on cable and satellite delivery systems. 193 194The acceptable values are defined by :c:type:`fe_code_rate`. 195 196 197.. _DTV-VOLTAGE: 198 199DTV_VOLTAGE 200=========== 201 202Used on satellite delivery systems. 203 204The voltage is usually used with non-DiSEqC capable LNBs to switch the 205polarzation (horizontal/vertical). When using DiSEqC epuipment this 206voltage has to be switched consistently to the DiSEqC commands as 207described in the DiSEqC spec. 208 209The acceptable values are defined by :c:type:`fe_sec_voltage`. 210 211 212.. _DTV-TONE: 213 214DTV_TONE 215======== 216 217Currently not used. 218 219 220.. _DTV-PILOT: 221 222DTV_PILOT 223========= 224 225Used on DVB-S2. 226 227Sets DVB-S2 pilot. 228 229The acceptable values are defined by :c:type:`fe_pilot`. 230 231 232.. _DTV-ROLLOFF: 233 234DTV_ROLLOFF 235=========== 236 237Used on DVB-S2. 238 239Sets DVB-S2 rolloff. 240 241The acceptable values are defined by :c:type:`fe_rolloff`. 242 243 244.. _DTV-DISEQC-SLAVE-REPLY: 245 246DTV_DISEQC_SLAVE_REPLY 247====================== 248 249Currently not implemented. 250 251 252.. _DTV-FE-CAPABILITY-COUNT: 253 254DTV_FE_CAPABILITY_COUNT 255======================= 256 257Currently not implemented. 258 259 260.. _DTV-FE-CAPABILITY: 261 262DTV_FE_CAPABILITY 263================= 264 265Currently not implemented. 266 267 268.. _DTV-DELIVERY-SYSTEM: 269 270DTV_DELIVERY_SYSTEM 271=================== 272 273Specifies the type of the delivery system. 274 275The acceptable values are defined by :c:type:`fe_delivery_system`. 276 277 278.. _DTV-ISDBT-PARTIAL-RECEPTION: 279 280DTV_ISDBT_PARTIAL_RECEPTION 281=========================== 282 283Used only on ISDB. 284 285If ``DTV_ISDBT_SOUND_BROADCASTING`` is '0' this bit-field represents 286whether the channel is in partial reception mode or not. 287 288If '1' ``DTV_ISDBT_LAYERA_*`` values are assigned to the center segment 289and ``DTV_ISDBT_LAYERA_SEGMENT_COUNT`` has to be '1'. 290 291If in addition ``DTV_ISDBT_SOUND_BROADCASTING`` is '1' 292``DTV_ISDBT_PARTIAL_RECEPTION`` represents whether this ISDB-Tsb channel 293is consisting of one segment and layer or three segments and two layers. 294 295Possible values: 0, 1, -1 (AUTO) 296 297 298.. _DTV-ISDBT-SOUND-BROADCASTING: 299 300DTV_ISDBT_SOUND_BROADCASTING 301============================ 302 303Used only on ISDB. 304 305This field represents whether the other DTV_ISDBT_*-parameters are 306referring to an ISDB-T and an ISDB-Tsb channel. (See also 307``DTV_ISDBT_PARTIAL_RECEPTION``). 308 309Possible values: 0, 1, -1 (AUTO) 310 311 312.. _DTV-ISDBT-SB-SUBCHANNEL-ID: 313 314DTV_ISDBT_SB_SUBCHANNEL_ID 315========================== 316 317Used only on ISDB. 318 319This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 320 321(Note of the author: This might not be the correct description of the 322``SUBCHANNEL-ID`` in all details, but it is my understanding of the 323technical background needed to program a device) 324 325An ISDB-Tsb channel (1 or 3 segments) can be broadcasted alone or in a 326set of connected ISDB-Tsb channels. In this set of channels every 327channel can be received independently. The number of connected ISDB-Tsb 328segment can vary, e.g. depending on the frequency spectrum bandwidth 329available. 330 331Example: Assume 8 ISDB-Tsb connected segments are broadcasted. The 332broadcaster has several possibilities to put those channels in the air: 333Assuming a normal 13-segment ISDB-T spectrum he can align the 8 segments 334from position 1-8 to 5-13 or anything in between. 335 336The underlying layer of segments are subchannels: each segment is 337consisting of several subchannels with a predefined IDs. A sub-channel 338is used to help the demodulator to synchronize on the channel. 339 340An ISDB-T channel is always centered over all sub-channels. As for the 341example above, in ISDB-Tsb it is no longer as simple as that. 342 343``The DTV_ISDBT_SB_SUBCHANNEL_ID`` parameter is used to give the 344sub-channel ID of the segment to be demodulated. 345 346Possible values: 0 .. 41, -1 (AUTO) 347 348 349.. _DTV-ISDBT-SB-SEGMENT-IDX: 350 351DTV_ISDBT_SB_SEGMENT_IDX 352======================== 353 354Used only on ISDB. 355 356This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 357 358``DTV_ISDBT_SB_SEGMENT_IDX`` gives the index of the segment to be 359demodulated for an ISDB-Tsb channel where several of them are 360transmitted in the connected manner. 361 362Possible values: 0 .. ``DTV_ISDBT_SB_SEGMENT_COUNT`` - 1 363 364Note: This value cannot be determined by an automatic channel search. 365 366 367.. _DTV-ISDBT-SB-SEGMENT-COUNT: 368 369DTV_ISDBT_SB_SEGMENT_COUNT 370========================== 371 372Used only on ISDB. 373 374This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 375 376``DTV_ISDBT_SB_SEGMENT_COUNT`` gives the total count of connected 377ISDB-Tsb channels. 378 379Possible values: 1 .. 13 380 381Note: This value cannot be determined by an automatic channel search. 382 383 384.. _isdb-hierq-layers: 385 386DTV-ISDBT-LAYER[A-C] parameters 387=============================== 388 389Used only on ISDB. 390 391ISDB-T channels can be coded hierarchically. As opposed to DVB-T in 392ISDB-T hierarchical layers can be decoded simultaneously. For that 393reason a ISDB-T demodulator has 3 Viterbi and 3 Reed-Solomon decoders. 394 395ISDB-T has 3 hierarchical layers which each can use a part of the 396available segments. The total number of segments over all layers has to 39713 in ISDB-T. 398 399There are 3 parameter sets, for Layers A, B and C. 400 401 402.. _DTV-ISDBT-LAYER-ENABLED: 403 404DTV_ISDBT_LAYER_ENABLED 405----------------------- 406 407Used only on ISDB. 408 409Hierarchical reception in ISDB-T is achieved by enabling or disabling 410layers in the decoding process. Setting all bits of 411``DTV_ISDBT_LAYER_ENABLED`` to '1' forces all layers (if applicable) to 412be demodulated. This is the default. 413 414If the channel is in the partial reception mode 415(``DTV_ISDBT_PARTIAL_RECEPTION`` = 1) the central segment can be decoded 416independently of the other 12 segments. In that mode layer A has to have 417a ``SEGMENT_COUNT`` of 1. 418 419In ISDB-Tsb only layer A is used, it can be 1 or 3 in ISDB-Tsb according 420to ``DTV_ISDBT_PARTIAL_RECEPTION``. ``SEGMENT_COUNT`` must be filled 421accordingly. 422 423Only the values of the first 3 bits are used. Other bits will be silently ignored: 424 425``DTV_ISDBT_LAYER_ENABLED`` bit 0: layer A enabled 426 427``DTV_ISDBT_LAYER_ENABLED`` bit 1: layer B enabled 428 429``DTV_ISDBT_LAYER_ENABLED`` bit 2: layer C enabled 430 431``DTV_ISDBT_LAYER_ENABLED`` bits 3-31: unused 432 433 434.. _DTV-ISDBT-LAYER-FEC: 435 436DTV_ISDBT_LAYER[A-C]_FEC 437------------------------ 438 439Used only on ISDB. 440 441The Forward Error Correction mechanism used by a given ISDB Layer, as 442defined by :c:type:`fe_code_rate`. 443 444 445Possible values are: ``FEC_AUTO``, ``FEC_1_2``, ``FEC_2_3``, ``FEC_3_4``, 446``FEC_5_6``, ``FEC_7_8`` 447 448 449.. _DTV-ISDBT-LAYER-MODULATION: 450 451DTV_ISDBT_LAYER[A-C]_MODULATION 452------------------------------- 453 454Used only on ISDB. 455 456The modulation used by a given ISDB Layer, as defined by 457:c:type:`fe_modulation`. 458 459Possible values are: ``QAM_AUTO``, ``QPSK``, ``QAM_16``, ``QAM_64``, ``DQPSK`` 460 461.. note:: 462 463 #. If layer C is ``DQPSK``, then layer B has to be ``DQPSK``. 464 465 #. If layer B is ``DQPSK`` and ``DTV_ISDBT_PARTIAL_RECEPTION``\ = 0, 466 then layer has to be ``DQPSK``. 467 468 469.. _DTV-ISDBT-LAYER-SEGMENT-COUNT: 470 471DTV_ISDBT_LAYER[A-C]_SEGMENT_COUNT 472---------------------------------- 473 474Used only on ISDB. 475 476Possible values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1 (AUTO) 477 478Note: Truth table for ``DTV_ISDBT_SOUND_BROADCASTING`` and 479``DTV_ISDBT_PARTIAL_RECEPTION`` and ``LAYER[A-C]_SEGMENT_COUNT`` 480 481.. _isdbt-layer_seg-cnt-table: 482 483.. flat-table:: Truth table for ISDB-T Sound Broadcasting 484 :header-rows: 1 485 :stub-columns: 0 486 487 488 - .. row 1 489 490 - Partial Reception 491 492 - Sound Broadcasting 493 494 - Layer A width 495 496 - Layer B width 497 498 - Layer C width 499 500 - total width 501 502 - .. row 2 503 504 - 0 505 506 - 0 507 508 - 1 .. 13 509 510 - 1 .. 13 511 512 - 1 .. 13 513 514 - 13 515 516 - .. row 3 517 518 - 1 519 520 - 0 521 522 - 1 523 524 - 1 .. 13 525 526 - 1 .. 13 527 528 - 13 529 530 - .. row 4 531 532 - 0 533 534 - 1 535 536 - 1 537 538 - 0 539 540 - 0 541 542 - 1 543 544 - .. row 5 545 546 - 1 547 548 - 1 549 550 - 1 551 552 - 2 553 554 - 0 555 556 - 13 557 558 559 560.. _DTV-ISDBT-LAYER-TIME-INTERLEAVING: 561 562DTV_ISDBT_LAYER[A-C]_TIME_INTERLEAVING 563-------------------------------------- 564 565Used only on ISDB. 566 567Valid values: 0, 1, 2, 4, -1 (AUTO) 568 569when DTV_ISDBT_SOUND_BROADCASTING is active, value 8 is also valid. 570 571Note: The real time interleaving length depends on the mode (fft-size). 572The values here are referring to what can be found in the 573TMCC-structure, as shown in the table below. 574 575 576.. c:type:: isdbt_layer_interleaving_table 577 578.. flat-table:: ISDB-T time interleaving modes 579 :header-rows: 1 580 :stub-columns: 0 581 582 583 - .. row 1 584 585 - ``DTV_ISDBT_LAYER[A-C]_TIME_INTERLEAVING`` 586 587 - Mode 1 (2K FFT) 588 589 - Mode 2 (4K FFT) 590 591 - Mode 3 (8K FFT) 592 593 - .. row 2 594 595 - 0 596 597 - 0 598 599 - 0 600 601 - 0 602 603 - .. row 3 604 605 - 1 606 607 - 4 608 609 - 2 610 611 - 1 612 613 - .. row 4 614 615 - 2 616 617 - 8 618 619 - 4 620 621 - 2 622 623 - .. row 5 624 625 - 4 626 627 - 16 628 629 - 8 630 631 - 4 632 633 634 635.. _DTV-ATSCMH-FIC-VER: 636 637DTV_ATSCMH_FIC_VER 638------------------ 639 640Used only on ATSC-MH. 641 642Version number of the FIC (Fast Information Channel) signaling data. 643 644FIC is used for relaying information to allow rapid service acquisition 645by the receiver. 646 647Possible values: 0, 1, 2, 3, ..., 30, 31 648 649 650.. _DTV-ATSCMH-PARADE-ID: 651 652DTV_ATSCMH_PARADE_ID 653-------------------- 654 655Used only on ATSC-MH. 656 657Parade identification number 658 659A parade is a collection of up to eight MH groups, conveying one or two 660ensembles. 661 662Possible values: 0, 1, 2, 3, ..., 126, 127 663 664 665.. _DTV-ATSCMH-NOG: 666 667DTV_ATSCMH_NOG 668-------------- 669 670Used only on ATSC-MH. 671 672Number of MH groups per MH subframe for a designated parade. 673 674Possible values: 1, 2, 3, 4, 5, 6, 7, 8 675 676 677.. _DTV-ATSCMH-TNOG: 678 679DTV_ATSCMH_TNOG 680--------------- 681 682Used only on ATSC-MH. 683 684Total number of MH groups including all MH groups belonging to all MH 685parades in one MH subframe. 686 687Possible values: 0, 1, 2, 3, ..., 30, 31 688 689 690.. _DTV-ATSCMH-SGN: 691 692DTV_ATSCMH_SGN 693-------------- 694 695Used only on ATSC-MH. 696 697Start group number. 698 699Possible values: 0, 1, 2, 3, ..., 14, 15 700 701 702.. _DTV-ATSCMH-PRC: 703 704DTV_ATSCMH_PRC 705-------------- 706 707Used only on ATSC-MH. 708 709Parade repetition cycle. 710 711Possible values: 1, 2, 3, 4, 5, 6, 7, 8 712 713 714.. _DTV-ATSCMH-RS-FRAME-MODE: 715 716DTV_ATSCMH_RS_FRAME_MODE 717------------------------ 718 719Used only on ATSC-MH. 720 721Reed Solomon (RS) frame mode. 722 723The acceptable values are defined by :c:type:`atscmh_rs_frame_mode`. 724 725 726.. _DTV-ATSCMH-RS-FRAME-ENSEMBLE: 727 728DTV_ATSCMH_RS_FRAME_ENSEMBLE 729---------------------------- 730 731Used only on ATSC-MH. 732 733Reed Solomon(RS) frame ensemble. 734 735The acceptable values are defined by :c:type:`atscmh_rs_frame_ensemble`. 736 737 738.. _DTV-ATSCMH-RS-CODE-MODE-PRI: 739 740DTV_ATSCMH_RS_CODE_MODE_PRI 741--------------------------- 742 743Used only on ATSC-MH. 744 745Reed Solomon (RS) code mode (primary). 746 747The acceptable values are defined by :c:type:`atscmh_rs_code_mode`. 748 749 750.. _DTV-ATSCMH-RS-CODE-MODE-SEC: 751 752DTV_ATSCMH_RS_CODE_MODE_SEC 753--------------------------- 754 755Used only on ATSC-MH. 756 757Reed Solomon (RS) code mode (secondary). 758 759The acceptable values are defined by :c:type:`atscmh_rs_code_mode`. 760 761 762.. _DTV-ATSCMH-SCCC-BLOCK-MODE: 763 764DTV_ATSCMH_SCCC_BLOCK_MODE 765-------------------------- 766 767Used only on ATSC-MH. 768 769Series Concatenated Convolutional Code Block Mode. 770 771The acceptable values are defined by :c:type:`atscmh_sccc_block_mode`. 772 773 774.. _DTV-ATSCMH-SCCC-CODE-MODE-A: 775 776DTV_ATSCMH_SCCC_CODE_MODE_A 777--------------------------- 778 779Used only on ATSC-MH. 780 781Series Concatenated Convolutional Code Rate. 782 783The acceptable values are defined by :c:type:`atscmh_sccc_code_mode`. 784 785.. _DTV-ATSCMH-SCCC-CODE-MODE-B: 786 787DTV_ATSCMH_SCCC_CODE_MODE_B 788--------------------------- 789 790Used only on ATSC-MH. 791 792Series Concatenated Convolutional Code Rate. 793 794Possible values are the same as documented on enum 795:c:type:`atscmh_sccc_code_mode`. 796 797 798.. _DTV-ATSCMH-SCCC-CODE-MODE-C: 799 800DTV_ATSCMH_SCCC_CODE_MODE_C 801--------------------------- 802 803Used only on ATSC-MH. 804 805Series Concatenated Convolutional Code Rate. 806 807Possible values are the same as documented on enum 808:c:type:`atscmh_sccc_code_mode`. 809 810 811.. _DTV-ATSCMH-SCCC-CODE-MODE-D: 812 813DTV_ATSCMH_SCCC_CODE_MODE_D 814--------------------------- 815 816Used only on ATSC-MH. 817 818Series Concatenated Convolutional Code Rate. 819 820Possible values are the same as documented on enum 821:c:type:`atscmh_sccc_code_mode`. 822 823 824.. _DTV-API-VERSION: 825 826DTV_API_VERSION 827=============== 828 829Returns the major/minor version of the Digital TV API 830 831 832.. _DTV-CODE-RATE-HP: 833 834DTV_CODE_RATE_HP 835================ 836 837Used on terrestrial transmissions. 838 839The acceptable values are defined by :c:type:`fe_transmit_mode`. 840 841 842.. _DTV-CODE-RATE-LP: 843 844DTV_CODE_RATE_LP 845================ 846 847Used on terrestrial transmissions. 848 849The acceptable values are defined by :c:type:`fe_transmit_mode`. 850 851 852.. _DTV-GUARD-INTERVAL: 853 854DTV_GUARD_INTERVAL 855================== 856 857The acceptable values are defined by :c:type:`fe_guard_interval`. 858 859.. note:: 860 861 #. If ``DTV_GUARD_INTERVAL`` is set the ``GUARD_INTERVAL_AUTO`` the 862 hardware will try to find the correct guard interval (if capable) and 863 will use TMCC to fill in the missing parameters. 864 #. Intervals ``GUARD_INTERVAL_1_128``, ``GUARD_INTERVAL_19_128`` 865 and ``GUARD_INTERVAL_19_256`` are used only for DVB-T2 at 866 present. 867 #. Intervals ``GUARD_INTERVAL_PN420``, ``GUARD_INTERVAL_PN595`` and 868 ``GUARD_INTERVAL_PN945`` are used only for DMTB at the present. 869 On such standard, only those intervals and ``GUARD_INTERVAL_AUTO`` 870 are valid. 871 872.. _DTV-TRANSMISSION-MODE: 873 874DTV_TRANSMISSION_MODE 875===================== 876 877 878Used only on OFTM-based standards, e. g. DVB-T/T2, ISDB-T, DTMB. 879 880Specifies the FFT size (with corresponds to the approximate number of 881carriers) used by the standard. 882 883The acceptable values are defined by :c:type:`fe_transmit_mode`. 884 885.. note:: 886 887 #. ISDB-T supports three carrier/symbol-size: 8K, 4K, 2K. It is called 888 **mode** on such standard, and are numbered from 1 to 3: 889 890 ==== ======== ======================== 891 Mode FFT size Transmission mode 892 ==== ======== ======================== 893 1 2K ``TRANSMISSION_MODE_2K`` 894 2 4K ``TRANSMISSION_MODE_4K`` 895 3 8K ``TRANSMISSION_MODE_8K`` 896 ==== ======== ======================== 897 898 #. If ``DTV_TRANSMISSION_MODE`` is set the ``TRANSMISSION_MODE_AUTO`` 899 the hardware will try to find the correct FFT-size (if capable) and 900 will use TMCC to fill in the missing parameters. 901 902 #. DVB-T specifies 2K and 8K as valid sizes. 903 904 #. DVB-T2 specifies 1K, 2K, 4K, 8K, 16K and 32K. 905 906 #. DTMB specifies C1 and C3780. 907 908 909.. _DTV-HIERARCHY: 910 911DTV_HIERARCHY 912============= 913 914Used only on DVB-T and DVB-T2. 915 916Frontend hierarchy. 917 918The acceptable values are defined by :c:type:`fe_hierarchy`. 919 920 921.. _DTV-STREAM-ID: 922 923DTV_STREAM_ID 924============= 925 926Used on DVB-S2, DVB-T2 and ISDB-S. 927 928DVB-S2, DVB-T2 and ISDB-S support the transmission of several streams on 929a single transport stream. This property enables the digital TV driver to 930handle substream filtering, when supported by the hardware. By default, 931substream filtering is disabled. 932 933For DVB-S2 and DVB-T2, the valid substream id range is from 0 to 255. 934 935For ISDB, the valid substream id range is from 1 to 65535. 936 937To disable it, you should use the special macro NO_STREAM_ID_FILTER. 938 939Note: any value outside the id range also disables filtering. 940 941 942.. _DTV-DVBT2-PLP-ID-LEGACY: 943 944DTV_DVBT2_PLP_ID_LEGACY 945======================= 946 947Obsolete, replaced with DTV_STREAM_ID. 948 949 950.. _DTV-ENUM-DELSYS: 951 952DTV_ENUM_DELSYS 953=============== 954 955A Multi standard frontend needs to advertise the delivery systems 956provided. Applications need to enumerate the provided delivery systems, 957before using any other operation with the frontend. Prior to it's 958introduction, FE_GET_INFO was used to determine a frontend type. A 959frontend which provides more than a single delivery system, 960FE_GET_INFO doesn't help much. Applications which intends to use a 961multistandard frontend must enumerate the delivery systems associated 962with it, rather than trying to use FE_GET_INFO. In the case of a 963legacy frontend, the result is just the same as with FE_GET_INFO, but 964in a more structured format 965 966The acceptable values are defined by :c:type:`fe_delivery_system`. 967 968 969.. _DTV-INTERLEAVING: 970 971DTV_INTERLEAVING 972================ 973 974Time interleaving to be used. 975 976The acceptable values are defined by :c:type:`fe_interleaving`. 977 978 979.. _DTV-LNA: 980 981DTV_LNA 982======= 983 984Low-noise amplifier. 985 986Hardware might offer controllable LNA which can be set manually using 987that parameter. Usually LNA could be found only from terrestrial devices 988if at all. 989 990Possible values: 0, 1, LNA_AUTO 991 9920, LNA off 993 9941, LNA on 995 996use the special macro LNA_AUTO to set LNA auto 997 998 999.. _DTV-SCRAMBLING-SEQUENCE-INDEX: 1000 1001DTV_SCRAMBLING_SEQUENCE_INDEX 1002============================= 1003 1004Used on DVB-S2. 1005 1006This 18 bit field, when present, carries the index of the DVB-S2 physical 1007layer scrambling sequence as defined in clause 5.5.4 of EN 302 307. 1008There is no explicit signalling method to convey scrambling sequence index 1009to the receiver. If S2 satellite delivery system descriptor is available 1010it can be used to read the scrambling sequence index (EN 300 468 table 41). 1011 1012By default, gold scrambling sequence index 0 is used. 1013 1014The valid scrambling sequence index range is from 0 to 262142. 1015