1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2 3.. _fe_property_parameters: 4 5****************************** 6Digital TV property parameters 7****************************** 8 9There are several different Digital TV parameters that can be used by 10:ref:`FE_SET_PROPERTY and FE_GET_PROPERTY ioctls<FE_GET_PROPERTY>`. 11This section describes each of them. Please notice, however, that only 12a subset of them are needed to setup a frontend. 13 14 15.. _DTV-UNDEFINED: 16 17DTV_UNDEFINED 18============= 19 20Used internally. A GET/SET operation for it won't change or return 21anything. 22 23 24.. _DTV-TUNE: 25 26DTV_TUNE 27======== 28 29Interpret the cache of data, build either a traditional frontend 30tunerequest so we can pass validation in the ``FE_SET_FRONTEND`` ioctl. 31 32 33.. _DTV-CLEAR: 34 35DTV_CLEAR 36========= 37 38Reset a cache of data specific to the frontend here. This does not 39effect hardware. 40 41 42.. _DTV-FREQUENCY: 43 44DTV_FREQUENCY 45============= 46 47Frequency of the digital TV transponder/channel. 48 49.. note:: 50 51 #. For satellite delivery systems, the frequency is in kHz. 52 53 #. For cable and terrestrial delivery systems, the frequency is in 54 Hz. 55 56 #. On most delivery systems, the frequency is the center frequency 57 of the transponder/channel. The exception is for ISDB-T, where 58 the main carrier has a 1/7 offset from the center. 59 60 #. For ISDB-T, the channels are usually transmitted with an offset of 61 about 143kHz. E.g. a valid frequency could be 474,143 kHz. The 62 stepping is bound to the bandwidth of the channel which is 63 typically 6MHz. 64 65 #. In ISDB-Tsb, the channel consists of only one or three segments the 66 frequency step is 429kHz, 3*429 respectively. 67 68 69.. _DTV-MODULATION: 70 71DTV_MODULATION 72============== 73 74Specifies the frontend modulation type for delivery systems that 75supports more multiple modulations. 76 77The modulation can be one of the types defined by enum :c:type:`fe_modulation`. 78 79Most of the digital TV standards offers more than one possible 80modulation type. 81 82The table below presents a summary of the types of modulation types 83supported by each delivery system, as currently defined by specs. 84 85======================= ======================================================= 86Standard Modulation types 87======================= ======================================================= 88ATSC (version 1) 8-VSB and 16-VSB. 89DMTB 4-QAM, 16-QAM, 32-QAM, 64-QAM and 4-QAM-NR. 90DVB-C Annex A/C 16-QAM, 32-QAM, 64-QAM and 256-QAM. 91DVB-C Annex B 64-QAM. 92DVB-C2 QPSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM and 4096-QAM. 93DVB-T QPSK, 16-QAM and 64-QAM. 94DVB-T2 QPSK, 16-QAM, 64-QAM and 256-QAM. 95DVB-S No need to set. It supports only QPSK. 96DVB-S2 QPSK, 8-PSK, 16-APSK and 32-APSK. 97DVB-S2X 8-APSK-L, 16-APSK-L, 32-APSK-L, 64-APSK and 64-APSK-L. 98ISDB-T QPSK, DQPSK, 16-QAM and 64-QAM. 99ISDB-S 8-PSK, QPSK and BPSK. 100======================= ======================================================= 101 102.. note:: 103 104 As DVB-S2X specifies extensions to the DVB-S2 standard, the same 105 delivery system enum value is used (SYS_DVBS2). 106 107 Please notice that some of the above modulation types may not be 108 defined currently at the Kernel. The reason is simple: no driver 109 needed such definition yet. 110 111 112.. _DTV-BANDWIDTH-HZ: 113 114DTV_BANDWIDTH_HZ 115================ 116 117Bandwidth for the channel, in HZ. 118 119Should be set only for terrestrial delivery systems. 120 121Possible values: ``1712000``, ``5000000``, ``6000000``, ``7000000``, 122``8000000``, ``10000000``. 123 124======================= ======================================================= 125Terrestrial Standard Possible values for bandwidth 126======================= ======================================================= 127ATSC (version 1) No need to set. It is always 6MHz. 128DMTB No need to set. It is always 8MHz. 129DVB-T 6MHz, 7MHz and 8MHz. 130DVB-T2 1.172 MHz, 5MHz, 6MHz, 7MHz, 8MHz and 10MHz 131ISDB-T 5MHz, 6MHz, 7MHz and 8MHz, although most places 132 use 6MHz. 133======================= ======================================================= 134 135 136.. note:: 137 138 139 #. For ISDB-Tsb, the bandwidth can vary depending on the number of 140 connected segments. 141 142 It can be easily derived from other parameters 143 (DTV_ISDBT_SB_SEGMENT_IDX, DTV_ISDBT_SB_SEGMENT_COUNT). 144 145 #. On Satellite and Cable delivery systems, the bandwidth depends on 146 the symbol rate. So, the Kernel will silently ignore any setting 147 :ref:`DTV-BANDWIDTH-HZ`. I will however fill it back with a 148 bandwidth estimation. 149 150 Such bandwidth estimation takes into account the symbol rate set with 151 :ref:`DTV-SYMBOL-RATE`, and the rolloff factor, with is fixed for 152 DVB-C and DVB-S. 153 154 For DVB-S2, the rolloff should also be set via :ref:`DTV-ROLLOFF`. 155 156 157.. _DTV-INVERSION: 158 159DTV_INVERSION 160============= 161 162Specifies if the frontend should do spectral inversion or not. 163 164The acceptable values are defined by :c:type:`fe_spectral_inversion`. 165 166 167.. _DTV-DISEQC-MASTER: 168 169DTV_DISEQC_MASTER 170================= 171 172Currently not implemented. 173 174 175.. _DTV-SYMBOL-RATE: 176 177DTV_SYMBOL_RATE 178=============== 179 180Used on cable and satellite delivery systems. 181 182Digital TV symbol rate, in bauds (symbols/second). 183 184 185.. _DTV-INNER-FEC: 186 187DTV_INNER_FEC 188============= 189 190Used on cable and satellite delivery systems. 191 192The acceptable values are defined by :c:type:`fe_code_rate`. 193 194 195.. _DTV-VOLTAGE: 196 197DTV_VOLTAGE 198=========== 199 200Used on satellite delivery systems. 201 202The voltage is usually used with non-DiSEqC capable LNBs to switch the 203polarzation (horizontal/vertical). When using DiSEqC epuipment this 204voltage has to be switched consistently to the DiSEqC commands as 205described in the DiSEqC spec. 206 207The acceptable values are defined by :c:type:`fe_sec_voltage`. 208 209 210.. _DTV-TONE: 211 212DTV_TONE 213======== 214 215Currently not used. 216 217 218.. _DTV-PILOT: 219 220DTV_PILOT 221========= 222 223Used on DVB-S2. 224 225Sets DVB-S2 pilot. 226 227The acceptable values are defined by :c:type:`fe_pilot`. 228 229 230.. _DTV-ROLLOFF: 231 232DTV_ROLLOFF 233=========== 234 235Used on DVB-S2. 236 237Sets DVB-S2 rolloff. 238 239The acceptable values are defined by :c:type:`fe_rolloff`. 240 241 242.. _DTV-DISEQC-SLAVE-REPLY: 243 244DTV_DISEQC_SLAVE_REPLY 245====================== 246 247Currently not implemented. 248 249 250.. _DTV-FE-CAPABILITY-COUNT: 251 252DTV_FE_CAPABILITY_COUNT 253======================= 254 255Currently not implemented. 256 257 258.. _DTV-FE-CAPABILITY: 259 260DTV_FE_CAPABILITY 261================= 262 263Currently not implemented. 264 265 266.. _DTV-DELIVERY-SYSTEM: 267 268DTV_DELIVERY_SYSTEM 269=================== 270 271Specifies the type of the delivery system. 272 273The acceptable values are defined by :c:type:`fe_delivery_system`. 274 275 276.. _DTV-ISDBT-PARTIAL-RECEPTION: 277 278DTV_ISDBT_PARTIAL_RECEPTION 279=========================== 280 281Used only on ISDB. 282 283If ``DTV_ISDBT_SOUND_BROADCASTING`` is '0' this bit-field represents 284whether the channel is in partial reception mode or not. 285 286If '1' ``DTV_ISDBT_LAYERA_*`` values are assigned to the center segment 287and ``DTV_ISDBT_LAYERA_SEGMENT_COUNT`` has to be '1'. 288 289If in addition ``DTV_ISDBT_SOUND_BROADCASTING`` is '1' 290``DTV_ISDBT_PARTIAL_RECEPTION`` represents whether this ISDB-Tsb channel 291is consisting of one segment and layer or three segments and two layers. 292 293Possible values: 0, 1, -1 (AUTO) 294 295 296.. _DTV-ISDBT-SOUND-BROADCASTING: 297 298DTV_ISDBT_SOUND_BROADCASTING 299============================ 300 301Used only on ISDB. 302 303This field represents whether the other DTV_ISDBT_*-parameters are 304referring to an ISDB-T and an ISDB-Tsb channel. (See also 305``DTV_ISDBT_PARTIAL_RECEPTION``). 306 307Possible values: 0, 1, -1 (AUTO) 308 309 310.. _DTV-ISDBT-SB-SUBCHANNEL-ID: 311 312DTV_ISDBT_SB_SUBCHANNEL_ID 313========================== 314 315Used only on ISDB. 316 317This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 318 319(Note of the author: This might not be the correct description of the 320``SUBCHANNEL-ID`` in all details, but it is my understanding of the 321technical background needed to program a device) 322 323An ISDB-Tsb channel (1 or 3 segments) can be broadcasted alone or in a 324set of connected ISDB-Tsb channels. In this set of channels every 325channel can be received independently. The number of connected ISDB-Tsb 326segment can vary, e.g. depending on the frequency spectrum bandwidth 327available. 328 329Example: Assume 8 ISDB-Tsb connected segments are broadcasted. The 330broadcaster has several possibilities to put those channels in the air: 331Assuming a normal 13-segment ISDB-T spectrum he can align the 8 segments 332from position 1-8 to 5-13 or anything in between. 333 334The underlying layer of segments are subchannels: each segment is 335consisting of several subchannels with a predefined IDs. A sub-channel 336is used to help the demodulator to synchronize on the channel. 337 338An ISDB-T channel is always centered over all sub-channels. As for the 339example above, in ISDB-Tsb it is no longer as simple as that. 340 341``The DTV_ISDBT_SB_SUBCHANNEL_ID`` parameter is used to give the 342sub-channel ID of the segment to be demodulated. 343 344Possible values: 0 .. 41, -1 (AUTO) 345 346 347.. _DTV-ISDBT-SB-SEGMENT-IDX: 348 349DTV_ISDBT_SB_SEGMENT_IDX 350======================== 351 352Used only on ISDB. 353 354This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 355 356``DTV_ISDBT_SB_SEGMENT_IDX`` gives the index of the segment to be 357demodulated for an ISDB-Tsb channel where several of them are 358transmitted in the connected manner. 359 360Possible values: 0 .. ``DTV_ISDBT_SB_SEGMENT_COUNT`` - 1 361 362Note: This value cannot be determined by an automatic channel search. 363 364 365.. _DTV-ISDBT-SB-SEGMENT-COUNT: 366 367DTV_ISDBT_SB_SEGMENT_COUNT 368========================== 369 370Used only on ISDB. 371 372This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 373 374``DTV_ISDBT_SB_SEGMENT_COUNT`` gives the total count of connected 375ISDB-Tsb channels. 376 377Possible values: 1 .. 13 378 379Note: This value cannot be determined by an automatic channel search. 380 381 382.. _isdb-hierq-layers: 383 384DTV-ISDBT-LAYER[A-C] parameters 385=============================== 386 387Used only on ISDB. 388 389ISDB-T channels can be coded hierarchically. As opposed to DVB-T in 390ISDB-T hierarchical layers can be decoded simultaneously. For that 391reason a ISDB-T demodulator has 3 Viterbi and 3 Reed-Solomon decoders. 392 393ISDB-T has 3 hierarchical layers which each can use a part of the 394available segments. The total number of segments over all layers has to 39513 in ISDB-T. 396 397There are 3 parameter sets, for Layers A, B and C. 398 399 400.. _DTV-ISDBT-LAYER-ENABLED: 401 402DTV_ISDBT_LAYER_ENABLED 403----------------------- 404 405Used only on ISDB. 406 407Hierarchical reception in ISDB-T is achieved by enabling or disabling 408layers in the decoding process. Setting all bits of 409``DTV_ISDBT_LAYER_ENABLED`` to '1' forces all layers (if applicable) to 410be demodulated. This is the default. 411 412If the channel is in the partial reception mode 413(``DTV_ISDBT_PARTIAL_RECEPTION`` = 1) the central segment can be decoded 414independently of the other 12 segments. In that mode layer A has to have 415a ``SEGMENT_COUNT`` of 1. 416 417In ISDB-Tsb only layer A is used, it can be 1 or 3 in ISDB-Tsb according 418to ``DTV_ISDBT_PARTIAL_RECEPTION``. ``SEGMENT_COUNT`` must be filled 419accordingly. 420 421Only the values of the first 3 bits are used. Other bits will be silently ignored: 422 423``DTV_ISDBT_LAYER_ENABLED`` bit 0: layer A enabled 424 425``DTV_ISDBT_LAYER_ENABLED`` bit 1: layer B enabled 426 427``DTV_ISDBT_LAYER_ENABLED`` bit 2: layer C enabled 428 429``DTV_ISDBT_LAYER_ENABLED`` bits 3-31: unused 430 431 432.. _DTV-ISDBT-LAYER-FEC: 433 434DTV_ISDBT_LAYER[A-C]_FEC 435------------------------ 436 437Used only on ISDB. 438 439The Forward Error Correction mechanism used by a given ISDB Layer, as 440defined by :c:type:`fe_code_rate`. 441 442 443Possible values are: ``FEC_AUTO``, ``FEC_1_2``, ``FEC_2_3``, ``FEC_3_4``, 444``FEC_5_6``, ``FEC_7_8`` 445 446 447.. _DTV-ISDBT-LAYER-MODULATION: 448 449DTV_ISDBT_LAYER[A-C]_MODULATION 450------------------------------- 451 452Used only on ISDB. 453 454The modulation used by a given ISDB Layer, as defined by 455:c:type:`fe_modulation`. 456 457Possible values are: ``QAM_AUTO``, ``QPSK``, ``QAM_16``, ``QAM_64``, ``DQPSK`` 458 459.. note:: 460 461 #. If layer C is ``DQPSK``, then layer B has to be ``DQPSK``. 462 463 #. If layer B is ``DQPSK`` and ``DTV_ISDBT_PARTIAL_RECEPTION``\ = 0, 464 then layer has to be ``DQPSK``. 465 466 467.. _DTV-ISDBT-LAYER-SEGMENT-COUNT: 468 469DTV_ISDBT_LAYER[A-C]_SEGMENT_COUNT 470---------------------------------- 471 472Used only on ISDB. 473 474Possible values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1 (AUTO) 475 476Note: Truth table for ``DTV_ISDBT_SOUND_BROADCASTING`` and 477``DTV_ISDBT_PARTIAL_RECEPTION`` and ``LAYER[A-C]_SEGMENT_COUNT`` 478 479.. _isdbt-layer_seg-cnt-table: 480 481.. flat-table:: Truth table for ISDB-T Sound Broadcasting 482 :header-rows: 1 483 :stub-columns: 0 484 485 486 - .. row 1 487 488 - Partial Reception 489 490 - Sound Broadcasting 491 492 - Layer A width 493 494 - Layer B width 495 496 - Layer C width 497 498 - total width 499 500 - .. row 2 501 502 - 0 503 504 - 0 505 506 - 1 .. 13 507 508 - 1 .. 13 509 510 - 1 .. 13 511 512 - 13 513 514 - .. row 3 515 516 - 1 517 518 - 0 519 520 - 1 521 522 - 1 .. 13 523 524 - 1 .. 13 525 526 - 13 527 528 - .. row 4 529 530 - 0 531 532 - 1 533 534 - 1 535 536 - 0 537 538 - 0 539 540 - 1 541 542 - .. row 5 543 544 - 1 545 546 - 1 547 548 - 1 549 550 - 2 551 552 - 0 553 554 - 13 555 556 557 558.. _DTV-ISDBT-LAYER-TIME-INTERLEAVING: 559 560DTV_ISDBT_LAYER[A-C]_TIME_INTERLEAVING 561-------------------------------------- 562 563Used only on ISDB. 564 565Valid values: 0, 1, 2, 4, -1 (AUTO) 566 567when DTV_ISDBT_SOUND_BROADCASTING is active, value 8 is also valid. 568 569Note: The real time interleaving length depends on the mode (fft-size). 570The values here are referring to what can be found in the 571TMCC-structure, as shown in the table below. 572 573 574.. c:type:: isdbt_layer_interleaving_table 575 576.. flat-table:: ISDB-T time interleaving modes 577 :header-rows: 1 578 :stub-columns: 0 579 580 581 - .. row 1 582 583 - ``DTV_ISDBT_LAYER[A-C]_TIME_INTERLEAVING`` 584 585 - Mode 1 (2K FFT) 586 587 - Mode 2 (4K FFT) 588 589 - Mode 3 (8K FFT) 590 591 - .. row 2 592 593 - 0 594 595 - 0 596 597 - 0 598 599 - 0 600 601 - .. row 3 602 603 - 1 604 605 - 4 606 607 - 2 608 609 - 1 610 611 - .. row 4 612 613 - 2 614 615 - 8 616 617 - 4 618 619 - 2 620 621 - .. row 5 622 623 - 4 624 625 - 16 626 627 - 8 628 629 - 4 630 631 632 633.. _DTV-ATSCMH-FIC-VER: 634 635DTV_ATSCMH_FIC_VER 636------------------ 637 638Used only on ATSC-MH. 639 640Version number of the FIC (Fast Information Channel) signaling data. 641 642FIC is used for relaying information to allow rapid service acquisition 643by the receiver. 644 645Possible values: 0, 1, 2, 3, ..., 30, 31 646 647 648.. _DTV-ATSCMH-PARADE-ID: 649 650DTV_ATSCMH_PARADE_ID 651-------------------- 652 653Used only on ATSC-MH. 654 655Parade identification number 656 657A parade is a collection of up to eight MH groups, conveying one or two 658ensembles. 659 660Possible values: 0, 1, 2, 3, ..., 126, 127 661 662 663.. _DTV-ATSCMH-NOG: 664 665DTV_ATSCMH_NOG 666-------------- 667 668Used only on ATSC-MH. 669 670Number of MH groups per MH subframe for a designated parade. 671 672Possible values: 1, 2, 3, 4, 5, 6, 7, 8 673 674 675.. _DTV-ATSCMH-TNOG: 676 677DTV_ATSCMH_TNOG 678--------------- 679 680Used only on ATSC-MH. 681 682Total number of MH groups including all MH groups belonging to all MH 683parades in one MH subframe. 684 685Possible values: 0, 1, 2, 3, ..., 30, 31 686 687 688.. _DTV-ATSCMH-SGN: 689 690DTV_ATSCMH_SGN 691-------------- 692 693Used only on ATSC-MH. 694 695Start group number. 696 697Possible values: 0, 1, 2, 3, ..., 14, 15 698 699 700.. _DTV-ATSCMH-PRC: 701 702DTV_ATSCMH_PRC 703-------------- 704 705Used only on ATSC-MH. 706 707Parade repetition cycle. 708 709Possible values: 1, 2, 3, 4, 5, 6, 7, 8 710 711 712.. _DTV-ATSCMH-RS-FRAME-MODE: 713 714DTV_ATSCMH_RS_FRAME_MODE 715------------------------ 716 717Used only on ATSC-MH. 718 719Reed Solomon (RS) frame mode. 720 721The acceptable values are defined by :c:type:`atscmh_rs_frame_mode`. 722 723 724.. _DTV-ATSCMH-RS-FRAME-ENSEMBLE: 725 726DTV_ATSCMH_RS_FRAME_ENSEMBLE 727---------------------------- 728 729Used only on ATSC-MH. 730 731Reed Solomon(RS) frame ensemble. 732 733The acceptable values are defined by :c:type:`atscmh_rs_frame_ensemble`. 734 735 736.. _DTV-ATSCMH-RS-CODE-MODE-PRI: 737 738DTV_ATSCMH_RS_CODE_MODE_PRI 739--------------------------- 740 741Used only on ATSC-MH. 742 743Reed Solomon (RS) code mode (primary). 744 745The acceptable values are defined by :c:type:`atscmh_rs_code_mode`. 746 747 748.. _DTV-ATSCMH-RS-CODE-MODE-SEC: 749 750DTV_ATSCMH_RS_CODE_MODE_SEC 751--------------------------- 752 753Used only on ATSC-MH. 754 755Reed Solomon (RS) code mode (secondary). 756 757The acceptable values are defined by :c:type:`atscmh_rs_code_mode`. 758 759 760.. _DTV-ATSCMH-SCCC-BLOCK-MODE: 761 762DTV_ATSCMH_SCCC_BLOCK_MODE 763-------------------------- 764 765Used only on ATSC-MH. 766 767Series Concatenated Convolutional Code Block Mode. 768 769The acceptable values are defined by :c:type:`atscmh_sccc_block_mode`. 770 771 772.. _DTV-ATSCMH-SCCC-CODE-MODE-A: 773 774DTV_ATSCMH_SCCC_CODE_MODE_A 775--------------------------- 776 777Used only on ATSC-MH. 778 779Series Concatenated Convolutional Code Rate. 780 781The acceptable values are defined by :c:type:`atscmh_sccc_code_mode`. 782 783.. _DTV-ATSCMH-SCCC-CODE-MODE-B: 784 785DTV_ATSCMH_SCCC_CODE_MODE_B 786--------------------------- 787 788Used only on ATSC-MH. 789 790Series Concatenated Convolutional Code Rate. 791 792Possible values are the same as documented on enum 793:c:type:`atscmh_sccc_code_mode`. 794 795 796.. _DTV-ATSCMH-SCCC-CODE-MODE-C: 797 798DTV_ATSCMH_SCCC_CODE_MODE_C 799--------------------------- 800 801Used only on ATSC-MH. 802 803Series Concatenated Convolutional Code Rate. 804 805Possible values are the same as documented on enum 806:c:type:`atscmh_sccc_code_mode`. 807 808 809.. _DTV-ATSCMH-SCCC-CODE-MODE-D: 810 811DTV_ATSCMH_SCCC_CODE_MODE_D 812--------------------------- 813 814Used only on ATSC-MH. 815 816Series Concatenated Convolutional Code Rate. 817 818Possible values are the same as documented on enum 819:c:type:`atscmh_sccc_code_mode`. 820 821 822.. _DTV-API-VERSION: 823 824DTV_API_VERSION 825=============== 826 827Returns the major/minor version of the Digital TV API 828 829 830.. _DTV-CODE-RATE-HP: 831 832DTV_CODE_RATE_HP 833================ 834 835Used on terrestrial transmissions. 836 837The acceptable values are defined by :c:type:`fe_transmit_mode`. 838 839 840.. _DTV-CODE-RATE-LP: 841 842DTV_CODE_RATE_LP 843================ 844 845Used on terrestrial transmissions. 846 847The acceptable values are defined by :c:type:`fe_transmit_mode`. 848 849 850.. _DTV-GUARD-INTERVAL: 851 852DTV_GUARD_INTERVAL 853================== 854 855The acceptable values are defined by :c:type:`fe_guard_interval`. 856 857.. note:: 858 859 #. If ``DTV_GUARD_INTERVAL`` is set the ``GUARD_INTERVAL_AUTO`` the 860 hardware will try to find the correct guard interval (if capable) and 861 will use TMCC to fill in the missing parameters. 862 #. Interval ``GUARD_INTERVAL_1_64`` is used only for DVB-C2. 863 #. Interval ``GUARD_INTERVAL_1_128`` is used for both DVB-C2 and DVB_T2. 864 #. Intervals ``GUARD_INTERVAL_19_128`` and ``GUARD_INTERVAL_19_256`` are 865 used only for DVB-T2. 866 #. Intervals ``GUARD_INTERVAL_PN420``, ``GUARD_INTERVAL_PN595`` and 867 ``GUARD_INTERVAL_PN945`` are used only for DMTB at the present. 868 On such standard, only those intervals and ``GUARD_INTERVAL_AUTO`` 869 are valid. 870 871.. _DTV-TRANSMISSION-MODE: 872 873DTV_TRANSMISSION_MODE 874===================== 875 876 877Used only on OFTM-based standards, e. g. DVB-T/T2, ISDB-T, DTMB. 878 879Specifies the FFT size (with corresponds to the approximate number of 880carriers) used by the standard. 881 882The acceptable values are defined by :c:type:`fe_transmit_mode`. 883 884.. note:: 885 886 #. ISDB-T supports three carrier/symbol-size: 8K, 4K, 2K. It is called 887 **mode** on such standard, and are numbered from 1 to 3: 888 889 ==== ======== ======================== 890 Mode FFT size Transmission mode 891 ==== ======== ======================== 892 1 2K ``TRANSMISSION_MODE_2K`` 893 2 4K ``TRANSMISSION_MODE_4K`` 894 3 8K ``TRANSMISSION_MODE_8K`` 895 ==== ======== ======================== 896 897 #. If ``DTV_TRANSMISSION_MODE`` is set the ``TRANSMISSION_MODE_AUTO`` 898 the hardware will try to find the correct FFT-size (if capable) and 899 will use TMCC to fill in the missing parameters. 900 901 #. DVB-T specifies 2K and 8K as valid sizes. 902 903 #. DVB-T2 specifies 1K, 2K, 4K, 8K, 16K and 32K. 904 905 #. DTMB specifies C1 and C3780. 906 907 908.. _DTV-HIERARCHY: 909 910DTV_HIERARCHY 911============= 912 913Used only on DVB-T and DVB-T2. 914 915Frontend hierarchy. 916 917The acceptable values are defined by :c:type:`fe_hierarchy`. 918 919 920.. _DTV-STREAM-ID: 921 922DTV_STREAM_ID 923============= 924 925Used on DVB-C2, DVB-S2, DVB-T2 and ISDB-S. 926 927DVB-C2, DVB-S2, DVB-T2 and ISDB-S support the transmission of several 928streams on a single transport stream. This property enables the digital 929TV driver to handle substream filtering, when supported by the hardware. 930By default, substream filtering is disabled. 931 932For DVB-C2, DVB-S2 and DVB-T2, the valid substream id range is from 0 to 933255. 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