1 .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2 3 .. _fe_property_parameters: 4 5 ****************************** 6 Digital TV property parameters 7 ****************************** 8 9 There are several different Digital TV parameters that can be used by 10 :ref:`FE_SET_PROPERTY and FE_GET_PROPERTY ioctls<FE_GET_PROPERTY>`. 11 This section describes each of them. Please notice, however, that only 12 a subset of them are needed to setup a frontend. 13 14 15 .. _DTV-UNDEFINED: 16 17 DTV_UNDEFINED 18 ============= 19 20 Used internally. A GET/SET operation for it won't change or return 21 anything. 22 23 24 .. _DTV-TUNE: 25 26 DTV_TUNE 27 ======== 28 29 Interpret the cache of data, build either a traditional frontend 30 tunerequest so we can pass validation in the ``FE_SET_FRONTEND`` ioctl. 31 32 33 .. _DTV-CLEAR: 34 35 DTV_CLEAR 36 ========= 37 38 Reset a cache of data specific to the frontend here. This does not 39 effect hardware. 40 41 42 .. _DTV-FREQUENCY: 43 44 DTV_FREQUENCY 45 ============= 46 47 Frequency 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 71 DTV_MODULATION 72 ============== 73 74 Specifies the frontend modulation type for delivery systems that 75 supports more multiple modulations. 76 77 The modulation can be one of the types defined by enum :c:type:`fe_modulation`. 78 79 Most of the digital TV standards offers more than one possible 80 modulation type. 81 82 The table below presents a summary of the types of modulation types 83 supported by each delivery system, as currently defined by specs. 84 85 ======================= ======================================================= 86 Standard Modulation types 87 ======================= ======================================================= 88 ATSC (version 1) 8-VSB and 16-VSB. 89 DMTB 4-QAM, 16-QAM, 32-QAM, 64-QAM and 4-QAM-NR. 90 DVB-C Annex A/C 16-QAM, 32-QAM, 64-QAM and 256-QAM. 91 DVB-C Annex B 64-QAM. 92 DVB-C2 QPSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM and 4096-QAM. 93 DVB-T QPSK, 16-QAM and 64-QAM. 94 DVB-T2 QPSK, 16-QAM, 64-QAM and 256-QAM. 95 DVB-S No need to set. It supports only QPSK. 96 DVB-S2 QPSK, 8-PSK, 16-APSK and 32-APSK. 97 DVB-S2X 8-APSK-L, 16-APSK-L, 32-APSK-L, 64-APSK and 64-APSK-L. 98 ISDB-T QPSK, DQPSK, 16-QAM and 64-QAM. 99 ISDB-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: 113 114 DTV_BANDWIDTH_HZ 115 ================ 116 117 Bandwidth for the channel, in HZ. 118 119 Should be set only for terrestrial delivery systems. 120 121 Possible values: ``1712000``, ``5000000``, ``6000000``, ``7000000``, 122 ``8000000``, ``10000000``. 123 124 ======================= ======================================================= 125 Terrestrial Standard Possible values for bandwidth 126 ======================= ======================================================= 127 ATSC (version 1) No need to set. It is always 6MHz. 128 DMTB No need to set. It is always 8MHz. 129 DVB-T 6MHz, 7MHz and 8MHz. 130 DVB-T2 1.172 MHz, 5MHz, 6MHz, 7MHz, 8MHz and 10MHz 131 ISDB-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: 158 159 DTV_INVERSION 160 ============= 161 162 Specifies if the frontend should do spectral inversion or not. 163 164 The acceptable values are defined by :c:type:`fe_spectral_inversion`. 165 166 167 .. _DTV-DISEQC-MASTER: 168 169 DTV_DISEQC_MASTER 170 ================= 171 172 Currently not implemented. 173 174 175 .. _DTV-SYMBOL-RATE: 176 177 DTV_SYMBOL_RATE 178 =============== 179 180 Used on cable and satellite delivery systems. 181 182 Digital TV symbol rate, in bauds (symbols/second). 183 184 185 .. _DTV-INNER-FEC: 186 187 DTV_INNER_FEC 188 ============= 189 190 Used on cable and satellite delivery systems. 191 192 The acceptable values are defined by :c:type:`fe_code_rate`. 193 194 195 .. _DTV-VOLTAGE: 196 197 DTV_VOLTAGE 198 =========== 199 200 Used on satellite delivery systems. 201 202 The voltage is usually used with non-DiSEqC capable LNBs to switch the 203 polarzation (horizontal/vertical). When using DiSEqC epuipment this 204 voltage has to be switched consistently to the DiSEqC commands as 205 described in the DiSEqC spec. 206 207 The acceptable values are defined by :c:type:`fe_sec_voltage`. 208 209 210 .. _DTV-TONE: 211 212 DTV_TONE 213 ======== 214 215 Currently not used. 216 217 218 .. _DTV-PILOT: 219 220 DTV_PILOT 221 ========= 222 223 Used on DVB-S2. 224 225 Sets DVB-S2 pilot. 226 227 The acceptable values are defined by :c:type:`fe_pilot`. 228 229 230 .. _DTV-ROLLOFF: 231 232 DTV_ROLLOFF 233 =========== 234 235 Used on DVB-S2. 236 237 Sets DVB-S2 rolloff. 238 239 The acceptable values are defined by :c:type:`fe_rolloff`. 240 241 242 .. _DTV-DISEQC-SLAVE-REPLY: 243 244 DTV_DISEQC_SLAVE_REPLY 245 ====================== 246 247 Currently not implemented. 248 249 250 .. _DTV-FE-CAPABILITY-COUNT: 251 252 DTV_FE_CAPABILITY_COUNT 253 ======================= 254 255 Currently not implemented. 256 257 258 .. _DTV-FE-CAPABILITY: 259 260 DTV_FE_CAPABILITY 261 ================= 262 263 Currently not implemented. 264 265 266 .. _DTV-DELIVERY-SYSTEM: 267 268 DTV_DELIVERY_SYSTEM 269 =================== 270 271 Specifies the type of the delivery system. 272 273 The acceptable values are defined by :c:type:`fe_delivery_system`. 274 275 276 .. _DTV-ISDBT-PARTIAL-RECEPTION: 277 278 DTV_ISDBT_PARTIAL_RECEPTION 279 =========================== 280 281 Used only on ISDB. 282 283 If ``DTV_ISDBT_SOUND_BROADCASTING`` is '0' this bit-field represents 284 whether the channel is in partial reception mode or not. 285 286 If '1' ``DTV_ISDBT_LAYERA_*`` values are assigned to the center segment 287 and ``DTV_ISDBT_LAYERA_SEGMENT_COUNT`` has to be '1'. 288 289 If in addition ``DTV_ISDBT_SOUND_BROADCASTING`` is '1' 290 ``DTV_ISDBT_PARTIAL_RECEPTION`` represents whether this ISDB-Tsb channel 291 is consisting of one segment and layer or three segments and two layers. 292 293 Possible values: 0, 1, -1 (AUTO) 294 295 296 .. _DTV-ISDBT-SOUND-BROADCASTING: 297 298 DTV_ISDBT_SOUND_BROADCASTING 299 ============================ 300 301 Used only on ISDB. 302 303 This field represents whether the other DTV_ISDBT_*-parameters are 304 referring to an ISDB-T and an ISDB-Tsb channel. (See also 305 ``DTV_ISDBT_PARTIAL_RECEPTION``). 306 307 Possible values: 0, 1, -1 (AUTO) 308 309 310 .. _DTV-ISDBT-SB-SUBCHANNEL-ID: 311 312 DTV_ISDBT_SB_SUBCHANNEL_ID 313 ========================== 314 315 Used only on ISDB. 316 317 This 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 321 technical background needed to program a device) 322 323 An ISDB-Tsb channel (1 or 3 segments) can be broadcasted alone or in a 324 set of connected ISDB-Tsb channels. In this set of channels every 325 channel can be received independently. The number of connected ISDB-Tsb 326 segment can vary, e.g. depending on the frequency spectrum bandwidth 327 available. 328 329 Example: Assume 8 ISDB-Tsb connected segments are broadcasted. The 330 broadcaster has several possibilities to put those channels in the air: 331 Assuming a normal 13-segment ISDB-T spectrum he can align the 8 segments 332 from position 1-8 to 5-13 or anything in between. 333 334 The underlying layer of segments are subchannels: each segment is 335 consisting of several subchannels with a predefined IDs. A sub-channel 336 is used to help the demodulator to synchronize on the channel. 337 338 An ISDB-T channel is always centered over all sub-channels. As for the 339 example 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 342 sub-channel ID of the segment to be demodulated. 343 344 Possible values: 0 .. 41, -1 (AUTO) 345 346 347 .. _DTV-ISDBT-SB-SEGMENT-IDX: 348 349 DTV_ISDBT_SB_SEGMENT_IDX 350 ======================== 351 352 Used only on ISDB. 353 354 This 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 357 demodulated for an ISDB-Tsb channel where several of them are 358 transmitted in the connected manner. 359 360 Possible values: 0 .. ``DTV_ISDBT_SB_SEGMENT_COUNT`` - 1 361 362 Note: This value cannot be determined by an automatic channel search. 363 364 365 .. _DTV-ISDBT-SB-SEGMENT-COUNT: 366 367 DTV_ISDBT_SB_SEGMENT_COUNT 368 ========================== 369 370 Used only on ISDB. 371 372 This field only applies if ``DTV_ISDBT_SOUND_BROADCASTING`` is '1'. 373 374 ``DTV_ISDBT_SB_SEGMENT_COUNT`` gives the total count of connected 375 ISDB-Tsb channels. 376 377 Possible values: 1 .. 13 378 379 Note: This value cannot be determined by an automatic channel search. 380 381 382 .. _isdb-hierq-layers: 383 384 DTV-ISDBT-LAYER[A-C] parameters 385 =============================== 386 387 Used only on ISDB. 388 389 ISDB-T channels can be coded hierarchically. As opposed to DVB-T in 390 ISDB-T hierarchical layers can be decoded simultaneously. For that 391 reason a ISDB-T demodulator has 3 Viterbi and 3 Reed-Solomon decoders. 392 393 ISDB-T has 3 hierarchical layers which each can use a part of the 394 available segments. The total number of segments over all layers has to 395 13 in ISDB-T. 396 397 There are 3 parameter sets, for Layers A, B and C. 398 399 400 .. _DTV-ISDBT-LAYER-ENABLED: 401 402 DTV_ISDBT_LAYER_ENABLED 403 ----------------------- 404 405 Used only on ISDB. 406 407 Hierarchical reception in ISDB-T is achieved by enabling or disabling 408 layers in the decoding process. Setting all bits of 409 ``DTV_ISDBT_LAYER_ENABLED`` to '1' forces all layers (if applicable) to 410 be demodulated. This is the default. 411 412 If the channel is in the partial reception mode 413 (``DTV_ISDBT_PARTIAL_RECEPTION`` = 1) the central segment can be decoded 414 independently of the other 12 segments. In that mode layer A has to have 415 a ``SEGMENT_COUNT`` of 1. 416 417 In ISDB-Tsb only layer A is used, it can be 1 or 3 in ISDB-Tsb according 418 to ``DTV_ISDBT_PARTIAL_RECEPTION``. ``SEGMENT_COUNT`` must be filled 419 accordingly. 420 421 Only 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: 433 434 DTV_ISDBT_LAYER[A-C]_FEC 435 ------------------------ 436 437 Used only on ISDB. 438 439 The Forward Error Correction mechanism used by a given ISDB Layer, as 440 defined by :c:type:`fe_code_rate`. 441 442 443 Possible 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: 448 449 DTV_ISDBT_LAYER[A-C]_MODULATION 450 ------------------------------- 451 452 Used only on ISDB. 453 454 The modulation used by a given ISDB Layer, as defined by 455 :c:type:`fe_modulation`. 456 457 Possible 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: 468 469 DTV_ISDBT_LAYER[A-C]_SEGMENT_COUNT 470 ---------------------------------- 471 472 Used only on ISDB. 473 474 Possible values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1 (AUTO) 475 476 Note: 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: 559 560 DTV_ISDBT_LAYER[A-C]_TIME_INTERLEAVING 561 -------------------------------------- 562 563 Used only on ISDB. 564 565 Valid values: 0, 1, 2, 4, -1 (AUTO) 566 567 when DTV_ISDBT_SOUND_BROADCASTING is active, value 8 is also valid. 568 569 Note: The real time interleaving length depends on the mode (fft-size). 570 The values here are referring to what can be found in the 571 TMCC-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: 634 635 DTV_ATSCMH_FIC_VER 636 ------------------ 637 638 Used only on ATSC-MH. 639 640 Version number of the FIC (Fast Information Channel) signaling data. 641 642 FIC is used for relaying information to allow rapid service acquisition 643 by the receiver. 644 645 Possible values: 0, 1, 2, 3, ..., 30, 31 646 647 648 .. _DTV-ATSCMH-PARADE-ID: 649 650 DTV_ATSCMH_PARADE_ID 651 -------------------- 652 653 Used only on ATSC-MH. 654 655 Parade identification number 656 657 A parade is a collection of up to eight MH groups, conveying one or two 658 ensembles. 659 660 Possible values: 0, 1, 2, 3, ..., 126, 127 661 662 663 .. _DTV-ATSCMH-NOG: 664 665 DTV_ATSCMH_NOG 666 -------------- 667 668 Used only on ATSC-MH. 669 670 Number of MH groups per MH subframe for a designated parade. 671 672 Possible values: 1, 2, 3, 4, 5, 6, 7, 8 673 674 675 .. _DTV-ATSCMH-TNOG: 676 677 DTV_ATSCMH_TNOG 678 --------------- 679 680 Used only on ATSC-MH. 681 682 Total number of MH groups including all MH groups belonging to all MH 683 parades in one MH subframe. 684 685 Possible values: 0, 1, 2, 3, ..., 30, 31 686 687 688 .. _DTV-ATSCMH-SGN: 689 690 DTV_ATSCMH_SGN 691 -------------- 692 693 Used only on ATSC-MH. 694 695 Start group number. 696 697 Possible values: 0, 1, 2, 3, ..., 14, 15 698 699 700 .. _DTV-ATSCMH-PRC: 701 702 DTV_ATSCMH_PRC 703 -------------- 704 705 Used only on ATSC-MH. 706 707 Parade repetition cycle. 708 709 Possible values: 1, 2, 3, 4, 5, 6, 7, 8 710 711 712 .. _DTV-ATSCMH-RS-FRAME-MODE: 713 714 DTV_ATSCMH_RS_FRAME_MODE 715 ------------------------ 716 717 Used only on ATSC-MH. 718 719 Reed Solomon (RS) frame mode. 720 721 The acceptable values are defined by :c:type:`atscmh_rs_frame_mode`. 722 723 724 .. _DTV-ATSCMH-RS-FRAME-ENSEMBLE: 725 726 DTV_ATSCMH_RS_FRAME_ENSEMBLE 727 ---------------------------- 728 729 Used only on ATSC-MH. 730 731 Reed Solomon(RS) frame ensemble. 732 733 The acceptable values are defined by :c:type:`atscmh_rs_frame_ensemble`. 734 735 736 .. _DTV-ATSCMH-RS-CODE-MODE-PRI: 737 738 DTV_ATSCMH_RS_CODE_MODE_PRI 739 --------------------------- 740 741 Used only on ATSC-MH. 742 743 Reed Solomon (RS) code mode (primary). 744 745 The acceptable values are defined by :c:type:`atscmh_rs_code_mode`. 746 747 748 .. _DTV-ATSCMH-RS-CODE-MODE-SEC: 749 750 DTV_ATSCMH_RS_CODE_MODE_SEC 751 --------------------------- 752 753 Used only on ATSC-MH. 754 755 Reed Solomon (RS) code mode (secondary). 756 757 The acceptable values are defined by :c:type:`atscmh_rs_code_mode`. 758 759 760 .. _DTV-ATSCMH-SCCC-BLOCK-MODE: 761 762 DTV_ATSCMH_SCCC_BLOCK_MODE 763 -------------------------- 764 765 Used only on ATSC-MH. 766 767 Series Concatenated Convolutional Code Block Mode. 768 769 The acceptable values are defined by :c:type:`atscmh_sccc_block_mode`. 770 771 772 .. _DTV-ATSCMH-SCCC-CODE-MODE-A: 773 774 DTV_ATSCMH_SCCC_CODE_MODE_A 775 --------------------------- 776 777 Used only on ATSC-MH. 778 779 Series Concatenated Convolutional Code Rate. 780 781 The acceptable values are defined by :c:type:`atscmh_sccc_code_mode`. 782 783 .. _DTV-ATSCMH-SCCC-CODE-MODE-B: 784 785 DTV_ATSCMH_SCCC_CODE_MODE_B 786 --------------------------- 787 788 Used only on ATSC-MH. 789 790 Series Concatenated Convolutional Code Rate. 791 792 Possible values are the same as documented on enum 793 :c:type:`atscmh_sccc_code_mode`. 794 795 796 .. _DTV-ATSCMH-SCCC-CODE-MODE-C: 797 798 DTV_ATSCMH_SCCC_CODE_MODE_C 799 --------------------------- 800 801 Used only on ATSC-MH. 802 803 Series Concatenated Convolutional Code Rate. 804 805 Possible values are the same as documented on enum 806 :c:type:`atscmh_sccc_code_mode`. 807 808 809 .. _DTV-ATSCMH-SCCC-CODE-MODE-D: 810 811 DTV_ATSCMH_SCCC_CODE_MODE_D 812 --------------------------- 813 814 Used only on ATSC-MH. 815 816 Series Concatenated Convolutional Code Rate. 817 818 Possible values are the same as documented on enum 819 :c:type:`atscmh_sccc_code_mode`. 820 821 822 .. _DTV-API-VERSION: 823 824 DTV_API_VERSION 825 =============== 826 827 Returns the major/minor version of the Digital TV API 828 829 830 .. _DTV-CODE-RATE-HP: 831 832 DTV_CODE_RATE_HP 833 ================ 834 835 Used on terrestrial transmissions. 836 837 The acceptable values are defined by :c:type:`fe_transmit_mode`. 838 839 840 .. _DTV-CODE-RATE-LP: 841 842 DTV_CODE_RATE_LP 843 ================ 844 845 Used on terrestrial transmissions. 846 847 The acceptable values are defined by :c:type:`fe_transmit_mode`. 848 849 850 .. _DTV-GUARD-INTERVAL: 851 852 DTV_GUARD_INTERVAL 853 ================== 854 855 The 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: 872 873 DTV_TRANSMISSION_MODE 874 ===================== 875 876 877 Used only on OFTM-based standards, e. g. DVB-T/T2, ISDB-T, DTMB. 878 879 Specifies the FFT size (with corresponds to the approximate number of 880 carriers) used by the standard. 881 882 The 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: 909 910 DTV_HIERARCHY 911 ============= 912 913 Used only on DVB-T and DVB-T2. 914 915 Frontend hierarchy. 916 917 The acceptable values are defined by :c:type:`fe_hierarchy`. 918 919 920 .. _DTV-STREAM-ID: 921 922 DTV_STREAM_ID 923 ============= 924 925 Used on DVB-C2, DVB-S2, DVB-T2 and ISDB-S. 926 927 DVB-C2, DVB-S2, DVB-T2 and ISDB-S support the transmission of several 928 streams on a single transport stream. This property enables the digital 929 TV driver to handle substream filtering, when supported by the hardware. 930 By default, substream filtering is disabled. 931 932 For DVB-C2, DVB-S2 and DVB-T2, the valid substream id range is from 0 to 933 255. 934 935 For ISDB, the valid substream id range is from 1 to 65535. 936 937 To disable it, you should use the special macro NO_STREAM_ID_FILTER. 938 939 Note: any value outside the id range also disables filtering. 940 941 942 .. _DTV-DVBT2-PLP-ID-LEGACY: 943 944 DTV_DVBT2_PLP_ID_LEGACY 945 ======================= 946 947 Obsolete, replaced with DTV_STREAM_ID. 948 949 950 .. _DTV-ENUM-DELSYS: 951 952 DTV_ENUM_DELSYS 953 =============== 954 955 A Multi standard frontend needs to advertise the delivery systems 956 provided. Applications need to enumerate the provided delivery systems, 957 before using any other operation with the frontend. Prior to it's 958 introduction, FE_GET_INFO was used to determine a frontend type. A 959 frontend which provides more than a single delivery system, 960 FE_GET_INFO doesn't help much. Applications which intends to use a 961 multistandard frontend must enumerate the delivery systems associated 962 with it, rather than trying to use FE_GET_INFO. In the case of a 963 legacy frontend, the result is just the same as with FE_GET_INFO, but 964 in a more structured format 965 966 The acceptable values are defined by :c:type:`fe_delivery_system`. 967 968 969 .. _DTV-INTERLEAVING: 970 971 DTV_INTERLEAVING 972 ================ 973 974 Time interleaving to be used. 975 976 The acceptable values are defined by :c:type:`fe_interleaving`. 977 978 979 .. _DTV-LNA: 980 981 DTV_LNA 982 ======= 983 984 Low-noise amplifier. 985 986 Hardware might offer controllable LNA which can be set manually using 987 that parameter. Usually LNA could be found only from terrestrial devices 988 if at all. 989 990 Possible values: 0, 1, LNA_AUTO 991 992 0, LNA off 993 994 1, LNA on 995 996 use the special macro LNA_AUTO to set LNA auto 997 998 999 .. _DTV-SCRAMBLING-SEQUENCE-INDEX: 1000 1001 DTV_SCRAMBLING_SEQUENCE_INDEX 1002 ============================= 1003 1004 Used on DVB-S2. 1005 1006 This 18 bit field, when present, carries the index of the DVB-S2 physical 1007 layer scrambling sequence as defined in clause 5.5.4 of EN 302 307. 1008 There is no explicit signalling method to convey scrambling sequence index 1009 to the receiver. If S2 satellite delivery system descriptor is available 1010 it can be used to read the scrambling sequence index (EN 300 468 table 41). 1011 1012 By default, gold scrambling sequence index 0 is used. 1013 1014 The valid scrambling sequence index range is from 0 to 262142.
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