//GiGaHeRz's SPU2 Driver //Copyright (c) 2003-2008, David Quintana // //This library is free software; you can redistribute it and/or //modify it under the terms of the GNU Lesser General Public //License as published by the Free Software Foundation; either //version 2.1 of the License, or (at your option) any later version. // //This library is distributed in the hope that it will be useful, //but WITHOUT ANY WARRANTY; without even the implied warranty of //MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU //Lesser General Public License for more details. // //You should have received a copy of the GNU Lesser General Public //License along with this library; if not, write to the Free Software //Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA // #pragma once #ifndef u32 typedef unsigned int u32; #endif /* Preamble cell-order cell-order (last cell "0") (last cell "1") ---------------------------------------------- "B" 11101000 00010111 "M" 11100010 00011101 "W" 11100100 00011011 Only the lower 4 bits are used. Preamble B: Marks a word containing data for channel A (left) at the start of the data-block. Preamble M: Marks a word with data for channel A that isn't at the start of the data-block. Preamble W: Marks a word containing data for channel B. (right, for stereo). When using more than 2 channels, this could also be any other channel (except for A). bits meaning ---------------------------------------------------------- 0-3 Preamble (see above; special structure) 4-7 Auxillary-audio-databits 8-27 Sample (A 24-bit sample can be used (using bits 4-27). A CD-player uses only 16 bits, so only bits 13 (LSB) to 27 (MSB) are used. Bits 4-12 are set to 0). 28 Validity (When this bit is set, the sample should not be used by the receiver. A CD-player uses the 'error-flag' to set this bit). 29 Subcode-data 30 Channel-status-information 31 Parity (bit 0-3 are not included) */ typedef struct _subframe { u32 preamble:4; u32 aux_data:4; u32 snd_data:20; u32 validity:1; u32 subcode:1; u32 chstatus:1; u32 parity:1; } subframe; /* bit meaning ------------------------------------------------------------- 0-3 controlbits: bit 0: 0 (is set to 1 during 4 channel transmission) bit 1: 0=Digital audio, 1=Non-audio (reserved to be 0 on old S/PDIF specs) bit 2: copy-protection. Copying is allowed when this bit is set. bit 3: is set when pre-emphasis is used. 4-7 0 (reserved) 9-15 catagory-code: 0 = common 2-channel format 1 = 2-channel CD-format (set by a CD-player when a subcode is transmitted) 2 = 2-channel PCM-encoder-decoder format others are not used 19-191 0 (reserved) */ typedef struct _chstatus { u8 ctrlbits:4; u8 reservd1:4; u8 category; u8 reservd2[22]; } chstatus: