1 /* $OpenBSD: pt2254a.h,v 1.1 2002/04/25 04:56:59 mickey Exp $ */ 2 /* 3 * Copyright (c) 2002 Vladimir Popov <jumbo@narod.ru>. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 18 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 20 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 21 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 22 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 23 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 /* 26 * Princeton Technology Corp.'s Electronic Volume Controller IC PT2254A 27 * http://www.princeton.com.tw 28 * 29 * PT2254A is an electronic volume controller IC utilizing CMOS Technology 30 * specially designed for use in audio equipment. It has two built-in 31 * channels making it highly suitable for mono and stereo sound applications. 32 * Through the specially designated signals that are applied externally to 33 * the data, clock and strobe input pins, PT2254A can control attenuation 34 * and channel balance. 35 */ 36 37 #ifndef _PT2254A_H_ 38 #define _PT2254A_H_ 39 40 #define PT2254A_MAX_ATTENUATION 68 41 #define PT2254A_ATTENUATION_STEPS 35 42 43 #define PT2254A_REGISTER_LENGTH 18 44 45 #define PT2254A_ATTENUATION_MAJOR_0dB (1 << 0) 46 #define PT2254A_ATTENUATION_MAJOR_10dB (1 << 1) 47 #define PT2254A_ATTENUATION_MAJOR_20dB (1 << 2) 48 #define PT2254A_ATTENUATION_MAJOR_30dB (1 << 3) 49 #define PT2254A_ATTENUATION_MAJOR_40dB (1 << 4) 50 #define PT2254A_ATTENUATION_MAJOR_50dB (1 << 5) 51 #define PT2254A_ATTENUATION_MAJOR_60dB (1 << 6) 52 #define PT2254A_ATTENUATION_MAJOR(x) (1 << x) 53 54 #define PT2254A_ATTENUATION_MINOR_0dB (1 << 7) 55 #define PT2254A_ATTENUATION_MINOR_2dB (1 << 8 56 #define PT2254A_ATTENUATION_MINOR_4dB (1 << 9) 57 #define PT2254A_ATTENUATION_MINOR_6dB (1 << 10) 58 #define PT2254A_ATTENUATION_MINOR_8dB (1 << 11) 59 #define PT2254A_ATTENUATION_MINOR(x) (1 << (7 + x / 2)) 60 61 #define PT2254A_EMPTY_BIT (0 << 12) 62 63 #define PT2254A_BOTH_CHANNELS (3 << 13) 64 #define PT2254A_LEFT_CHANNEL (1 << 13) 65 #define PT2254A_RIGHT_CHANNEL (1 << 14) 66 67 #define PT2254A_ZERO_PADDING (0 << 15) 68 69 #define USE_CHANNEL 1 70 71 u_int32_t pt2254a_encode_volume(u_int8_t *, u_int8_t); 72 u_int32_t pt2254a_compose_register(u_int32_t, u_int32_t, int, int); 73 74 #endif /* _PT2254A_H_ */ 75