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