Neil Thiessen / MAX9723

A feature complete driver for the MAX9723 headphone amplifier from Maxim.

Dependents:   MAX9723_HelloWorld

MAX9723.cpp@0:99db25d6f38d, 2014-05-30 (annotated)

Committer:
neilt6
Date:
Fri May 30 19:46:37 2014 +0000
Revision:
0:99db25d6f38d
Initial commit

Who changed what in which revision?

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neilt6 0:99db25d6f38d 1 /* MAX9723 Driver Library
neilt6 0:99db25d6f38d 2 * Copyright (c) 2014 Neil Thiessen
neilt6 0:99db25d6f38d 3 *
neilt6 0:99db25d6f38d 4 * Licensed under the Apache License, Version 2.0 (the "License");
neilt6 0:99db25d6f38d 5 * you may not use this file except in compliance with the License.
neilt6 0:99db25d6f38d 6 * You may obtain a copy of the License at
neilt6 0:99db25d6f38d 7 *
neilt6 0:99db25d6f38d 8 * http://www.apache.org/licenses/LICENSE-2.0
neilt6 0:99db25d6f38d 9 *
neilt6 0:99db25d6f38d 10 * Unless required by applicable law or agreed to in writing, software
neilt6 0:99db25d6f38d 11 * distributed under the License is distributed on an "AS IS" BASIS,
neilt6 0:99db25d6f38d 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
neilt6 0:99db25d6f38d 13 * See the License for the specific language governing permissions and
neilt6 0:99db25d6f38d 14 * limitations under the License.
neilt6 0:99db25d6f38d 15 */
neilt6 0:99db25d6f38d 16
neilt6 0:99db25d6f38d 17 #include "MAX9723.h"
neilt6 0:99db25d6f38d 18
neilt6 0:99db25d6f38d 19 MAX9723::MAX9723(PinName sda, PinName scl, Address addr, int hz) : m_I2C(sda, scl), m_ADDR((int)addr)
neilt6 0:99db25d6f38d 20 {
neilt6 0:99db25d6f38d 21 //Initialize the member variables
neilt6 0:99db25d6f38d 22 m_AmpValue = 255;
neilt6 0:99db25d6f38d 23
neilt6 0:99db25d6f38d 24 //Set the I2C bus frequency
neilt6 0:99db25d6f38d 25 m_I2C.frequency(hz);
neilt6 0:99db25d6f38d 26 }
neilt6 0:99db25d6f38d 27
neilt6 0:99db25d6f38d 28 bool MAX9723::open()
neilt6 0:99db25d6f38d 29 {
neilt6 0:99db25d6f38d 30 //Probe for the MAX9723 using a Zero Length Transfer
neilt6 0:99db25d6f38d 31 if (!m_I2C.write(m_ADDR, NULL, 0)) {
neilt6 0:99db25d6f38d 32 //Make sure the amp value variable is set to the default register value
neilt6 0:99db25d6f38d 33 m_AmpValue = 255;
neilt6 0:99db25d6f38d 34
neilt6 0:99db25d6f38d 35 //Write the default register value
neilt6 0:99db25d6f38d 36 m_I2C.write(m_ADDR, &m_AmpValue, 1);
neilt6 0:99db25d6f38d 37
neilt6 0:99db25d6f38d 38 //Return success
neilt6 0:99db25d6f38d 39 return true;
neilt6 0:99db25d6f38d 40 } else {
neilt6 0:99db25d6f38d 41 //Return failure
neilt6 0:99db25d6f38d 42 return false;
neilt6 0:99db25d6f38d 43 }
neilt6 0:99db25d6f38d 44 }
neilt6 0:99db25d6f38d 45
neilt6 0:99db25d6f38d 46 bool MAX9723::enabled()
neilt6 0:99db25d6f38d 47 {
neilt6 0:99db25d6f38d 48 //Return the status of the SHUTDOWN bit
neilt6 0:99db25d6f38d 49 return (m_AmpValue & (1 << 7));
neilt6 0:99db25d6f38d 50 }
neilt6 0:99db25d6f38d 51
neilt6 0:99db25d6f38d 52 void MAX9723::enabled(bool enabled)
neilt6 0:99db25d6f38d 53 {
neilt6 0:99db25d6f38d 54 //Set or clear the SHUTDOWN bit
neilt6 0:99db25d6f38d 55 if (enabled)
neilt6 0:99db25d6f38d 56 m_AmpValue |= (1 << 7);
neilt6 0:99db25d6f38d 57 else
neilt6 0:99db25d6f38d 58 m_AmpValue &= ~(1 << 7);
neilt6 0:99db25d6f38d 59
neilt6 0:99db25d6f38d 60 //Write the value back out
neilt6 0:99db25d6f38d 61 m_I2C.write(m_ADDR, &m_AmpValue, 1);
neilt6 0:99db25d6f38d 62 }
neilt6 0:99db25d6f38d 63
neilt6 0:99db25d6f38d 64 bool MAX9723::bassMax()
neilt6 0:99db25d6f38d 65 {
neilt6 0:99db25d6f38d 66 //Return the status of the BassMax ENABLE bit
neilt6 0:99db25d6f38d 67 return (m_AmpValue & (1 << 6));
neilt6 0:99db25d6f38d 68 }
neilt6 0:99db25d6f38d 69
neilt6 0:99db25d6f38d 70 void MAX9723::bassMax(bool enabled)
neilt6 0:99db25d6f38d 71 {
neilt6 0:99db25d6f38d 72 //Set or clear the BassMax ENABLE bit
neilt6 0:99db25d6f38d 73 if (enabled)
neilt6 0:99db25d6f38d 74 m_AmpValue |= (1 << 6);
neilt6 0:99db25d6f38d 75 else
neilt6 0:99db25d6f38d 76 m_AmpValue &= ~(1 << 6);
neilt6 0:99db25d6f38d 77
neilt6 0:99db25d6f38d 78 //Write the value back out
neilt6 0:99db25d6f38d 79 m_I2C.write(m_ADDR, &m_AmpValue, 1);
neilt6 0:99db25d6f38d 80 }
neilt6 0:99db25d6f38d 81
neilt6 0:99db25d6f38d 82 bool MAX9723::maxGain()
neilt6 0:99db25d6f38d 83 {
neilt6 0:99db25d6f38d 84 //Return the status of the MAXIMUM GAIN bit
neilt6 0:99db25d6f38d 85 return (m_AmpValue & (1 << 5));
neilt6 0:99db25d6f38d 86 }
neilt6 0:99db25d6f38d 87
neilt6 0:99db25d6f38d 88 void MAX9723::maxGain(bool max)
neilt6 0:99db25d6f38d 89 {
neilt6 0:99db25d6f38d 90 //Set or clear the MAXIMUM GAIN bit
neilt6 0:99db25d6f38d 91 if (max)
neilt6 0:99db25d6f38d 92 m_AmpValue |= (1 << 5);
neilt6 0:99db25d6f38d 93 else
neilt6 0:99db25d6f38d 94 m_AmpValue &= ~(1 << 5);
neilt6 0:99db25d6f38d 95
neilt6 0:99db25d6f38d 96 //Write the value back out
neilt6 0:99db25d6f38d 97 m_I2C.write(m_ADDR, &m_AmpValue, 1);
neilt6 0:99db25d6f38d 98 }
neilt6 0:99db25d6f38d 99
neilt6 0:99db25d6f38d 100 float MAX9723::volume()
neilt6 0:99db25d6f38d 101 {
neilt6 0:99db25d6f38d 102 //Return the bottom 5 bits
neilt6 0:99db25d6f38d 103 return (m_AmpValue & 0x1F) / 31.0;
neilt6 0:99db25d6f38d 104 }
neilt6 0:99db25d6f38d 105
neilt6 0:99db25d6f38d 106 void MAX9723::volume(float volume)
neilt6 0:99db25d6f38d 107 {
neilt6 0:99db25d6f38d 108 //Mask off the old volume
neilt6 0:99db25d6f38d 109 m_AmpValue &= 0xE0;
neilt6 0:99db25d6f38d 110
neilt6 0:99db25d6f38d 111 //Set the new volume
neilt6 0:99db25d6f38d 112 m_AmpValue |= (char)(volume * 31.0);
neilt6 0:99db25d6f38d 113
neilt6 0:99db25d6f38d 114 //Write the value back out
neilt6 0:99db25d6f38d 115 m_I2C.write(m_ADDR, &m_AmpValue, 1);
neilt6 0:99db25d6f38d 116 }
neilt6 0:99db25d6f38d 117
neilt6 0:99db25d6f38d 118 #ifdef MBED_OPERATORS
neilt6 0:99db25d6f38d 119 MAX9723::operator float()
neilt6 0:99db25d6f38d 120 {
neilt6 0:99db25d6f38d 121 //Return the current volume
neilt6 0:99db25d6f38d 122 return volume();
neilt6 0:99db25d6f38d 123 }
neilt6 0:99db25d6f38d 124
neilt6 0:99db25d6f38d 125 MAX9723& MAX9723::operator=(float value)
neilt6 0:99db25d6f38d 126 {
neilt6 0:99db25d6f38d 127 //Set the volume
neilt6 0:99db25d6f38d 128 volume(value);
neilt6 0:99db25d6f38d 129 return *this;
neilt6 0:99db25d6f38d 130 }
neilt6 0:99db25d6f38d 131 #endif