Mohsen Samadani / Mbed 2 deprecated Algorithm-testing

Code for measuring the signal with a specified length and sampling rate, and saving it on a SD card.

Dependencies:   EALib I2S mbed

Audio/TestAudio.cpp@2:8c5b6522139f, 2017-10-05 (annotated)

Committer:
msamadani
Date:
Thu Oct 05 17:44:39 2017 +0000
Revision:
2:8c5b6522139f
Parent:
0:c05b00be2229 
A version of the code that initializes the SD RAM, activates the codec, measures the signal and saves the signal onto the SD Card.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
msamadani 0:c05b00be2229 1 /*
msamadani 0:c05b00be2229 2 * Copyright 2013 Embedded Artists AB
msamadani 0:c05b00be2229 3 *
msamadani 0:c05b00be2229 4 * Licensed under the Apache License, Version 2.0 (the "License");
msamadani 0:c05b00be2229 5 * you may not use this file except in compliance with the License.
msamadani 0:c05b00be2229 6 * You may obtain a copy of the License at
msamadani 0:c05b00be2229 7 *
msamadani 0:c05b00be2229 8 * http://www.apache.org/licenses/LICENSE-2.0
msamadani 0:c05b00be2229 9 *
msamadani 0:c05b00be2229 10 * Unless required by applicable law or agreed to in writing, software
msamadani 0:c05b00be2229 11 * distributed under the License is distributed on an "AS IS" BASIS,
msamadani 0:c05b00be2229 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
msamadani 0:c05b00be2229 13 * See the License for the specific language governing permissions and
msamadani 0:c05b00be2229 14 * limitations under the License.
msamadani 0:c05b00be2229 15 */
msamadani 0:c05b00be2229 16
msamadani 0:c05b00be2229 17 /******************************************************************************
msamadani 0:c05b00be2229 18 * Includes
msamadani 0:c05b00be2229 19 *****************************************************************************/
msamadani 0:c05b00be2229 20 //#define SOUND_8KHZ
msamadani 0:c05b00be2229 21
msamadani 0:c05b00be2229 22 #include "mbed.h"
msamadani 0:c05b00be2229 23 #include "TestAudio.h"
msamadani 0:c05b00be2229 24 #include "WM8731.h"
msamadani 0:c05b00be2229 25 #include "I2S.h"
msamadani 0:c05b00be2229 26 //#include "sound.h"
msamadani 0:c05b00be2229 27
msamadani 0:c05b00be2229 28
msamadani 0:c05b00be2229 29 /******************************************************************************
msamadani 0:c05b00be2229 30 * Defines and typedefs
msamadani 0:c05b00be2229 31 *****************************************************************************/
msamadani 0:c05b00be2229 32
msamadani 0:c05b00be2229 33 #define SAMPLERATE 32000
msamadani 0:c05b00be2229 34
msamadani 0:c05b00be2229 35
msamadani 0:c05b00be2229 36 /******************************************************************************
msamadani 0:c05b00be2229 37 * Private Functions
msamadani 0:c05b00be2229 38 *****************************************************************************/
msamadani 0:c05b00be2229 39
msamadani 0:c05b00be2229 40 void TestAudio::echo(void) {
msamadani 0:c05b00be2229 41 int to_read = _i2sRx.fifo_points(); //Find out how many stereo samples to read
msamadani 0:c05b00be2229 42 //printf("%d\n\n",to_read);
msamadani 0:c05b00be2229 43
msamadani 0:c05b00be2229 44 //Read 'to_read' number of stereo samples.
msamadani 0:c05b00be2229 45 _i2sRx.read(_rxBuf, to_read);
msamadani 0:c05b00be2229 46 //printf("%d\n\n",_rxBuf);
msamadani 0:c05b00be2229 47
msamadani 0:c05b00be2229 48 //Loop through all stereo samples
msamadani 0:c05b00be2229 49 for(int i = 0; i < to_read; i+=2) {
msamadani 0:c05b00be2229 50 //printf("%d\n\n",i);
msamadani 0:c05b00be2229 51
msamadani 0:c05b00be2229 52
msamadani 0:c05b00be2229 53 //Only fill echo buffer with right side samples, i.e., ignore rxBuf[i+1] content
msamadani 0:c05b00be2229 54 _echoBuf[_echoBufPtr] = _rxBuf[i];
msamadani 0:c05b00be2229 55 //printf("%d\n\n",_echoBuf[_echoBufPtr]);
msamadani 0:c05b00be2229 56 //Increment echo buffer write pointer and check for wrap-around
msamadani 0:c05b00be2229 57 _echoBufPtr++;
msamadani 0:c05b00be2229 58 if (_echoBufPtr >= ECHOLENGTH)
msamadani 0:c05b00be2229 59 {
msamadani 0:c05b00be2229 60 _echoBufPtr = 0;
msamadani 0:c05b00be2229 61 }
msamadani 0:c05b00be2229 62 }
msamadani 0:c05b00be2229 63
msamadani 0:c05b00be2229 64 //Write samples to output/codec
msamadani 0:c05b00be2229 65 _i2sTx.write(_txBuf, to_read);
msamadani 0:c05b00be2229 66 // printf("%d\n\n",sizeof(_txBuf));
msamadani 0:c05b00be2229 67 }
msamadani 0:c05b00be2229 68
msamadani 0:c05b00be2229 69 /******************************************************************************
msamadani 0:c05b00be2229 70 * Public Functions
msamadani 0:c05b00be2229 71 *****************************************************************************/
msamadani 0:c05b00be2229 72
msamadani 0:c05b00be2229 73 /*
msamadani 0:c05b00be2229 74 Prerequisites:
msamadani 0:c05b00be2229 75
msamadani 0:c05b00be2229 76 - For this test to work jumpers JP8 and JP9 on the LPC4088 Experiment Base Board
msamadani 0:c05b00be2229 77 must both be in positions 1-2
msamadani 0:c05b00be2229 78
msamadani 0:c05b00be2229 79 - MIC cable, Line OUT, Headphone...
msamadani 0:c05b00be2229 80 */
msamadani 0:c05b00be2229 81
msamadani 0:c05b00be2229 82 TestAudio::TestAudio() : _codec(P0_27, P0_28), _i2sTx(I2S_TRANSMIT, p11, p12, p13),
msamadani 0:c05b00be2229 83 _i2sRx(I2S_RECEIVE, p14, p33, p34),_aIn(p15),_waveIdx(0),_echoBufPtr(0) {
msamadani 0:c05b00be2229 84 }
msamadani 0:c05b00be2229 85
msamadani 0:c05b00be2229 86 bool TestAudio::runTest() {
msamadani 0:c05b00be2229 87 printf("Testing audio... Exit by pressing joystick up\n");
msamadani 0:c05b00be2229 88 printf("Joystick down = play short wave-file. Joystick right/left = turn microphone boost on/off\n");
msamadani 0:c05b00be2229 89
msamadani 0:c05b00be2229 90 // joystick used for audio selection
msamadani 0:c05b00be2229 91 DigitalIn up(p32);
msamadani 0:c05b00be2229 92 DigitalIn down(p38);
msamadani 0:c05b00be2229 93 DigitalIn left(p39);
msamadani 0:c05b00be2229 94 DigitalIn right(p37);
msamadani 0:c05b00be2229 95
msamadani 0:c05b00be2229 96 for(int i=0; i<ECHOLENGTH; i++)
msamadani 0:c05b00be2229 97 _echoBuf[i] = 0;
msamadani 0:c05b00be2229 98
msamadani 0:c05b00be2229 99 _codec.power(true);
msamadani 0:c05b00be2229 100 _codec.frequency(SAMPLERATE);
msamadani 0:c05b00be2229 101 _codec.wordsize(16);
msamadani 0:c05b00be2229 102 _codec.master(true);
msamadani 0:c05b00be2229 103 _codec.headphone_volume(0.1);
msamadani 0:c05b00be2229 104 _codec.input_select(WM8731_MIC);
msamadani 0:c05b00be2229 105 _codec.microphone_boost(true);
msamadani 0:c05b00be2229 106 _codec.input_mute(false);
msamadani 0:c05b00be2229 107 _codec.output_mute(false);
msamadani 0:c05b00be2229 108 _codec.input_power(true);
msamadani 0:c05b00be2229 109 _codec.output_power(true);
msamadani 0:c05b00be2229 110 _codec.linein_volume(0.7);
msamadani 0:c05b00be2229 111 _codec.bypass(true);
msamadani 0:c05b00be2229 112 _codec.start();
msamadani 0:c05b00be2229 113
msamadani 0:c05b00be2229 114 _i2sRx.frequency(SAMPLERATE);
msamadani 0:c05b00be2229 115 _i2sRx.wordsize(16);
msamadani 0:c05b00be2229 116 _i2sRx.stereomono(I2S_MONO);
msamadani 0:c05b00be2229 117 _i2sRx.masterslave(I2S_SLAVE);
msamadani 0:c05b00be2229 118 _i2sRx.attach(this, &TestAudio::echo);
msamadani 0:c05b00be2229 119 _i2sRx.set_interrupt_fifo_level(1);
msamadani 0:c05b00be2229 120 _echoBufPtr = 0;
msamadani 0:c05b00be2229 121 _waveIdx = 0;
msamadani 0:c05b00be2229 122 _i2sRx.start();
msamadani 0:c05b00be2229 123
msamadani 0:c05b00be2229 124 _i2sTx.frequency(SAMPLERATE);
msamadani 0:c05b00be2229 125 _i2sTx.wordsize(16);
msamadani 0:c05b00be2229 126 _i2sTx.stereomono(I2S_MONO);
msamadani 0:c05b00be2229 127 _i2sTx.masterslave(I2S_SLAVE);
msamadani 0:c05b00be2229 128 _i2sTx.start();
msamadani 0:c05b00be2229 129
msamadani 0:c05b00be2229 130 int lastVol = -1000; // value not important
msamadani 0:c05b00be2229 131 do
msamadani 0:c05b00be2229 132 {
msamadani 0:c05b00be2229 133 //check if joystick-down pressed = play wave-file
msamadani 0:c05b00be2229 134 if ((down.read() == 0) && (_waveIdx == 0))
msamadani 0:c05b00be2229 135 _waveIdx = 2;
msamadani 0:c05b00be2229 136
msamadani 0:c05b00be2229 137 //check if joystick-left pressed = turn off microphone boost
msamadani 0:c05b00be2229 138 if (left.read() == 0)
msamadani 0:c05b00be2229 139 {
msamadani 0:c05b00be2229 140 _codec.input_mute(true);
msamadani 0:c05b00be2229 141 wait(0.2);
msamadani 0:c05b00be2229 142 _codec.microphone_boost(false);
msamadani 0:c05b00be2229 143 wait(0.2);
msamadani 0:c05b00be2229 144 _codec.input_mute(false);
msamadani 0:c05b00be2229 145 }
msamadani 0:c05b00be2229 146
msamadani 0:c05b00be2229 147 //check if joystick-right pressed = turn on microphone boost
msamadani 0:c05b00be2229 148 if (right.read() == 0)
msamadani 0:c05b00be2229 149 {
msamadani 0:c05b00be2229 150 _codec.input_mute(true);
msamadani 0:c05b00be2229 151 wait(0.2);
msamadani 0:c05b00be2229 152 _codec.microphone_boost(true);
msamadani 0:c05b00be2229 153 wait(0.2);
msamadani 0:c05b00be2229 154 _codec.input_mute(false);
msamadani 0:c05b00be2229 155 }
msamadani 0:c05b00be2229 156
msamadani 0:c05b00be2229 157
msamadani 0:c05b00be2229 158 //attempt to filter out the small variations in analog values and
msamadani 0:c05b00be2229 159 //only update volume when a "large enough" change is detected.
msamadani 0:c05b00be2229 160 float v = _aIn;
msamadani 0:c05b00be2229 161 int val = ((int)(v*1000))>>2;
msamadani 0:c05b00be2229 162 if (val != lastVol) {
msamadani 0:c05b00be2229 163 _codec.headphone_volume(v);
msamadani 0:c05b00be2229 164 lastVol = val;
msamadani 0:c05b00be2229 165 }
msamadani 0:c05b00be2229 166
msamadani 0:c05b00be2229 167
msamadani 0:c05b00be2229 168 //_codec.headphone_volume(_aIn);
msamadani 0:c05b00be2229 169 wait(0.25);
msamadani 0:c05b00be2229 170 } while (up.read() != 0);
msamadani 0:c05b00be2229 171
msamadani 0:c05b00be2229 172 _codec.power(false);
msamadani 0:c05b00be2229 173 return true;
msamadani 0:c05b00be2229 174 }
msamadani 0:c05b00be2229 175
msamadani 0:c05b00be2229 176