Specifications

List of figures
Figure 1 The network layers [1] ....................................................................................... 7
Figure 2 The AudioTron [3] ............................................................................................. 8
Figure 3 Functional diagram of the AudioTron [3] .......................................................... 9
Figure 4 Motorola SimpleFi [4.]....................................................................................... 9
Figure 5 Overall design layout........................................................................................ 12
Figure 6 Ethernut development kit [9]............................................................................ 16
Figure 7 The MP3 decoder board [19]............................................................................ 19
Figure 8 Early overall design.......................................................................................... 22
Figure 9 Overall design revision two.............................................................................. 25
Figure 10 TCP file transfer ............................................................................................. 27
Figure 11 TCP file transfer with Ethernut ...................................................................... 28
Figure 12 The player interaction with the whole network.............................................. 29
Figure 13 The ring buffer................................................................................................ 30
Figure 14 TCP file transfer through the Ethernut with a ring buffer.............................. 31
Figure 15 Writing data to the decoder command register .............................................. 33
Figure 16 Writing data to the decoder data register........................................................ 33
Figure 17 Interrupt service routine to transfer data to the decoder................................. 35
Figure 18 First program to play MP3 data...................................................................... 37
Figure 19 Program to play MP3 data that refills buffer if buffer empties...................... 39
Figure 20 The openMP3 function................................................................................... 43
Figure 21 Play/pause implementation............................................................................. 46
Figure 22 Buffer control delays...................................................................................... 48
Figure 23 Buttons with GAP message for buffer control ............................................... 50
Figure 24 Writing to the LCD command register........................................................... 53
Figure 25 The initialisation of the LCD [23].................................................................. 54
Figure 26 The print screen function................................................................................ 55
Figure 27 Song name extraction ..................................................................................... 56
Figure 28 A web page as the GUI................................................................................... 58
Figure 29 Winamp screen shot ....................................................................................... 60
List of tables
Table 1 The AudioTron versus SimpleFi ....................................................................... 10
Table 2 The ideal player specifications .......................................................................... 11
Table 3 The connections between the Ethernut and the VLSI piggy back board........... 32
Table 4 The LCD connections to the Ethernut ............................................................... 52
Table 5 Final player specifications ................................................................................. 61
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