Specifications

MP3 decoder
Buffer
Networking
The player
Microsoft
Windows
Graphical
User interface
Server program
Computer
Figure 9 Overall design revision two
The player makes the request to the server for the file system information. The server
retrieves the required information from Windows and sends it back to the player which
in turn sends the information to the GUI. The user then use the GUI to navigate the file
system and the nut sends this to the server. This continues until the play list is
composed. When the user wants to play a file the server opens the file and sends the
data to the MP3nut which then transmits it out of a buffer to the MP3 decoder.
5.3.2 Sending data from the PC to the Ethernut.
This was the first stage of testing with the Ethernut board and its operating system. To
become familiar with the Nut OS and the AVR-GCC compiler initially the test code
examples provided in the Nut OS were compiled and programmed onto the Atmel.
From these a TCP server was setup that could be Telnet into, and hence test that the
board was functioning as described. After determining that all parts of the Ethernut
board were working the first stage of code development began.
The first stage was just to setup a simple TCP server program on the Ethernut that
echoed what it received through TCP stream to the serial port to be displayed on
HyperTerminal. A client program was then set up on the PC to connect to the Ethernut
and then send text at regular intervals.
It was at this stage it was discovered that there were two ways to handle the TCP
packets on the Ethernut. The receiving and sending of TCP packets can be handled
directly through the functions NutTCPSend and NutTCPRecieve which are very similar
to the equivalent functions in Windows and UNIX. They are blocking functions, so that
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