System information

8.1 PCI Bus Analyzer
8.1.2 Controller Software
The PCI trace software is a Linux console program. The program initializes, starts and
stops the trace module via an address window on the AHB bus. After a successful trace,
the program reads out the FIFO containing the traced PCI signals and stores them to a
file. The data is formatted in a human readable way. Every line in the file represents one
PCI cycle. The following command calls the PCI trace program:
$ pci_trace -s -a <PCI address> -o <PCI command> -f <filename>
The option -s starts the trace module. The options -a and -o set up the trigger conditions.
With the aid of the option -f the traced PCI data can be written to a file. There is also
an interactive mode of the program in which it can be started without parameters. The
configuration of the trace module is made by typing commands to the console input stream.
$ pci_trace
> CHARM-PCI-Tracer v1.0
> READY
>
< setaddress 0xA0000
> OK, Trigger Address is set to 0xa0000
< start
> WAITING
> WAITING
For example, the console output above shows an interactive mode of the trace program.
The user sets up the trigger address to 0xA0000 and starts the trace module. The Yapt
program uses the trace program in the interactive mode. It will be discussed in the next
section.
8.1.3 GUI of the Analyzer
The software Yapt is a GUI wrapper for the PCI trace program [98]. The program allows a
comfortable usage of the CHARM PCI bus analyzer while hiding the command set of the
trace console program.
Figure 8.2 shows a screen shot of the GUI. It is a JAVA application running on an
arbitrary remote computer. It connects to the CHARM trace program and enables remote
control of the CHARM PCI bus analyzer. The trace program does not support remote
control capability of its own. Therefore, the Internet daemon (Inet) is used to provide a
network interface for the trace program. The Inet daemon is the service which controls who
can connect to your computer and which services they can use.
The Inet daemon is a super-server daemon on many Unix systems which manages various
Internet services [99]. This daemon links the input/output stream of a network socket to
the console input/output port of an arbitrary program. Figure 8.3 shows the data flow
between the Yapt software and the PCI trace program. First, Yapt has to be initialized
with the IP address of the CHARM PCI bus analyzer. Subsequently, Yapt connects to the
TCP port 45000 of the CHARM card. The Inet daemon of the CHARM card starts the PCI
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