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用于TM1300/PNX1300系列DSP（主要用于视频处理）的动态下载程序源码。

This demo contains a simple pSOS based command dispatcher
(see root.c), plus three sample demo commands (latency.c, 
task_demo.c and print_args.c). 

Root.c will be compiled and linked with pSOS into a code 
segment of type 'dynboot', and is able to load, run, and 
unload code segments of type 'app'. 'App's are programs 
which have a main(argc,argv) like entry point (see the 
implementation of task_demo and print_args), 
and are *not* self-contained: they must be loaded
by an already running tm1 program. They cannot be loaded
and run directly using tmsim or tmmon. Note that 'apps' lack all
of the system libraries (libraries for doing i/o using
printf, or the pSOS library). E.g. tmsize on print_args will reveal
that its text segment contains only 512 bytes, which is considerably
smaller than 'normal' executables of type boot or dynboot. System
libraries are contained by the command dispatcher, and 
will be connected to during dynamic loading after which
they can be normally used by the application.

See the last two rules of the Makefile to see how 'apps' should
be created: linked against the dynamic pSOS library to locate 
the pSOS functions which they might call, and with option '-btype app'
to indicate that they will be loaded by means of the dynamic loader.

The build structure has been derived from one of the
pSOS demo apps by setting the macro DYNAMIC in the Makefile
to the value 'dynamic', and adapting root.c to implement a
command dispatcher. The macro value 'dynamic' links in the dynamic loader,
allowing the command dispatcher to dynamically load the application
files.

The command dispatcher repeatedly accepts a command string, and
interprets the first word in this string as the name of an object
file containing an 'app'. A task is created for running the command,
and the command string is passed in argc/argv format to this task.
After start, the task will attempt to load the code from argv[0],
and when succeeded it will call its main function with argc/argv.
When this function terminates, the exit status is printed, and 
the corresponding code is unloaded. In case pSOS tasks are created
by the loaded command, it is the responsibility of the command itself
to make sure that all tasks have been deleted (and certainly are not
still executing) before main terminates. 

Any application, for instance any .app file in the other examples,
can be started using the command dispatcher; it will run 
in parallel with previously started and not yet terminated
applications, to be scheduled by pSOS. When running one or more
applications, the provided latency app can be used to sample the
interrupt latencies for a specified number of seconds (default duration
is 10 seconds):

> vivot.app
> patest.app
> latency.app 100 


See also the dynlnk_demo in the $(TCS)/OS/pSOS/pSOSystem.