Use of VxWorks Exception Task - "tExcTask"

[Jim Lally]

Using Tornado 2.0 - VxWorks 5.4 - Motorolla 68K platforms

I'm trying to identify all uses of the vxWorks exceptions task
"tExcTask". Any Help would be appreciated.

Currently identified uses are:

· Exception Handling Processing that must be done in a task context!
Possibly when "excHookAdd" used?

· Watchdog Timer support!

· Debugging support! Setting up of breakpoints, etc.?

· Use of Unix like signaling mechanism! Delivery of signals to
multiple tasks? Signaling handler executing in tExcTask task context?

· Library dependencies are: dbgLib (Debugger), sigLib (Signal
Library), and intLib (hardware specific interrupt library).

· Supports a task's deletion by executing taskDelete Hooks for tasks
deleting themselves.

Any help would be appreciated.

[Vijay Kumar Peshkar]

Also tExcTask can be used by Interrupt Service Routines to facilitate execution of
code at task level. (Code executed at ISRs is executed at the Interrupt level)
_func_excJobAdd should be called at interrupt level with the correct parameters so that a request is sent to tExcTask. This communication from the
ISR to the tExctask is done using message Queues.
Since ISRs cannot WAIT for the message queues to be available, they just throw it into the queue (NO_WAIT) and hope it reaches the tExctask. In a
system receiving large number of interrupts, there is a possibility that this might get lost.

cheers,
Vijay