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MURPHY Create worst case overlay situation
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Purpose : Create a worst case overlay situation
Syntax : MURPHY
Default : Disabled
The MURPHY command causes the overlay manager to attempt to force any
inadvertent overlay errors (programming errors) to manifest themselves
during testing or debugging.
When MURPHY is enabled, the overlay manager will only allow a single overlay
to be in memory at any given time, allowing the developer to detect 'badly
behaved' dependencies between overlays and correct them.
The overlay manager also fills all unused space in the overlay pool with INT
3 instructions, with a far jump to an error reporting routine within the
overlay manager being placed at the very end of the overlay area.
When the program is run under a debugger, and an erroneous jump to an
invalid (i.e. non-vectored) address within the overlay area occurs, the INT
3 instruction will cause the debugger to breakpoint at the offending
address.
If the program is not being executed under a debugger, the processor will
execute all the INT 3 instructions and the far jump to the error routine in
the overlay manager, at which point the overlay manager will display a
message and terminate the program.
The use of the MURPHY command may slow down the execution of the program
significantly.
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