Motorola MVME162LX User Manual

Calling System Utilities from User Programs

4-11

A convenient way of doing character input/output and many other 
useful operations has been provided so that you do not have to 
write these routines into the target code. You can access various 
162Bug routines via one of the MC68040 TRAP instructions, using 
vector #15. Refer to the Debugging Package for Motorola 68K CISC 
CPUs User's Manual for details on the various TRAP #15 utilities 
available and how to invoke them from within a user program. 

This section explains how to avoid contaminating the operating 
environment of the debugger. Topics covered include:

❏

162Bug Vector Table and workspace

❏

Hardware functions

❏

Exception vectors used by 162Bug

162Bug uses certain of the MVME162LX onboard resources and 
may also use offboard system memory to contain temporary 
variables, exception vectors, etc. If you disturb resources upon 
which 162Bug depends, then the debugger may function unreliably 
or not at all. 

If your application enables translation through the Memory 
Management Units (MMUs), and if your application utilizes 
resources of the debugger (e.g., system calls), your application must 
create the necessary translation tables for the debugger to have 
access to its various resources. The debugger honors the enabling of 
the MMUs; it does not disable translation.