Motorola 700/800-Series User Manual

Preserving the Debugger Operating Environment

4-13

The only hardware resources used by the debugger are the EIA-
232-D ports, which are initialized to interface to the debug terminal 
and a host. If these ports are reprogrammed, the terminal 
characteristics must be modified to suit, or the ports should be 
restored to the debugger-set characteristics prior to reinvoking the 
debugger. 

The exception vectors used by the debugger are listed below. These 
vectors must reside at the specified offsets in the target program's 
vector table for the associated debugger facilities (breakpoints, 
trace mode, etc.) to operate. 

, the target stack pointer is left pointing past the bottom of the 

exception stack frame created; that is, it reflects the system stack 

$10

Illegal instruction

Breakpoints (used by GO, GN, GT)

$24

Trace

Trace operations (such as T, TC, TT)

$80-$B8

TRAP #0 - #14

Used internally

$BC

TRAP #15

System calls

$ Note 1

Level 7 interrupt

ABORT pushbutton

$ Note 2

Level 7 interrupt

AC Fail

$DC

FP Unimplemented Data Type

Software emulation and data type 
conversion of ßoating point data. 

Notes
1.

This depends on what the Vector Base Register (VBR) is set to in the MC2chip. 

2.

This depends on what the Vector Base Register (VBR) is set to in the VMEchip2.