Using the 197Bug Debugger
4-6
Installation Guide
4
Other ways are by reading in the program from disk, using one of the disk
commands (
BO
,
BH
,
IOP
), or by reading the program as a file from a remote
computer on a network, using one of the network commands, such as
NIOP
.
Once the object code has been loaded into memory, the user can set
breakpoints if desired and run the code or trace through it.
Calling System Utilities From User Programs
A convenient way of doing character input/output and many other useful
operations has been provided so that the user does not have to write these
routines into the target code. The user has access to various 197Bug routines
via one of the MC88110 TRAP instructions, using vector #496. Refer to the
MVME197BUG 197Bug Debugging Package User’s Manual for details on the
various TRAP #496 utilities available and how to invoke them from within a
user program.
Preserving The Debugger Operating Environment
This section explains how to avoid contaminating the operating environment
of the debugger. 197Bug uses certain of the MVME197LE onboard resources
and also off-board system memory to contain temporary variables, exception
vectors, etc. If the user disturbs resources upon which 197Bug depends, then
the debugger may function unreliably or not at all.
197Bug Vector Table and Workspace
The debugger and diagnostic firmware resides in the FLASH memory. The
first 64KB of RAM is also used by the debugger for storage of the Vector Table,
executable code, variables, and stack.
Hardware Functions
The only hardware resources used by the debugger are the EIA-232-D ports,
which are initialized to interface to the debug terminal. 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.
Exception Vectors Used by 197Bug
The top 16 MC88110 exception vectors (i.e., #496 to 511 inclusive) are reserved
for use by the debugger.
Solution Systems Technologies Inc.
720-565-5995 | [email protected] | www.solusys.com
Solution Systems Technologies Inc.
720-565-5995 | [email protected] | www.solusys.com