Table of Contents
Advertisement
Solution Systems Technologies Inc.
Debugger General Information
The status codes that may be set by the bus master are:
ASCII
3
ASCII
The Multiprocessor Address Register (MPAR), located in shared RAM
location of $3004 offset from the base address the debugger loads it at, contains
the second of two words used to control communication between processors.
The MPAR contents specify the address at which execution for the remote
processor is to begin if the MPCR contains a G or B. The MPAR is organized as
follows:
$3004
At power up, the debug monitor self-test routines initialize RAM, including
the memory locations used for multi-processor support ($3000 through $3007).
The MPCR contains $00 at power-up, indicating that initialization is not yet
complete. As the initialization proceeds, the execution path comes to the
"prompt" routine. Before sending the prompt, this routine places an R in the
MPCR to indicate that initialization is complete. Then the prompt is sent.
If no terminal is connected to the port, the MPCR is still polled to see whether
an external processor requires control to be passed to the dual-port RAM. If a
terminal does respond, the MPCR is polled for the same purpose while the
serial port is being polled for user input.
An ASCII G placed in the MPCR by a remote processor indicates that the Go
Direct type of transfer is requested. An ASCII B in the MPCR indicates that
breakpoints are to be armed before control is transferred (as with the GO
command).
In either sequence, an E is placed in the MPCR to indicate that execution is
underway just before control is passed to RAM. (Any remote processor could
examine the MPCR contents.)
If the code being executed in dual-port RAM is to reenter the debug monitor,
a TRAP #496 call using function $0063 (SYSCALL .RETURN) returns control
to the monitor with a new display prompt. Note that every time the debug
monitor returns to the prompt, an R is moved into the MPCR to indicate that
control can be transferred once again to a specified RAM location.
3-16
Solution Systems Technologies Inc.
720-565-5995 | info@solusys.com | www.solusys.com
G (HEX 47)
Use Go Direct (GD) logic specifying the
MPAR address.
B (HEX 42)
Install breakpoints using the Go (G) logic.
*
*
720-565-5995 | info@solusys.com | www.solusys.com
*
*
(MPAR)
Installation Guide
Advertisement
Table of Contents
