HP 64746 User Manual page 113

Chapter 4: Configuring the Emulator
Selecting the Emulation Monitor Program
The monitor program makes possible emulation commands which access target
system resources. (The only way to access target system resources is through the
emulation processor.) For example, when you enter a command to modify target
system memory, it is the execution of monitor program instructions that cause the
new values to be written to target system memory.
When the emulation system controller recognizes that an emulation command
needs to access target system resources, it writes a command code to a
communications area and transitions the emulation processor execution into the
monitor program. The monitor program reads this command (and any associated
parameters) from the communications area and executes the appropriate
instructions to access these target system resources.
The Background Monitor
On emulator power-up, or after initialization, the emulator uses the background
monitor program. The background monitor program executes entirely in the
background emulator mode. The background monitor does not occupy processor
address space.
The Foreground Monitor
You can configure the emulator to use a foreground monitor program. When a
foreground monitor is selected, it executes in the foreground emulator mode. The
foreground monitor occupies processor memory space and executes as if it were
part of the user program.
When you use a foreground monitor, breaks into the monitor still cause the
emulator to execute a number of cycles in background. The difference between the
foreground monitor and the background monitor is that when the background
monitor is used, all monitor functions are executed in background; when the
foreground monitor is used, the monitor functions are executed in foreground.
The foreground monitors are supplied with the interface software and can be found
in the following path:
$HP64000/monitor/*
The monitor program named fmon68302.S should be assembled and linked with
the HP 64845 68000/10 Cross Assembler/Linker, and the monitor named
Mfmon68302.s should be assembled and linked with the HP 64870 assembler.
You may customize the foreground monitor if necessary; however, you must
maintain the basic communications protocol between the monitor and the emulation
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