Motorola MVME187 User Manual
Booting and Restarting 187Bug
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Memory Requirements
The program portion of 187Bug is approximately 512KB of code,
consisting of download, debugger, and diagnostic packages and
contained entirely in EPROM. The EPROM sockets on the
MVME187 are mapped starting at location $FF800000.
consisting of download, debugger, and diagnostic packages and
contained entirely in EPROM. The EPROM sockets on the
MVME187 are mapped starting at location $FF800000.
187Bug requires a minimum of 64KB of contiguous read/write
memory to operate.
memory to operate.
The ENV command controls where this block of memory is located.
Regardless of where the onboard RAM is located, the first 64KB is
used for 187Bug stack and static variable space and the rest is
reserved as user space.
Regardless of where the onboard RAM is located, the first 64KB is
used for 187Bug stack and static variable space and the rest is
reserved as user space.
Whenever the MVME187 is reset, the target IP is initialized to the
address corresponding to the beginning of the user space, and the
target stack pointers are initialized to addresses within the user
space, with the target Pseudo Stack Pointer (R31) set to the top of
the user space.
address corresponding to the beginning of the user space, and the
target stack pointers are initialized to addresses within the user
space, with the target Pseudo Stack Pointer (R31) set to the top of
the user space.
At power up or reset, all 8KB of memory at addresses $FFE0C000
through $FFE0DFFF is completely changed by the 187Bug initial
stack.
through $FFE0DFFF is completely changed by the 187Bug initial
stack.
Booting and Restarting 187Bug
This section covers the following tasks:
❏
Starting up 187Bug
❏
Autoboot
❏
ROMboot
❏
Network boot
❏
Restarting the system