Motorola MVME5500 Installation And Use Manual page 62

MOTLoad Firmware
3
3-20
The selection of the mailbox used by remote start on an individual
MVME5500 is determined by the setting of a global environment variable
(GEV). The default mailbox is zero. Another GEV controls whether
remote start is enabled (default) or disabled. Refer to the Remote Start
chapter in the MOTLoad Firmware Package User's Manual for remote
start GEV definitions.
The MVME5500's IBCA needs to be mapped appropriately through the
master's VMEbus bridge. For example, to use remote start using mailbox
0 on an MVME5500 installed in slot 5, the master would need a mapping
to support reads and writes of address 0x002ff348 in VME CR/CSR space
(0x280000 + 0x7f348).
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