Technical data

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177Bug Firmware
3
Note
Memory Configuration Defaults.
The default configuration for Dynamic RAM mezzanine boards will position the mezzanine with
the largest memory size to start at the address selected with the ENV parameter "Base Address of
Dynamic Memory". The Base Address parameter defaults to 0. The smaller sized mezzanine will
follow immediately above the larger in the memory map. If mezzanines of the same size and type
are present, the first (closest to the board) is mapped to the selected base address. If mezzanines of
the same size but different type (parity and ECC) are present, the parity type will be mapped to the
selected base address and the ECC type mezzanine will follow. The SRAM does not default to a
location in the memory map that is contiguous with Dynamic RAM.
Base Address of Local Memory 00000000 Beginning address of Local Memory (ECC
type memory on the MVME177P). Must be a
multiple of the Local Memory board size,
starting with 0. Default is $0.
Size of Local Memory Board 0 00000000 You are prompted twice, once for each
possible MVME177P memory board. The
default is the calculated size of the memory
board.
Size of Local Memory Board 1 00000000
ENV asks the following series of questions to set up the VMEbus interface for the MVME177P
modules. You should have a working knowledge of the VMEchip2 as given in the MVME1X7P
Single Board Computers Programmer’s Reference Guide in order to perform this configuration.
The slave address decoders are used to allow another VMEbus master to access a local resource of
the MVME177P. There are two slave address decoders set. They are set up as follows:
Slave Enable #1 [Y/N] Y Yes, set up and enable Slave Address Decoder
#1.
Slave Starting Address #1 00000000 Base address of the local resource that is
accessible by the VMEbus. Default is the base
of local memory, $0.
Slave Ending Address #1 000FFFFF Ending address of the local resource that is
accessible by the VMEbus. Default is the end
of calculated memory.
Table 3-3. ENV Command Parameters (Continued)
ENV Parameter and Options Default Meaning of Default