Motorola MVME2300 Series - Manual (Page 208)

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Falcon ECC Memory Controller Chip Set
3
bits wide, where each Falcon interfaces to 32 bits.
rom_a_64 matches the value that was on the CKD2 pin at
power-up reset. It cannot be changed by software.
rom a siz The rom a siz control bits are the size of ROM/Flash for
Block A. They are encoded as shown in
Table 3-14 .
rom_a_rv rom_a_rv and rom_b_rv determine which (if either) of
Blocks A and B is the source of reset vectors or any other
access in the range $FFF00000 - $FFFFFFFF as shown in
the table below.
rom_a_rv is initialized at power-up reset to match the
value on the CKD0 pin.
Table 3-14. ROM Block A Size Encoding
rom a siz Block Size
%000 1MB
%001 2MB
%010 4MB
%011 8MB
%100 16MB
%101 32MB
%110 64MB
%111 Reserved
Table 3-15. rom_a_rv and rom_b_rv Encoding
rom_a_rv rom_b_rv Result
0 0 Neither block is the source of reset
vectors.
0 1 Block B is the source of reset vectors.
1 0 Block A is the source of reset vectors.
1 1 Block B is the source of reset vectors.