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Programming Model
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3-51
3
rom b siz The rom b siz control bits are the size of ROM/Flash for Block
B. They are encoded as shown in the following table.
rom_b_rv and rom_a_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
rom_b_rv is initialized at power-up reset to match the inverse of the value
on the CKD1 pin.
rom b en When rom b en is set, accesses to Block B ROM/Flash in the
address range selected by ROM B BASE are enabled. When rom b en is
cleared they are disabled.
rom b we When rom b we is set, writes to Block B ROM/Flash are
enabled. When rom b we is cleared they are disabled. Refer back to
for more details.
Table 3-18. ROM/Flash Block B Size Encoding
rom b siz
BLOCK SIZE
%000
1Mbytes
%001
2Mbytes
%010
4Mbytes
%011
8Mbytes
%100
16Mbytes
%101
32Mbytes
%110
64Mbytes
%111
Reserved