Motorola MTX series - Table 3-16. Rom_A_Rv and Rom_B_Rv Encoding

3-48 Computer Group Literature Center Web Site
Falcon ECC Memory Controller Chip Set
3
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.
rom a en When rom a en is set, accesses to Block A ROM/Flash in the
address range selected by ROM A BASE are enabled. When rom a en is
cleared, they are disabled.
rom a we When rom a we is set, writes to Block A ROM/Flash are
enabled. When rom a we is cleared, they are disabled. Note that if
rom_a_64 is cleared, only 1-byte writes are allowed. If rom_a_64 is set,
only 4-byte writes are allowed. The Falcon ignores other writes. If a valid
Table 3-16. 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.