Rom Mirror Function Select Register (Romm) - Fujitsu MB90420/5 (A) Series Hardware Manual

MB90420/5 (A) SERIES F

22.2 ROM Mirror Function Select Register (ROMM)

Do not access the ROM mirror function select register (ROMM) when addresses 004000
being accessed.
n ROM mirror function select register (ROMM)
Address: 00006F
H
Read/write →
Initial value →
[bit 8] MI
The ROM data in the FF bank can also be read in the 00 bank when '1' is set to this bit. However, this
will not be performed when this bit is set to '0'. This bit is write only.
Note: Only FF4000 to FFFFFF is mirrorred to 004000 to 00FFFF when ROM mirror function is activated.
Therefore, addresses FFF000 to FF3FFF will not be mirrorred to 00 bank.
FFFFFF
Address1
010000
004000
Address2
000100
0000C0
000000
2
MC-16LX FAMILY 16-BIT MICROCONTROLLERS HARDWARE MANUAL
15 14
— —
— —
— —
H
H
H
H
H
H
When MI = 1
Fig. 22.2 Memory Space
13 12 11
— — —
— — —
— — —
When MI = 0
22-4
to 00FFFF
H
10 9 8
— — MI
— — (W)
— — (1)
Internal
are
H
← Bit No.
ROMM
memory