Fujitsu FR60 Hardware Manual page 111

[Detailed explanation of the register]
MODR
7
000FFFF8
0
H
[Bits 7 to 3] Reserved bits
Be sure to set bits 7 to 3 to 00000. If any other value is set for these bits, operation is unpredictable.
[Bit 2] ROMA (Internal ROM enable bit)
This bit indicates whether to enable internal F-bus RAM and F-bus ROM areas.
ROMA Function
0 External ROM mode
1 Internal ROM mode
[Bits 1, 0] WTH1, WTH0 (Bus width specification bit)
These bits indicate the bus width specification to be used in external bus mode.
In external bus mode, this value is set in the BW1 and BW0 bits of AMD0 (CS0 area).
WTH1 WTH0
0 0
0 1
1 0
1 1
6 5 4 3
0 0 0 0
The internal F-bus RAM is enabled, and the internal ROM
area (80000
area.
The internal F-bus RAM and F-bus ROM are enabled.
Function
8-bit bus width
16-bit bus width
-
Single-chip mode
2 1 0
ROMA WTH1 WTH0 XXXXXXXX
Operation mode setting bits
Remarks
to 100000 ) becomes the external ROM
H H
Remarks
External bus mode
External bus mode
Setting prohibited
Single-chip mode
Initial value
B
93