µPD178023, 178024
2.2 Internal Extension RAM Size Select Register (IXS)
The internal extension RAM size select register (IXS) sets the internal extension RAM capacity.
Use the µPD178023, µPD178024 with the initial value (0CH).
Use an 8-bit memory manipulation instruction to set the IXS.
This register is set to 0CH at reset.
Caution Do not assign a value other than that the value at reset.
Figure 2-3. Format of Internal Extension RAM Size Select Register (IXS)
Symbol
IXS
7
0
6
0
5
0
4
3
2
1
0
Address
FFF4H
At reset
0CH
R/W
R/W
IXRAM4
I
XRAM3
I
XRAM2
I
XRAM1
I
XRAM0
IXRAM4 IXRAM3 IXRAM2 IXRAM1 IXRAM0
Selects Internal Extension RAM Capacity
0
1
1
0
0
0 byte
Others
Setting prohibited
Table 2-2 indicates the setting of IXS.
Table 2-2. Set Value of Internal Extension RAM Size Select Register
Targeted Model
Set Value of IXS
0CH
µPD178023, 178024
18
Data Sheet U14126EJ1V0DS00
NEC [ NEC ]
