PD178046_15 Datasheet, PDF (19/42 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCONTROLLER

µPD178046, 178048
2.2 Internal Expansion RAM Size Select Register (IXS)
The internal expansion RAM capacity can be selected by using the internal expansion RAM size select register.
This register of the µPD178046 and 178048 must be set to 0BH.
Use an 8-bit memory manipulation instruction to set IXS.
The value of this register is set to 0CH at reset.
Figure 2-3. Format of Internal Expansion RAM Size Select Register (IXS)
Symbol 7
6
5
4
3
2
1
0
Address At reset R/W
IXS 0
0
0 IXRAM4 IXRAM3 IXRAM2 IXRAM1 IXRAM0
FFF4H
0CH
R/W
IXRAM4 IXRAM3 IXRAM2 IXRAM1 IXRAM0
Selects internal expansion RAM capacity
0
1
0
1
1 512 bytes
Others
Setting prohibited
Preliminary Product Information
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