PD78F0066_15 Datasheet, PDF (17/30 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCONTROLLER

µPD78F0066
4. INTERNAL EXPANSION RAM SIZE SWITCHING REGISTER (IXS)
The internal expansion RAM size switching register (IXS) is the register that sets the internal expansion RAM
capacity.
IXS is set with a 1-bit memory manipulation instruction or an 8-bit memory manipulation instruction.
RESET input sets IXS to 0CH.
Caution To initialize the program, be sure to set IXS to 04H. Also be sure to set IXS to 04H after
resetting, because reset input sets IXS to 0CH.
Figure 4-1. Format of Internal Expansion RAM Size Switching Register
Symbol 7
6
5
4
3
2
1
0 Address After reset R/W
IXS 0
0
0
0 IXRAM3 IXRAM2 IXRAM1 IXRAM0 FFF4H
0CH
R/W
IXRAM3 IXRAM2 IXRAM1 IXRAM0 Selection of Internal Expansion RAM Capacity
0
1
0
0 4096 bytes
Others
Setting prohibited
Preliminary Product Information
15