CHAPTER 4 MEMORY BANK SELECT FUNCTION (
µ
PD78F0536, 78F0537, AND 78F0537D ONLY)
Preliminary User’s Manual U17260EJ3V1UD
90
4.2 Memory Bank Select Register (BANK)
The memory bank select register (BANK) is used to select a memory bank to be used.
BANK can be set by an 8-bit memory manipulation instruction.
Reset signal generation clears BANK to 00H.
Figure 4-2. Format of Memory Bank Select Register (BANK)
Address: FFF3H After reset: 00H R/W
Symbol
7 6 5 4 3 2 1 0
BANK
0 0 0 0 0
BANK2
BANK1
BANK0
Bank setting
BANK2
BANK1
BANK0
µ
PD78F0536
µ
PD78F0537, 78F0537D
0
0
0
Common area (32 K) + memory bank 0 (16 K)
0
0
1
Common area (32 K) + memory bank 1 (16 K)
0
1
0
Common area (32 K) + memory bank 2 (16 K)
0
1
1
Common area (32 K) + memory bank 3 (16 K)
1
0
0
Common area (32 K) +
memory bank 4 (16 K)
1
0
1
Setting prohibited
Common area (32 K) +
memory bank 5 (16 K)
Other than above
Setting prohibited
Caution Be sure to change the value of the BANK register in the common area (0000H to 7FFFH).
If the value of the BANK register is changed in the bank area (8000H to BFFFH), an inadvertent
program loop occurs in the CPU. Therefore, never change the value of the BANK register in the
bank area.
