upd78p058f Renesas Electronics Corporation., upd78p058f Datasheet - Page 21

• Manufacturer Part Number: upd78p058f
• Description: Mos Intergrated Circuit, 8-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

3. MEMORY SIZE SWITCHING REGISTER (IMS)
register (IMS), it is possible to get the same memory mapping as that of a mask ROM version having different internal
memories (ROM).
Symbol
IMS
Note Set the internal ROM capacity to 56 Kbytes or less when external device expansion function is used.
versions.
This is a register to disable use of part of internal memories by software. By setting this memory size switching
The IMS register is set with an 8-bit memory manipulation instruction.
RESET input sets IMS to CFH.
Table 3-1 shows the setting values of IMS which make the memory mapping the same as that of the mask ROM
RAM2
7
RAM1
6
Table 3-1. Memory Size Switching Register Setting Values
RAM0
5
Figure 3-1. Memory Size Switching Register Format
Target Mask ROM Version
4
0
ROM3
PD78056F
PD78058F
3
ROM2
2
ROM1
1
ROM3 ROM2 ROM1 ROM0
RAM2 RAM1 RAM0
IMS Setting Value
Others
Others
ROM0
1
1
1
1
0
CCH
CFH
1
1
1
1
Address
FFF0H
0
1
1
0
1024 bytes
Setting prohibited
High-Speed RAM Capacity
After Reset
0
0
1
Selection of Internal
CFH
Selection of Internal
48 Kbytes
56 Kbytes
60 Kbytes
Setting prohibited
ROM Capacity
PD78P058F
Note
R/W
R/W
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