UPD78F0988AGC-8BS Renesas Electronics America, UPD78F0988AGC-8BS Datasheet - Page 288

• Manufacturer Part Number: UPD78F0988AGC-8BS
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0988AGC-8BS

• Lead Free Status / Rohs Status: Supplier Unconfirmed

286
Symbol
(3) Memory size switching register (IMS)
IMS
This register sets the capacities of the internal ROM and internal high-speed RAM.
IMS is set by an 8-bit memory manipulation instruction.
RESET input sets this register to CFH.
Note
Cautions 1. The value of IMS after reset is the same (CFH) for all the products in the PD780988
Notes 1. There is no need to change the set value of IMS because the initial value of the PD780988 is
RAM2 RAM1 RAM0
7
Make the flash memory capacity 48 KB or less when using the external device expansion function with
the PD78F0988A.
2. Set C4H, C6H, C8H, CCH, or CFH according to the mask ROM version used.
2. The external memory space can be expanded in a space other than that specified by IMS,
6
CFH.
Subseries, regardless of the internal memory capacity. Therefore, be sure to set the value
of IMS according to the internal memory capacity of the product used.
regardless of the internal memory capacity.
Table 15-3. Set Value of Internal Memory Size Switching Register
5
Figure 15-4. Format of Memory Size Switching Register
CHAPTER 15 EXTERNAL DEVICE EXPANSION FUNCTION
4
0
PD780982
PD780983
PD780984
PD780986
PD780988
PD78F0988A
ROM3 ROM2 ROM1 ROM0
3
Part Number
2
User’s Manual U13029EJ7V1UD
1
0
ROM3 ROM2
RAM2 RAM1
Other than above
Other than above
0
0
1
1
1
1
Set Value of IMS
Address
FFF0H
CFH
Note 2
1
1
0
1
1
1
CCH
C4H
C6H
C8H
Note 1
ROM1 ROM0
RAM0
After reset
0
1
0
0
1
0
CFH
Internal high-speed RAM capacity selection
1,024 bytes
Setting prohibited
0
0
0
0
1
Internal ROM capacity selection
16 KB
24 KB
32 KB
48 KB
60 KB
Setting prohibited
R/W
R/W
Note