UPD78F0078GK-9ET-A Renesas Electronics America, UPD78F0078GK-9ET-A Datasheet - Page 421

• Manufacturer Part Number: UPD78F0078GK-9ET-A
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0078GK-9ET-A

• Lead Free Status / Rohs Status: Supplier Unconfirmed

20.2 External Device Expansion Function Control Registers
(1) Memory expansion mode register (MEM)
Address: FF47H After reset: 00H R/W
Symbol
MEM
The external device expansion function is controlled by the following two registers.
• Memory expansion mode register (MEM)
• Memory expansion wait setting register (MM)
MEM sets the external expansion area.
MEM is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input clears MEM to 00H.
Caution
(Note is shown in the next page.)
Other than above
MM2
7
0
0
0
0
1
1
1
Figure 20-2. Format of Memory Expansion Mode Register (MEM)
When using the falling edge detection function of port 4, be sure to set MEM to 01H.
MM1
6
0
0
0
1
0
0
1
CHAPTER 20 EXTERNAL DEVICE EXPANSION FUNCTION
MM0
5
0
0
1
1
0
1
1
Single-Chip/Memory
Expansion Mode Selection P40 to P47 P50 to P53 P54, P55 P56, P57 P64 to P67
Single-chip mode
Port 4 falling edge
detection mode
Memory
expansion mode
mode
Setting prohibited
User’s Manual U14260EJ4V0UD
4
0
Note
256-byte
4 KB
mode
16 KB
mode
Full-address
mode
3
0
Port mode
AD0 to AD7 Port mode
MM2
2
P40 to P47, P50 to P57, P64 to P67 Pin State
A8 to A11 Port mode
MM1
1
A12, A13 Port mode
MM0
0
A14, A15
P64 = RD
P65 = WR
P66 =WAIT
P67 = ASTB
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