upd70f3017ay Renesas Electronics Corporation., upd70f3017ay Datasheet - Page 77

• Manufacturer Part Number: upd70f3017ay
• Description: V850/sa1tm 32-/16-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

3.4.6 External expansion mode
5, 6, and 9. To connect an external device, the port pins must be set to the external expansion mode by using the
memory expansion mode register (MM).
output is also possible by setting the memory address output mode register (MAM) (see IE-703017-MC-EMI User’s
Manual for debugging when using the separate bus).
function pins enter the port mode, and the external memory cannot be used. When the external memory is used
(external expansion mode), specify the MM register or MAM register by the program (memory area is set by the MM
register).
(1) Memory expansion mode register (MM)
After reset: 00H
Symbol
MM
The V850/SA1 allows external devices to be connected to the external memory space by using the pins of ports 4,
The address bus (A1 to A15) is set to multiplexed bus output with the data bus (D1 to D15), though separate bus
Because the V850/SA1 is fixed to single-chip mode in the normal operation mode, the port/control mode alternate-
Caution When switching to the external expansion mode, the P93 and P94 bits of port 9 (P9) must be set
Remark
This register sets the mode of each pin of ports 4, 5, 6, and 9. In the external expansion mode, an external
device can be connected to an external memory area of up to 4 MB. However, an external device cannot be
connected to the internal RAM area, on-chip peripheral I/O area, and internal ROM area in the single-chip mode
(and even if the external device is connected physically, it cannot be accessed).
The MM register can be read/written in 8-bit or 1-bit units. However, bits 4 to 7 are fixed to 0.
Other than above
MM2
MM3
0
0
1
1
1
to 1 before switching.
For details of the operation of each port pin, refer to 2.3 Description of Pin Functions.
0
1
7
0
MM1
R/W
0
1
0
0
1
Port mode
External expansion mode (HLDAK: P95, HLDRQ: P96)
6
0
MM0
0
1
0
1
×
P95 and P96 Operation Modes
5
0
expansion mode
expansion mode
expansion mode
expansion mode
Address Space
256 KB
64 KB
1 MB
4 MB
CHAPTER 3 CPU FUNCTIONS
—
User’s Manual U12768EJ4V1UD
Address: FFFFF04CH
4
0
RFU (reserved)
MM3
AD0 to
3
Port 4
AD7
MM2
2
AD8 to
Port 5
AD15
MM1
Port mode
1
A16,
A17
Port 6
MM0
A18,
A19
0
A20,
A21
R/W, DSTB,
WRH, RD
UBEN,
LBEN,
ASTB,
Port 9
WRL,
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