UPD784938 Datasheet, PDF (163/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 6 PORT FUNCTIONS
6.7.2 I/O mode/control mode setting
The port 5 input/output mode is set for each pin by setting the port 5 mode register (PM5) as shown in Figure 6-45.
When port 5 pins can be used as port or address pins in 2-bit units, the setting is performed by means of the memory expansion
mode register (MM: See Figure 24-1) as shown in Table 6-7.
Figure 6-45. Port 5 Mode Register (PM5) Format
7
6
5
4
3
2
1
0 Address After reset R/W
PM5 PM57 PM56 PM55 PM54 PM53 PM52 PM51 PM50 0FF25H
FFH
R/W
PM5n ^{P5n Pin Input/Output Mode Specification}
(n = 0 to 7)
0 Output mode (output buffer on)
1 Input mode (output buffer off)
Table 6-7. Port 5 Operation Modes
MM Bits
Operation Mode
MM3
MM2
MM1
MM0
P50
P51
P52
P53
P54
P55
P56
P57
0
0
0
0
Port (P50 to P57)
0
0
1
1
0
1
0
0
A8
A9
Port
0
1
0
1
A8
A9
A10
A11
Port
0
1
1
0
A8
A9
A10
A11
A12
A13
Port
0
1
1
1
A8
A9
A10
A11
A12
A13
A14
A15
1
0
0
0
1
0
0
1
Preliminary User’s Manual U13987EJ1V0UM00
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