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CHAPTER 5 PORT FUNCTIONS
User’s Manual U12697EJ3V0UM
(3) Port function control register 2 (PF2)
This register specifies N-ch open drain for pins P25 and P27.
PF2 is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets PF2 to 00H.
Caution Only the
µ
PD784225Y Subseries incorporates PF2. When using the I
2
C bus mode (serial
interface), make sure to specify N-ch open drain for the P25 and P27 pins.
Figure 5-22. Format of Port Function Control Register 2 (PF2)
Address: 0FF42H After reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
PF2
PF27
0
PF25
0
0
0
0
0
PF2n
P2n pin N-ch open drain specification (n = 5, 7)
0
Don’t set N-ch open drain
1
Set N-ch open drain