E202075_HD404889 Datasheet, PDF (126/202 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

HD404889/HD404899/HD404878/HD404868 Series
Port mode register 3 (PMR3: $00B):
Port mode register 3 (PMR3) has the following functions. See figure 71.
• R2₁/SCK pin selection
• R2₂/SI/SO pin selection
Port mode register 3 (PMR3) is a 4-bit write-only register used to select serial interface pin settings as
shown in figure 71. It is reset to $0 by an MCU reset.
Port mode register 3 (PMR3: $00B)
Bit
3
2
1
0
Read/Write
W
W
W
W
Initial value on reset 0
0
0
0
Bit name
PMR33 PMR32 PMR31 PMR30
PMR30 R20/TOC pin mode selection
0
R20
1 TOC
PMR31 R21/SCK pin mode selection
0
R21
1 SCK
PMR33 PMR32 R22/SI/SO pin mode selection
0
*
R22
0 SI
1
1 SO
* : Don't care
Figure 71 Port Mode Register 3 (PMR3)
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