E202075_HD404889 Datasheet, PDF (146/202 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

HD404889/HD404899/HD404878/HD404868 Series
Port mode register 4 (PMR4: $00C):
Port mode register 4 (PMR4) is a 4-bit write-only register that enables the R3 to R6 port pins to be
switched to SEG1 to SEG16 pin functions in 4-port units (figure 90).
Port mode register 4 (PMR4: $00C)
Bit
Read/Write
Initial value on reset
Bit name
3
2
1
0
W
W
W
W
0
0
0
0
PMR43 PMR42 PMR41 PMR40
PMR40 R3/SEG1 to SEG4 pin mode selection
0 R3
1^* SEG1–4
PMR41 ^{R4/SEG5 to SEG8 pin mode selection}
0 R4
1^* SEG5–8
PMR42 ^{R5/SEG9 to SEG12 pin mode selection}
0 R5
1^* SEG9–12
PMR43 ^{R6/SEG13 to SEG16 pin mode selection}
0 R6
1^* SEG13–16
Note: ^* When use as a segment output pin, write its port data resister (PDR) to "0"
Figure 90 Port Mode Register 4 (PMR4: $00C)
144