HD404369 Datasheet, PDF (85/117 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer

HD404369 Series
Port Mode Register A (PMRA: $004): This register has the following functions (figure 67).
• R0₁/SI pin function selection
• R0₂/SO pin function selection
Port mode register A (PMRA: $004) is a 4-bit write-only register, and is reset to $0 by MCU reset.
Port mode register A (PMRA: $004)
Bit
Initial value
Read/Write
Bit name
3
2
1
0
0
0
0
0
W
W
W
W
PMRA3 PMRA2 PMRA1 PMRA0
PMRA2
0
1
R0₃/TOC Mode Selection
R0₃
TOC
PMRA3
0
1
D₃/BUZZ Mode Selection
D₃
BUZZ
PMRA0
0
1
R0₂/SO Mode Selection
R0₂
SO
PMRA1
0
1
R0₁/SI Mode Selection
R0₁
SI
Figure 67 Port Mode Register A (PMRA)
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