HD404054 Datasheet, PDF (74/101 Pages) Hitachi Semiconductor – HMCS400-series microcomputers designed to increase program productivity with large-capacity memory

HD404054 Series/HD404094 Series
Transmit clock
Serial output
data
1
2
3
4
5
6
7
8
LSB
MSB
Serial input data
latch timing
Figure 57 Serial Interface Output Timing
Port Mode Register A (PMRA: $004): This register has the following functions (figure 58).
• R4₂/SI₁ pin function selection
• R4₃/SO₁ pin function selection
Port mode register A (PMRA: $004) is a 2-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
—
—
W
W
Not used Not used PMRA1 PMRA0
PMRA0
0
1
R4₃/SO₁ mode selection
R4₃
SO₁
PMRA1
0
1
R4₂/SI₁ mode selection
R4₂
SI₁
Figure 58 Port Mode Register A (PMRA)
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