HD404654 Datasheet, PDF (46/111 Pages) Hitachi Semiconductor – 4-Bit Single-Chip Microcomputer

HD404654 Series
Serial mode register 1A (SM1A: $005)
Bit
Initial value
Read/Write
Bit name
3
0
W
SM1A3
2
0
W
SM1A2
1
0
W
SM1A1
0
0
W
SM1A0
R4₁/SCK₁
SM1A3 mode selection
0
R4₁
1
SCK₁
SM1A2 SM1A1 SM1A0 SCK₁ Clock source
0
0
0 Output Prescaler
Prescaler
division
ratio
÷2048
1 Output Prescaler
÷512
1
0 Output Prescaler
÷128
1 Output Prescaler
÷32
1
0
0 Output Prescaler
÷8
1 Output Prescaler
÷2
1
0 Output System clock —
1 Input External clock —
Figure 28 Serial Mode Register 1A (SM1A)
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 29 Port Mode Register A (PMRA)
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