HD404369 Datasheet, PDF (88/117 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer

HD404369 Series
Registers for A/D Converter Operation
A/D Mode Register 1 (AMR1: $019): Four-bit write-only register which selects digital or analog ports, as
shown in figure 70.
A/D mode register 1 (AMR1: $019)
Bit
Initial value
Read/Write
Bit name
3
0
W
AMR13
2
0
W
AMR12
1
0
W
AMR11
0
0
W
AMR10
AMR12
0
1
AMR13
0
1
R3₂/AN₂ Mode Selection
R3₂
AN₂
R3₃/AN₃ Mode Selection
R3₃
AN₃
AMR10
0
1
AMR11
0
1
R3₀/AN₀ Mode Selection
R3₀
AN₀
R3₁/AN₁ Mode Selection
R3₁
AN₁
Figure 70 A/D Mode Register 1 (AMR1)
A/D Mode register 2 (AMR2: $01A): Three-bit write-only register which is used to set the A/D
conversion period and to select digital or analog ports. Bit 0 of the A/D mode register selects the A/D
conversion period, and bits 1 and 2 select ports R4–R5 as pins AN₄–AN₁₁ in 4-pin units (figure 71).
A/D mode register 2 (AMR2: $01A)
Bit
Initial value
Read/Write
Bit name
3
2
1
0
—
0
0
0
—
W
W
W
Not used AMR22 AMR21 AMR20
AMR22
0
1
R5/AN₈–AN₁₁ Pin Selection
R5
AN₈–AN₁₁
AMR20
0
1
AMR21
0
1
Conversion Time
34 t_cyc
67 t_cyc
R4/AN₄–AN₇ Pin Selection
R4
AN₄–AN₇
Figure 71 A/D Mode Register 2 (AMR2)
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