HD404369 Datasheet, PDF (51/117 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer

HD404369 Series
Data control register (DCD0 to 3: $02C to $02F)
(DCR0 to 9: $030 to $039)
DCD0 to DCD3, DCR0 to DCR9
Bit
3
2
1
0
Initial value
0
0
0
0
Read/Write
W
W
W
W
Bit name
DCD03– DCD02– DCD01– DCD00–
DCD23, DCD22, DCD31, DCD30,
DCR03– DCR02– DCR01– DCR00–
DCR63, DCR92 DCR91 DCR90
DCR83–
DCR93
Bits 0 to 3
0
1
CMOS Buffer On/Off Selection
Off (high-impedance)
On
Correspondence between ports and DCD/DCR bits
Register Name
Bit 3
Bit 2
DCD0
DCD1
DCD2
DCD3
D₃
D₇
D₁₁
Not used
D₂
D₆
D₁₀
Not used
DCR0
DCR1
DCR2
DCR3
DCR4
DCR5
DCR6
DCR7
DCR8
DCR9
R0₃
R0₂
R1₃
R1₂
R2₃
R2₂
R3₃
R3₂
R4₃
R4₂
R5₃
R5₂
R6₃
R6₂
Not used
R7₂
R8₃
R8₂
R9₃
R9₂
Bit 1
D₁
D₅
D₉
D₁₃
R0₁
R1₁
R2₁
R3₁
R4₁
R5₁
R6₁
R7₁
R8₁
R9₁
Figure 28 Data Control Registers (DCD, DCR)
Bit 0
D₀
D₄
D₈
D₁₂
R0₀
R1₀
R2₀
R3₀
R4₀
R5₀
R6₀
R7₀
R8₀
R9₀
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