HD6433802H Datasheet, PDF (34/435 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

2.3.1 Data Formats in General Registers
Data of all the sizes above can be stored in general registers as shown in figure 2.3.
Data Type Register No.
Data Format
1-bit data
7
0
RnH 7 6 5 4 3 2 1 0
don’t care
1-bit data
RnL
don’t care
7
0
76543210
Byte data
7
RnH MSB
0
LSB
don’t care
7
0
Byte data
RnL
don’t care
MSB
LSB
15
0
Word data
Rn MSB
LSB
4-bit BCD data
RnH
7
4
Upper digit
3
0
Lower digit
don’t care
4-bit BCD data RnL
don’t care
7
4
Upper digit
3
0
Lower digit
Notation:
RnH: Upper byte of general register
RnL: Lower byte of general register
MSB: Most significant bit
LSB: Least significant bit
Figure 2.3 Register Data Formats
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