HD6473887 Datasheet, PDF (37/523 Pages) Renesas Technology Corp – Hitachi 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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