Data Formats; General Register Data Formats; Figure 2.9 General Register Data Formats (1) - Renesas H8S/2437 Hardware Manual

2.5

Data Formats

The H8S/2600 CPU can process 1-bit, 4-bit BCD, 8-bit (byte), 16-bit (word), and 32-bit
(longword) data. Bit-manipulation instructions operate on 1-bit data by accessing bit n (n = 0, 1, 2,
..., 7) of byte operand data. The DAA and DAS decimal-adjust instructions treat byte data as two
digits of 4-bit BCD data.
2.5.1

General Register Data Formats

Figure 2.9 shows the data formats in general registers.
Data Type
1-bit data
1-bit data
4-bit BCD data
4-bit BCD data
Byte data
Byte data
Rev. 1.00, 09/03, page 28 of 704
Register Number
RnH
RnL
RnH
RnL
RnH
RnL

Figure 2.9 General Register Data Formats (1)

Data Format
7 0
7 6 5 4 3 2 1 0
7
Don't care
7
7 4 3 0
Upper Lower
7
Don't care
7 0
MSB LSB
7
Don't care
MSB
Don't care
0
6 5 4 3 2 1 0
Don't care
4 3 0
Upper Lower
Don't care
0
LSB