HD6413008VF25 Datasheet, PDF (70/688 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

2. CPU
2.5 Data Formats
The H8/300H 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
Figures 2.6 and 2.7 show the data formats in general registers.
Data Type
1-bit data
General
Register
RnH
Data Format
7
0
76543210
Don't care
1-bit data
RnL
Don't care
7
0
76543210
4-bit BCD data
RnH
7 43 0
Upper digit Lower digit
Don't care
4-bit BCD data
RnL
Don't care
7
43
0
Upper digit Lower digit
Byte data
Byte data
RnH
RnL
7
0
Don't care
MSB
LSB
7
0
Don't care
MSB
LSB
Legend:
RnH: General register RH
RnL: General register RL
MSB: Most significant bit
LSB: Least significant bit
Figure 2.6 General Register Data Formats (1)
Rev.4.00 Aug. 20, 2007 Page 24 of 638
REJ09B0395-0400