HD64F3687HV Datasheet, PDF (53/538 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

Section 2 CPU
2.3 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.
2.3.1 General Register Data Formats
Figure 2.5 shows the data formats in general registers.
Data Type
1-bit data
1-bit data
General Register
RnH
RnL
4-bit BCD data
RnH
Data Format
7
0
7 6 5 4 3 2 10
Don't care
Don't care
7
0
7 6 5 4 3 2 10
7
43
0
Upper
Lower
Don't care
4-bit BCD data
RnL
Don't care
7
43
0
Upper
Lower
Byte data
Byte data
RnH
RnL
7
MSB
Don't care
0
LSB
7
Don't care
0
MSB
LSB
Figure 2.5 General Register Data Formats (1)
Rev.5.00 Nov. 02, 2005 Page 19 of 500
REJ09B0027-0500