Datasheet

Section 2 CPU
Rev.4.00 Nov. 02, 2005 Page 13 of 304
REJ09B0143-0400
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.
7 0
7
0
MSB LSB
MSB LSB
704 3
Don't care
Don't care
Don't care
7 04 3
70
Don't care
6543271
0
7
0
Don't care
65432710
Don't care
RnH
RnL
RnH
RnL
RnH
RnL
Data Type General Register Data Format
Byte data
Byte data
4-bit BCD data
4-bit BCD data
1-bit data
1-bit data
Upper Lower
Upper Lower
Figure 2.5 General Register Data Formats (1)