Datasheet

Section 2 CPU
Rev. 4.00 Sep 27, 2006 page 49 of 1130
REJ09B0327-0400
2.5 Data Formats
The 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 2.10 shows the data formats in general registers.
76543210 Don’t care
70
Don’t care 76543210
43
70
70
Don’t care
Upper digit Lower digit
LSB
MSB LSB
Data Type General Register Data Format
1-bit data
1-bit data
4-bit BCD data
4-bit BCD data
Byte data
Byte data
RnH
RnL
RnH
RnL
RnH
RnL
MSB
Don’t care
Upper digit
Lower digit
43
70
Don’t care
70
Don’t care
70
Figure 2.10 General Register Data Formats