h8s-2161b Renesas Electronics Corporation., h8s-2161b Datasheet - Page 91

• Manufacturer Part Number: h8s-2161b
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

2.4.5
The program counter (PC) among CPU internal registers is initialized when reset exception
handling loads a start address from a vector table. The trace (T) bit in EXR is cleared to 0, and the
interrupt mask (I) bits in CCR and EXR are set to 1. The other CCR bits and the general registers
are not initialized. Note that the stack pointer (ER7) is undefined. The stack pointer should
therefore be initialized by an MOV.L instruction executed immediately after a reset.
2.5
The H8S/2000 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
Figure 2.9 shows the data formats of general registers.
Initial Register Values
Data Formats
General Register Data Formats
Data Type
1-bit data
1-bit data
4-bit BCD data
4-bit BCD data
Byte data
Byte data
Figure 2.9 General Register Data Formats (1)
General Register
RnH
RnL
RnH
RnL
RnH
RnL
MSB
Data Image
7
7
7
7
Upper
6 5 4 3 2
Don’t care
Don’t care
Don’t care
4 3
Rev. 3.00 Mar 21, 2006 page 37 of 788
Lower
1 0
LSB
0
0
0
MSB
7
7
7
7
Upper
6 5 4 3 2
Don’t care
Don’t care
Don’t care
4 3
Lower
REJ09B0300-0300
Section 2 CPU
1 0
LSB
0
0
0