m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 48

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

Fig. 3.1.2 Structure of processor mode register 0
3.1.2 Software reset
The microcomputer initializes pins, CPU, and SFR area just as in the case of hardware reset (Refer to
sections “3.2 Pin state” and “3.3 State of internal area.”) by writing “1” to the software reset bit. (See
Figure 3.1.2.)
After initialization is completed, the microcomputer performs “Internal processing sequence after reset.”
(Refer to section “3.4 Internal processing sequence after reset.”) After that, it executes a program
beginning with the address which has been set into the reset vector addresses (addresses FFFE
FFFF
Processor mode register 0
X: It may be either “0” or “1.”
16
).
Bit
0
1
2
3
4
5
6
7
Processor mode bits
Interrupt priority detection time
select bits
Software reset bit
Fix this bit to “0.”
Any of these bits may be either “0” or “1.”
Bit name
(Address 5E
7905 Group User’s Manual Rev.1.0
16
The microcomputer is reset by writing “1” to this
bit. The value is “0” at reading.
b5 b4
)
b1 b0
0 0 : Single-chip mode
0 1 : Do not select.
1 0 : Do not select.
1 1 : Do not select.
0 0 : 7 cycles of f
0 1 : 4 cycles of f
1 0 : 2 cycles of f
1 1 : Do not select.
sys
sys
sys
Function
b7 b6 b5 b4 b3 b2 b1 b0
0
3.1 Reset operation
At reset
X
0
0
0
1
0
0
0
0
X
RESET
R/W
WO
RW
RW
RW
RW
RW
RW
RW
0
0
16
and
3-3