p2125vps20 Renesas Electronics Corporation., p2125vps20 Datasheet - Page 97

• Manufacturer Part Number: p2125vps20
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

3.2.2
SYSCR selects system pin function, monitors a reset source, selects the interrupt control mode and
the detection edge for NMI, enables or disables access to the on-chip peripheral module registers,
and enables or disables the on-chip RAM address space.
Bit
7
6
5
4
3
2
Bit Name
—
IOSE
INTM1
INTM0
XRST
NMIEG
System Control Register (SYSCR)
Initial
Value
0
0
0
0
1
0
R/W
R
R/W
R
R/W
R
R/W
Description
Reserved
The initial value should not be changed.
IOS Enable
Controls AS/IOS pin function in extended mode.
0: AS pin
1: IOS pin
Interrupt Control Select Mode 1, 0
These bits select the interrupt control mode of the interrupt
controller.
For details on the interrupt control modes, see section 5.6,
Interrupt Control Modes and Interrupt Operation.
00: Interrupt control mode 0
01: Interrupt control mode 1
10: Setting prohibited
11: Setting prohibited
External Reset
Indicates the reset source. A reset is caused by an external
reset input, or when the watchdog timer overflows.
0: A reset is caused when the watchdog timer overflows
1: A reset is caused by an external reset
NMI Edge Select
Selects the valid edge of the NMI interrupt input.
0: An interrupt is requested at the falling edge of NMI input
1: An interrupt is requested at the rising edge of NMI input
Low output when accessing the external area.
Low output when accessing the specified address from
H'(FF)F000 to H'(FF)F7FF
Rev. 1.00 Sep. 21, 2006 Page 59 of 658
Section 3 MCU Operating Modes
REJ09B0310-0100