h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 93

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

3.2.2
SYSCR selects saturating or non-saturating calculation for the MAC instruction, selects the
interrupt control mode and the detected edge for NMI, and enables or disables on-chip RAM.
Bit
7
6
5
4
3
2, 1
0
Bit Name
MACS

INTM1
INTM0
NMIEG

RAME
System Control Register (SYSCR)
Initial
Value
0
0
0
0
0
All 0
1
R/W
R/W

R/W
R/W
R/W

R/W
Descriptions
MAC Saturation
These bits select the control mode of the interrupt
controller. For details of the interrupt control modes, see
section 5.6, Interrupt Control Modes and Interrupt
Operation.
00: Interrupt control mode 0
01: Setting prohibited
10: Interrupt control mode 2
11: Setting prohibited
NMI Edge Select
RAM Enable
Selects either saturating or non-saturating calculation
for the MAC instruction.
0: Non-saturating calculation for the MAC instruction
1: Saturating calculation for the MAC instruction
Reserved
This bit is always read as 0 and cannot be modified.
Selects the valid edge of the NMI interrupt input.
0: An interrupt is requested at the falling edge of NMI
1: An interrupt is requested at the rising edge of NMI
Reserved
These bits are always read as 0 and cannot be
modified.
Enables or disables on-chip RAM. The RAME bit is
initialized when the reset status is released.
0: On-chip RAM is disabled
1: On-chip RAM is enabled
input
input
Rev. 2.00 Dec. 05, 2005 Page 55 of 724
Section 3 MCU Operating Modes
REJ09B0200-0200