h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 106

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 3 MCU Operating Modes
Bit 3—NMI Edge Select (NMIEG): Selects the valid edge of the NMI interrupt input.
Bit 2— Reserved: Only 0 should be written to this bit.
Bit 1—Reserved: This bit is always read as 0 and cannot be modified.
Bit 0—RAM Enable (RAME): Enables or disables the on-chip RAM. The RAME bit is
initialized when the reset status is released. It is not initialized in software standby mode.
Note: When the DTC is used, the RAME bit must not be cleared to 0.
3.2.3
PFCR is an 8-bit readable-writeable register that performs address output control in extension
modes involving ROM.
PFCR is initialized to H'0D/H'00 by a reset and in the hardware standby mode.
Bits 7 to 4— Reserved: Only 0 should be written to these bits.
Bits 3 to 0—Address Output Enable 3 to 0 (AE3–AE0): These bits select enabling or disabling
of address outputs A8 to A23 in ROMless expanded mode and modes with ROM. When a pin is
enabled for address output, the address is output regardless of the corresponding DDR setting.
When a pin is disabled for address output, it becomes an output port when the corresponding DDR
bit is set to 1.
Rev. 5.00 Sep 22, 2005 page 80 of 1136
REJ09B0257-0500
Bit 3
NMIEG
0
1
Bit 0
RAME
0
1
Bit
Initial value
R/W
Pin Function Control Register (PFCR)
Description
An interrupt is requested at the falling edge of NMI input
An interrupt is requested at the rising edge of NMI input
Description
On-chip RAM is disabled
On-chip RAM is enabled
:
:
:
R/W
—
7
0
R/W
—
6
0
R/W
—
5
0
R/W
—
4
0
R/W
AE3
1/0
3
R/W
AE2
1/0
2
AE1
R/W
1
0
(Initial value)
(Initial value)
R/W
AE0
1/0
0