Datasheet

Section 3 MCU Operating Modes
Rev. 4.00 Sep 27, 2006 page 86 of 1130
REJ09B0327-0400
Bit 6—IOS Enable (IOSE): Controls the function of the AS/IOS pin in expanded mode.
Bit 6
IOSE Description
0 The AS/IOS pin functions as the address strobe pin (AS)
(Low output when accessing an external area) (Initial value)
1 The AS/IOS pin functions as the I/O strobe pin (IOS)
(Low output when accessing a specified address from H'(FF)F000 to H'(FF)FE4F)
*
Note: * In the H8S/2148 F-ZTAT A-mask version and H8S/2147 F-ZTAT A-mask version, the
address range is from H'(FF)F000 to H'(FF)F7FF.
Bit 3—External Reset (XRST): Indicates the reset source. When the watchdog timer is used, a
reset can be generated by watchdog timer overflow as well as by external reset input. XRST is a
read-only bit. It is set to 1 by an external reset and cleared to 0 by watchdog timer overflow.
Bit 3
XRST Description
0 A reset is generated by watchdog timer overflow
1 A reset is generated by an external reset (Initial value)
Bit 1—Host Interface Enable (HIE): This bit controls CPU access to the host interface data
registers and control registers (HICR, IDR1, ODR1, STR1, IDR2, ODR2, and STR2), the
keyboard controller and MOS input pull-up control registers (KMIMR, KMPCR, and KMIMRA),
the 8-bit timer (channel X and Y) data registers and control registers (TCRX/TCRY,
TCSRX/TCSRY, TICRR/TCORAY, TICRF/TCORBY, TCNTX/TCNTY, TCORC/TISR,
TCORAX, and TCORBX), and the timer connection control registers (TCONRI, TCONRO,
TCONRS, and SEDGR).
Bit 1
HIE Description
0 In areas H'(FF)FFF0 to H'(FF)FFF7 and H'(FF)FFFC to H'(FF)FFFF,
CPU access to 8-bit timer (channel X and Y) data registers and control
registers, and timer connection control registers, is permitted
(Initial value)
1 In areas H'(FF)FFF0 to H'(FF)FFF7 and H'(FF)FFFC to H'(FF)FFFF,
CPU access to host interface data registers and control registers, and
keyboard controller and MOS input pull-up control registers, is permitted