Register Descriptions; Mode Control Register (Mdcr); Bus Control Register L (Bcrl) - Renesas H8S Series Hardware Manual

19.2

Register Descriptions

19.2.1

Mode Control Register (MDCR)

Bit : 7
—
Initial value : 1
R/W : —
Note: * Determined by pins MD
MDCR is an 8-bit read-only register that indicates the current operating mode of the H8S/2357 Group.
Bit 7—Reserved: This bit cannot be modified and is always read as 1.
Bits 6 to 3—Reserved: These bits cannot be modified and are always read as 0.
Bits 2 to 0—Mode Select 2 to 0 (MDS2 to MDS0): These bits indicate the input levels at pins MD
operating mode). Bits MDS
written to. The mode pin (MD
canceled by a power-on reset, but are retained after a manual reset*.
Note: * Manual reset is only supported in the H8S/2357 ZTAT.
19.2.2

Bus Control Register L (BCRL)

Bit : 7
BRLE
Initial value : 0
R/W : R/W
Enabling or disabling of part of the H8S/2357's on-chip ROM area can be selected by means of the EAE bit in BCRL.
For details of the other bits in BCRL, see section 6.2.5, Bus Control Register L (BCRL).
Bit 5—External Address Enable (EAE): Selects whether addresses H'010000 to H'01FFFF*
or external addresses.
Bit 5
EAE
0
1
Notes: 1. Reserved areas should not be accessed.
2. Addresses H'010000 to H'01FFFF are in the H8S/2357. Addresses H'010000 to H'03FFFF are in the H8S/2398.
Rev.6.00 Oct.28.2004 page 564 of 1016
REJ09B0138-0600H
6 5
— —
0 0
— —
to MD .
2 0
to MDS correspond to pins MD
2 0
to MD ) input levels are latched into these bits when MDCR is read. These latches are
2 0
6 5
BREQOE EAE
0 1
R/W R/W
Description
Addresses H'010000 to H'01FFFF*
Addresses H'010000 to H'01FFFF*
mode)
1
or a reserved area* (single-chip mode).
4 3
— — MDS2
0 0 —*
— —
to MD . MDS2 to MDS0 are read-only bits, and cannot be
2 0
4 3
LCASS DDS —
1 1
R/W R/W R/W
2
are in on-chip ROM
2
are external addresses (external expansion
2 1 0
MDS1 MDS0
—* —*
R R R
2 1 0
WDBE WAITE
1 0 0
R/W R/W
2
are to be internal addresses
to MD (the current
2 0
(Initial value)