HD6412332 RENESAS [Renesas Technology Corp], HD6412332 Datasheet - Page 174

• Manufacturer Part Number: HD6412332
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

6.2.6
MCR is an 8-bit readable/writable register that selects the DRAM strobe control method, number
of precharge cycles, access mode, address multiplexing shift size, and the number of wait states
inserted during refreshing, when areas 2 to 5 are designated as DRAM interface areas.
MCR is initialized to H'00 by a reset, and in hardware standby mode. It is not initialized in
software standby mode.
Bit 7—TP Cycle Control (TPC): Selects whether a 1-state or 2-state precharge cycle (T
used when areas 2 to 5 designated as DRAM space are accessed.
Bit 7
TPC
0
1
Bit 6—Burst Access Enable (BE): Selects enabling or disabling of burst access to areas 2 to 5
designated as DRAM space. DRAM space burst access is performed in fast page mode.
Bit 6
BE
0
1
Bit 5—RAS Down Mode (RCDM): When areas 2 to 5 are designated as DRAM space and
access to DRAM is interrupted, RCDM selects whether the RAS signal is held low while waiting
for the next DRAM access (RAS down mode), or is driven high again (RAS up mode).
Bit 5
RCDM
0
1
Rev.4.00 Sep. 07, 2007 Page 144 of 1210
REJ09B0245-0400
Bit
Initial value :
R/W
Memory Control Register (MCR)
:
:
Description
1-state precharge cycle is inserted
2-state precharge cycle is inserted
Description
Burst disabled (always full access)
DRAM space access performed in fast page mode
Description
RAS up mode selected for DRAM interface
RAS down mode selected for DRAM interface
TPC
R/W
7
0
R/W
BE
6
0
RCDM
R/W
5
0
R/W
—
4
0
MXC1
R/W
0
3
MXC0
R/W
2
0
RLW1
R/W
1
0
(Initial value)
(Initial value)
(Initial value)
P
) is to be
RLW0
R/W
0
0