ETC HD6417709A

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TM
Hitachi SuperH RISC Engine
SH-3, SH3-DSP
SDRAM Interface
Application Notes
Application Notes ADE-502-074
Rev. 1.0
04/09/02
Hitachi, Ltd.
Rev. 1.0, 02/02, page ii of vi
Cautions
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4. Design your application so that the product is used within the ranges guaranteed by Hitachi
particularly for maximum rating, operating supply voltage range, heat radiation characteristics,
installation conditions and other characteristics. Hitachi bears no responsibility for failure or
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6. No one is permitted to reproduce or duplicate, in any form, the whole or part of this document
without written approval from Hitachi.
7. Contact Hitachi’s sales office for any questions regarding this document or Hitachi
semiconductor products.
Rev. 1.0, 02/02, page iii of vi
Preface
TM
The SuperH RISC engine microcomputer is new generation RISC microcomputer that provides
high-performance operations using a RISC-type CPU. This microcomputer also incorporates
peripheral functions required for system configuration and achieves low-power consumption that
is essential for all microcomputer application devices.
This SH-3, SH3-DSP SDRAM Interface Application Notes can be used as a reference for user
system hardware design.
This application notes provides examples of SH-3 and SH3-DSP microcomputer interface with
external memory (SDRAM).
Note that althrough the operations of task examples provided in this application notes have been
checked by Hitachi, Ltd., it is advised that user check the operation of these task exanples prior to
using the tasks in the user system.
Note: SuperH
TM
is a registered trademark of Hitachi, Ltd.
Rev. 1.0, 02/02, page iv of vi
Contents
Section 1 How to Use the Application Notes ....................................................1
1.1
Configuration of SDRAM Interface Examples .................................................................1
Section 2 SDRAM Interface Examples ..............................................................3
2.1
2.2
2.3
SH7709A/SH7729 to SDRAM Interface Examples..........................................................3
2.1.1 Synchronous DRAM Direct Connection (SH7709A/SH7729) ............................3
2.1.2 HM5225165ATT-A6 (4 Mwords x 16 bits x 4 banks).........................................4
2.1.3 HM5212165DTD-B60 (2 Mwords x 16 bits x 4 banks).......................................7
2.1.4 HM5264165TT-B60 (1 Mword x 16 bits x 4 banks) ...........................................10
2.1.5 Power-On Sequence (SH7709A/SH7729) ...........................................................13
SH7709 and SDRAM Interface Examples ........................................................................14
2.2.1 Synchronous DRAM Direct Connection (SH7709) .............................................14
2.2.2 HM5212165D-B60 (2 Mwords x 16 bits x 4 banks)............................................16
2.2.3 HM5264165TT-B60 (1 Mword x 16 bits x 4 banks) ...........................................18
2.2.4 Power-On Sequence (SH7709) ............................................................................20
SH7708R and SDRAM Interface Examples......................................................................21
2.3.1 Synchronous DRAM Direct Connection (SH7708R)...........................................21
2.3.2 HM5212165D-B60 (2 Mwords x 16 bits x 4 banks)............................................22
2.3.3 HM5264165-B60 (1 Mword x 16 bits x 4 banks) ................................................24
2.3.4 Power-On Sequence (SH7708R)..........................................................................26
Rev. 1.0, 02/02, Page v of vi
Rev. 1.0, 02/02, page vi of vi
Section 1 How to Use the Application Notes
1.1
Configuration of SDRAM Interface Examples
The SDRAM interface examples (section 2) in this application notes consists of the following
subsections to describe the SDRAM interface method.
• SDRAM interface examples in this application notes:
 Bus state controller (BSC) settings
This subsection describes the BSC settings when SDRAM is connected.
 Interface circuit diagram
This subsection shows SDRAM interface circuit examples.
Note that this application notes describes the SDRAM interfaces based on the MCU and SDRAM
types summarized below.
MCU
SDRAM
SH7709A/SH7729
HM5225165ATT-A6
HM5212165DTD-B60
HM5264165TT-B60
SH7709
HM5212165D-B60
HM5264165TT-B60
SH7708R
HM5212165D-B60
HM5264165-B60
Rev. 1.0, 02/02, page 1 of 26
Rev. 1.0, 02/02, page 2 of 26
Section 2 SDRAM Interface Examples
2.1
SH7709A/SH7729 to SDRAM Interface Examples
2.1.1
Synchronous DRAM Direct Connection (SH7709A/SH7729)
Synchronous DRAM can be selected via the &6 signal, and can be connected to areas 2 and 3 of
the physical address space in the SH7709A or SH7729 by using common control signals such as
5$6. When the memory type bits (DRAMTP2 to DRAMTP0) of BCR1 are set to 010, area 2 and
area 3 can be used as the normal memory area and synchronous DRAM area, respectively. When
the memory type bits (DRAMTP2 to DRAMTP0) of BCR1 are set to 011, both areas 2 and 3 can
be used as the synchronous DRAM area.
This LSI supports burst read/single write mode with burst length 1 as a synchronous DRAM
operating mode. The data bus width can be selected as either 16 bits or 32 bits. The burst enable
bit (BE) of MCR is ignored. In cache-fill/write-back cycles, 16-byte burst transfer is always
performed. In write-through area write cycles or non-cacheable area read/write cycles, only one
access is performed.
To connect this LSI to synchronous DRAM directly, the 5$66/, 5$668, &$6/, &$68,
RD/:5, &65 or &66, DQMUU, DQMUL, DQMLU, DQMLL, and CKE signals are used as
control signals. These interface control signals, except for &65 and &66, are common to each area.
In addition, the interface control signals other than CKE are valid and latched only when &65 or
&66 is asserted. Accordingly, synchronous DRAM can be connected in parallel to multiple areas.
The CKE signal is negated (brought low) only when self-refreshing is performed and the CKE
signal is normally asserted (brought high).
The 5$66/, 5$668, &$6/, and &$68 signal outputs are determined depending on whether the
address is in the upper or lower 32 Mbytes of each area. If the address is in the upper 32-Mbyte
area (area 2: H'0A000000 to H'0BFFFFFF, area 3: H'0E000000 to H'0FFFFFFF), 5$668 and
&$68 are output. If it is in the lower 32-Mbyte area (area 2: H'08000000 to H'09FFFFFF, area 3:
H'0C000000 to H'0DFFFFFF), 5$66/ and &$6/ are output. In refresh cycles and mode-register
write cycles, 5$668 and 5$66/ or &$68 and &$6/ are output.
The 5$66/, 5$668, &$6/, &$68 and RD/:5 signals and specific address signals specify a
command for synchronous DRAM. The synchronous DRAM commands are NOP, auto-refresh
(REF), self-refresh (SELF), precharge all banks (PALL), row address strobe bank active (ACVT),
read (READ), read with precharge (READA), write (WRIT), write with precharge (WRITA), and
mode register setting (MRS).
Rev. 1.0, 02/02, page 3 of 26
Byte specification is performed by DQMUU, DQMUL, DQMLU, and DQMLL. A read/write is
performed for the byte for which the corresponding DQM is low. In big-endian mode, DQMUU
specifies an access to address 4n, and DQMLL specifies an access to address 4n + 3. In littleendian mode, DQMUU specifies an access to address 4n + 3, and DQMLL specifies an access to
address 4n.
2.1.2
HM5225165ATT-A6 (4 Mwords × 16 bits × 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5225165ATT-A6) are connected
to area 3 of the SH7709A or SH7729 via a 16-bit bus, the bus state controller (BSC) must be
specified as summarized below. Table 2.1 lists the BSC register settings.
Note that the interface between SDRAM and the SH7709A or SH7729 is performed with bus
clock = 66 MHz, CL = 2, TPC = 2, RCD = 2, TRWL = 1, and TRAS = 4.
Rev. 1.0, 02/02, page 4 of 26
Table 2.1 BSC Register Settings (HM5225165ATT-A6)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FF0
H’FFFFFF62
16
H’3FB0
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3FF3
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’522C
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A57C
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR

H’FFFFD000 to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
Write any value
in address
H’FFFFE440*
H’FFFFE000 to
H’FFFFEFFF
MCS0 control register
MCSCR0
H’0000
H’FFFFFF50
16
Need not be set
MCS1 control register
MCSCR1
H’0000
H’FFFFFF52
16
Need not be set
MCS2 control register
MCSCR2
H’0000
H’FFFFFF54
16
Need not be set
MCS3 control register
MCSCR3
H’0000
H’FFFFFF56
16
Need not be set
MCS4 control register
MCSCR4
H’0000
H’FFFFFF58
16
Need not be set
MCS5 control register
MCSCR5
H’0000
H’FFFFFF5A
16
Need not be set
MCS6 control register
MCSCR6
H’0000
H’FFFFFF5C
16
Need not be set
MCS7 control register
MCSCR7
H’0000
H’FFFFFF5E
16
Need not be set
Note:
Bits not related to this interface example show initial values. All register settings must be
checked according to the user system.
* In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 5 of 26
Interface Circuit Diagram: Figure 2.1 shows an interface circuit for the case in which area 3 of
the SH7709A or SH7729 is connected to SDRAM (HM5225165ATT-A6) via a 16-bit bus.
HM5225165ATT-A6
SH7709A/SH7729
A24
A14
A13
..
..
A1
CKIO
CKE
..
..
..
..
2
BA1
BA0
A12
..
..
A0
CLK
CKE
3.3V
RD/
DQMLU
DQMLL
D15
..
..
D0
..
..
..
..
..
..
DQMU
DQML
DQ15
..
..
DQ0
VCC
VCCQ
VSS
VSSQ
GND
BA1
BA0
A12
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
Note: The address multiplex bits (AMX) of MCR must be specified as AMX [2:0]=101.
Figure 2.1 Interface between SDRAM (HM5225165ATT-A6) and SH7709A or SH7729
Rev. 1.0, 02/02, page 6 of 26
2.1.3
HM5212165DTD-B60 (2 Mwords × 16 bits × 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5212165DTD-B60) are
connected to area 3 of the SH7709A or SH7729 via a 32-bit bus, the bus state controller (BSC)
must be specified as summarized below. Table 2.2 lists the BSC register settings.
Note that the interface between SDRAM and the SH7709A or SH7729 is performed with bus
clock = 66 MHz, CL = 2, TPC = 2, RCD = 2, TRWL = 1, and TRAS = 4.
Rev. 1.0, 02/02, page 7 of 26
Table 2.2 BSC Register Settings (HM5212165DTD-B60)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FF0
H’FFFFFF62
16
H’3FF0
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3FF3
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’522C
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A5F8
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR

H’FFFFD000 to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
Write any value
in address
H’FFFFE880*
H’FFFFE000 to
H’FFFFEFFF
MCS0 control register
MCSCR0
H’0000
H’FFFFFF50
16
Need not be set
MCS1 control register
MCSCR1
H’0000
H’FFFFFF52
16
Need not be set
MCS2 control register
MCSCR2
H’0000
H’FFFFFF54
16
Need not be set
MCS3 control register
MCSCR3
H’0000
H’FFFFFF56
16
Need not be set
MCS4 control register
MCSCR4
H’0000
H’FFFFFF58
16
Need not be set
MCS5 control register
MCSCR5
H’0000
H’FFFFFF5A
16
Need not be set
MCS6 control register
MCSCR6
H’0000
H’FFFFFF5C
16
Need not be set
MCS7 control register
MCSCR7
H’0000
H’FFFFFF5E
16
Need not be set
Note: * In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 8 of 26
Interface Circuit Diagram: Figure 2.2 shows an interface circuit for the case in which area 3 of
the SH7709A or SH7729 is connected to SDRAM (HM5212165DTD-B60) via a 32-bit bus.
HM5212165DTD-B60
SH7709/SH7729
A15
..
..
A2
CKIO
CKE
..
..
..
..
2
A13
..
..
A0
CLK
CKE
3.3V
RD/
DQMUU
DQMUL
D31
..
..
D16
DQMLU
DQMLL
D15
..
..
D0
..
..
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
..
..
..
..
A13
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
Note: The address multiplex bits (AMX) of MCR must be specified as AMX [2:0]=101.
Figure 2.2 Interface between SDRAM (HM5212165DTD-B60) and SH7709A or SH7729
Rev. 1.0, 02/02, page 9 of 26
2.1.4
HM5264165TT-B60 (1 Mword × 16 bits × 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5264165TT-B60) are connected
to area 3 of the SH7709A or SH7729 via a 32-bit bus, the bus state controller (BSC) must be
specified as summarized below. Table 2.3 lists the BSC register settings.
Note that the interface between SDRAM and the SH7709A or SH7729 is performed with bus
clock = 66 MHz, CL = 2, TPC = 2, RCD = 3, TRWL = 1, and TRAS = 4.
Rev. 1.0, 02/02, page 10 of 26
Table 2.3 BSC Register Settings (HM5264165TT-B60)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FF0
H’FFFFFF62
16
H’3FF0
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3FF3
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’6224
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A5F8
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR

H’FFFFD000 to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
Write any value
in address
H’FFFFE880*
H’FFFFE000 to
H’FFFFEFFF
MCS0 control register
MCSCR0
H’0000
H’FFFFFF50
16
Need not be set
MCS1 control register
MCSCR1
H’0000
H’FFFFFF52
16
Need not be set
MCS2 control register
MCSCR2
H’0000
H’FFFFFF54
16
Need not be set
MCS3 control register
MCSCR3
H’0000
H’FFFFFF56
16
Need not be set
MCS4 control register
MCSCR4
H’0000
H’FFFFFF58
16
Need not be set
MCS5 control register
MCSCR5
H’0000
H’FFFFFF5A
16
Need not be set
MCS6 control register
MCSCR6
H’0000
H’FFFFFF5C
16
Need not be set
MCS7 control register
MCSCR7
H’0000
H’FFFFFF5E
16
Need not be set
Note: * In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 11 of 26
Interface Circuit Diagram: Figure 2.3 shows an interface circuit for the case in which area 3 of
the SH7709A or SH7729 is connected to SDRAM (HM5264165TT-B60) via a 32-bit bus.
HM5264165TT-B60
SH7709/SH7729
A15
..
..
A2
CKIO
CKE
..
..
..
..
2
A13
..
..
A0
CLK
CKE
3.3V
RD/
DQMUU
DQMUL
D31
..
..
D16
DQMLU
DQMLL
D15
..
..
D0
..
..
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
..
..
..
..
A13
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
Note: The address multiplex bits (AMX) of MCR must be specified as AMX [2:0]=100.
Figure 2.3 Interface between SDRAM (HM5264165TT-B60) and SH7709A or SH7729
Rev. 1.0, 02/02, page 12 of 26
2.1.5
Power-On Sequence (SH7709A/SH7729)
To use the synchronous DRAM, specify modes after power-on. To initialize the synchronous
DRAM correctly, first specify the bus state controller registers and then specify the synchronous
DRAM mode register. When specifying the synchronous DRAM mode register, the address
signal value is latched depending on the combination of 5$6, &$6, and RD/:5 signals. In this
case, the bus state controller functions as follows. To write a designated value X to the DRAM
mode register, write data to address H’FFFFD000 + X for area 2 of synchronous DRAM and write
data to H’FFFFE000 + X for area 3 of synchronous DRAM. At this time, data written at addresses
H’FFFFD000 + X and H’FFFFE000 + X is ignored and the DRAM mode register is written in
byte units.
To specify burst read/single write, CAS latency as 1 to 3, sequential as lap type, and burst length
as 1, write arbitrary data in byte units to the addresses listed below.
32-bit bus width
16-bit bus width
CAS latency 1
Area 2
FFFD840
Area 3
FFFE840
CAS latency 2
FFFD880
FFFE880
CAS latency 3
FFFD8C0
FFFE8C0
CAS latency 1
Area 2
FFFD420
Area 3
FFFE420
CAS latency 2
FFFD440
FFFE440
CAS latency 3
FFFD460
FFFE460
By writing data to address H’FFFD000 + X or address H’FFFE000 + X, the precharge all banks
command (PALL) is first issued at cycle TRp1, and a mode register write command is issued at
the following cycle TMw1. The address signals when a mode register write command is issued are
as follows.
32-bit bus width
16-bit bus width
A15 to A9
0000100 (Burst read and single write)
A8 to A6
CAS latency
A5
0 (Burst type = sequential)
A4 to A2
000 (Burst length 1)
A14 to A8
0000100 (Burst read and single write)
A7 to A5
CAS latency
A4
0 (Burst type = sequential)
A3 to A1
000 (Burst length 1)
Rev. 1.0, 02/02, page 13 of 26
Before specifying the mode register, 100 µs of idle time (differs depending on the memory
manufacturer) required for synchronous DRAM must be ensured after power-on. If the pulse
width of the reset signal is longer than this idle time, the mode register can be specified
immediately after power-on. In addition, dummy auto-refresh cycles must be executed for the
number of times specified by the manufacturer (normally 8 times) or more. Dummy auto-refresh
cycles are normally specified to be executed automatically during initializations after auto-refresh
setting. However, to ensure execution of the auto-refresh cycles, the time intervals between refresh
requests must be shortened while the dummy cycles are executed. Note that the auto-refresh cycles
must be executed in order to initialize the synchronous DRAM internal address counter because
the synchronous DRAM internal address counter cannot be initialized by a normal read or write
access.
2.2
SH7709 and SDRAM Interface Examples
2.2.1
Synchronous DRAM Direct Connection (SH7709)
Synchronous DRAM can be selected via the &6 signal, and can be connected to areas 2 and 3 of
the physical address space in the SH7709A or SH7729 by using common control signals such as
RAS. When the memory type bits (DRAMTP2 to DRAMTP0) of BCR1 are set to 010, area 2 and
area 3 can be used as the normal memory area and synchronous DRAM area, respectively. When
the memory type bits (DRAMTP2 to DRAMTP0) of BCR1 are set to 011, both areas 2 and 3 can
be used as the synchronous DRAM area.
This LSI supports burst read/single write mode with burst length 1 as a synchronous DRAM
operating mode. The data bus width can be selected as either 16 bits or 32 bits. The burst enable
bit (BE) of MCR is ignored. In cache-fill/write-back cycles, 16-byte burst transfer is always
performed. In write-through area write cycles or non-cacheable area read/write cycles, only one
access is performed.
To connect this LSI to synchronous DRAM directly, the 5$66/, 5$668, &$6/, &$68,
RD/:5, &65 or &66, DQMUU, DQMUL, DQMLU, DQMLL, and CKE signals are used as
control signals. These interface control signals, except for &65 and &66, are common to each area.
In addition, the interface control signals other than CKE are valid and latched only when &65 or
&66 is asserted. Accordingly, synchronous DRAM can be connected in parallel to multiple areas.
The CKE signal is negated (brought low) only when self-refreshing is performed and the CKE
signal is normally asserted (brought high).
The 5$66/, 5$668, &$6/, and &$68 signal outputs are determined depending on whether the
address is in the upper or lower 32 Mbytes of each area. If the address is in the upper 32-Mbyte
area (area 2: H'0A000000 to H'0BFFFFFF, area 3: H'0E000000 to H'0FFFFFFF), 5$668 and
&$68 are output. If it is in the lower 32-Mbyte area (area 2: H'08000000 to H'09FFFFFF, area 3:
H'0C000000 to H'0DFFFFFF), 5$66/ and &$6/ are output. In refresh cycles and mode-register
write cycles, 5$668 and 5$66/ or &$68 and &$6/ are output.
Rev. 1.0, 02/02, page 14 of 26
The 5$66/, 5$668, &$6/, &$68 and RD/:5 signals and specific address signals specify a
command for synchronous DRAM. The synchronous DRAM commands are NOP, auto-refresh
(REF), self-refresh (SELF), precharge all banks (PALL), row address strobe bank active (ACVT),
read (READ), read with precharge (READA), write (WRIT), write with precharge (WRITA), and
mode register setting (MRS).
Byte specification is performed by DQMUU, DQMUL, DQMLU, and DQMLL. A read/write is
performed for the byte for which the corresponding DQM is low. In big-endian mode, DQMUU
specifies an access to address 4n, and DQMLL specifies an access to address 4n + 3. In littleendian mode, DQMUU specifies an access to address 4n + 3, and DQMLL specifies an access to
address 4n.
Rev. 1.0, 02/02, page 15 of 26
2.2.2
HM5212165D-B60 (2 Mwords × 16 bits × 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5212165D-B60) are connected
to area 3 of the SH7709 via a 32-bit bus, the bus state controller (BSC) must be specified as
summarized below. Table 2.4 lists the BSC register settings.
Note that the interface between SDRAM and the SH7709 is performed with bus clock = 40 MHz,
CL = 2, TPC = 1, RCD = 1, TRWL = 1, and TRAS = 2.
Table 2.4 BSC Register Settings (HM5212165D-B60)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FF0
H’FFFFFF62
16
H’3FF0
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3F33
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’000C
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A54F
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR

H’FFFFD000 to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
H’FFFFE000 to
H’FFFFEFFF
Write any value
in address
H’FFFFE880*
Note: * In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 16 of 26
Interface Circuit Diagram: Figure 2.4 shows an interface circuit for the case in which area 3 of
the SH7709 is connected to SDRAM (HM5212165D-B60) via a 32-bit bus.
SH7709
A24
A23
A13
..
..
A2
CKIO
CKE
HM5212165D-B60
..
..
..
..
2
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
RD/
DQMUU
DQMUL
D31
..
..
D16
DQMLU
DQMLL
D15
..
..
D0
..
..
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
..
..
..
..
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
DQ0
VCC
VCCQ
VSS
VSSQ
GND
Note: Upper addresses of the SH7709, which are not multiplexed with other pin functions, are used for SDRAM
bank selection. In this interface example, A23 and A24 of the SH7709 are used. The address multiplex
bits (AMX) of MCR must be specified as AMX[1:0]=01. Note that only the upper or lower 32 Mbytes in a
64-Mbyte address space can be used.
Figure 2.4 Interface between SDRAM (HM5212165D-B60) and SH7709
Rev. 1.0, 02/02, page 17 of 26
2.2.3
HM5264165TT-B60 (1 Mword × 16 bits × 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5264165TT-B60) are connected
to area 3 of the SH7709 via a 32-bit bus, the bus state controller (BSC) must be specified as
summarized below. Table 2.5 lists the BSC register settings.
Note that the interface between SDRAM and the SH7709 is performed with bus clock = 40 MHz,
CL = 2, TPC = 1, RCD = 1, TRWL = 1, and TRAS = 2.
Table 2.5 BSC Register Settings (HM5264165TT-B60)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FF0
H’FFFFFF62
16
H’3FF0
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3F33
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’0004
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A54F
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR

H’FFFFD000 to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
H’FFFFE000 to
H’FFFFEFFF
Write any value
in address
H’FFFFE880*
Note: * In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 18 of 26
Interface Circuit Diagram: Figure 2.5 shows an interface circuit for the case in which area 3 of
the SH7709 is connected to SDRAM (HM5264165TT-B60) via a 32-bit bus.
HM5264165TT-B60
SH7709
A23
A22
A13
..
..
A2
CKIO
CKE
..
..
..
..
2
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
RD/
DQMUU
DQMUL
D31
..
..
D16
DQMLU
DQMLL
D15
..
..
..
..
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
..
..
D0
..
..
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
DQ0
VCC
VCCQ
VSS
VSSQ
GND
Note: Upper addresses of the SH7709, which are not multiplexed with other pin functions, are used for SDRAM
bank selection. In this interface example, A22 and A23 of the SH7709 are used. The address multiplex
bits (AMX) of MCR must be specified as AMX[1:0]=00. Note that only the upper or lower 32 Mbytes in a
64-Mbyte address space can be used.
Figure 2.5 Interface between SDRAM (HM5264165TT-B60) and SH7709
Rev. 1.0, 02/02, page 19 of 26
2.2.4
Power-On Sequence (SH7709)
To use the synchronous DRAM, specify modes after power-on. To initialize the synchronous
DRAM correctly, first specify the bus state controller registers and then specify the synchronous
DRAM mode register. When specifying the synchronous DRAM mode register, the address signal
value is latched depending on the combination of 5$6, &$6, and RD/:5 signals. In this case, the
bus state controller functions as follows. To write a designated value X to the DRAM mode
register, write data to address H’FFFFD000 + X for area 2 of synchronous DRAM and write data
to H’FFFFE000 + X for area 3 of synchronous DRAM. At this time, data written at addresses
H’FFFFD000 + X and H’FFFFE000 + X is ignored and the DRAM mode register is written in
byte units.
To specify burst read/single write, CAS latency as 1 to 3, sequential as lap type, and burst length
as 1, write arbitrary data in byte units to the addresses listed below.
CAS latency 1
Area 2
FFFD840
Area 3
FFFE840
CAS latency 2
FFFD880
FFFE880
CAS latency 3
FFFD8C0
FFFE8C0
By writing data to address H’FFFD000 + X or address H’FFFE000 + X, the precharge all banks
command (PALL) is first issued at cycle TRp1, and a mode register write command is issued at
the following cycle TMw1.
Before specifying the mode register, 100 µs of idle time (differs depending on the memory
manufacturer) required for synchronous DRAM must be ensured after power-on. If the pulse
width of the reset signal is longer than this idle time, the mode register can be specified
immediately after power-on. In addition, dummy auto-refresh cycles must be executed for the
number of times specified by the manufacturer (normally 8 times) or more. Dummy auto-refresh
cycles are normally specified to be executed automatically during initializations after auto-refresh
setting. However, to ensure execution of the auto-refresh cycles, the time intervals between refresh
requests must be shortened while the dummy cycles are executed. Note that the auto-refresh cycles
must be executed in order to initialize the synchronous DRAM internal address counter because
the synchronous DRAM internal address counter cannot be initialized by a normal read or write
access.
Rev. 1.0, 02/02, page 20 of 26
2.3
SH7708R and SDRAM Interface Examples
2.3.1
Synchronous DRAM Direct Connection (SH7708R)
Synchronous DRAM can be selected via the &6 signal, and can be connected to area 2 and area 3
of the physical space in the SH7708R by using common control signals such as 5$6. When the
memory type bits (DRAMTP2 to DRAMTP0) of BCR1 are set to 010, area 2 and area 3 are used
as the normal memory area and synchronous DRAM area, respectively. When the memory type
bits (DRAMTP2 to DRAMTP0) of BCR1 are set to 011, both areas 2 and 3 are used as the
synchronous DRAM area.
This LSI supports burst read/single write mode with burst length 1 as a synchronous DRAM
operating mode. The data bus width is fixed at 32 bits, and the size bit (SZ) of MCR must always
be set to 1. The burst enable bit (BE) of MCR is ignored. Accordingly, 16-byte burst transfer is
always performed in cache-fill/write-back cycles, and only one access is performed in writethrough area write cycles or non-cacheable area read/write cycles.
To connect this LSI to synchronous DRAM directly, the 5$66/,#5$668, &$6/,#&$68,
RD/:5,#&65#or#&66, DQMUU, DQMUL, DQMLU, DQMLL, and CKE signals are used as
control signals. These interface control signals, except for &65#and#&66/ are common to each area.
In addition, the interface control signals other than CKE are valid and latched only when &65#or
&66#is asserted. Accordingly, synchronous DRAM can be connected in parallel to multiple areas.
The CKE signal is negated (brought low) only when self-refreshing is performed and the CKE
signal is normally asserted (brought high).
The 5$66/,#5$668, &$6/,#&$68 and RD/:5 signals and specific address signals specify a
command for synchronous DRAM. The synchronous DRAM commands are NOP, auto-refresh
(REF), self-refresh (SELF), precharge all banks (PALL), row address strobe bank active (ACVT),
read (READ), read with precharge (READA), write (WRIT), write with precharge (WRITA), and
mode register setting (MRS).
Byte specification is performed by DQMUU, DQMUL, DQMLU, and DQMLL. A read/write is
performed for the byte for which the corresponding DQM is low. In big-endian mode, DQMUU
specifies an access to address 4n, and DQMLL specifies an access to address 4n + 3. In littleendian mode, DQMUU specifies an access to address 4n + 3, and DQMLL specifies an access to
address 4n.
Rev. 1.0, 02/02, page 21 of 26
2.3.2
HM5212165D-B60 (2 Mwords × 16 bits × 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5212165D-B60) are connected
to area 3 of the SH7708R via a 32-bit bus, the bus state controller (BSC) must be specified as
summarized below. Table 2.6 lists the BSC register settings.
Note that the interface between SDRAM and the SH7708R is performed with bus clock = 60
MHz, CL = 2, TPC = 1, RCD = 1, TRWL = 1, and TRAS = 2.
Table 2.6 BSC Register Settings (HM5212165D-B60)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FFC
H’FFFFFF62
16
H’3FFC
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3FFF
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’000C
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A5EB
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR
−
H’FFFFD000
to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
H’FFFFE000
to
H’FFFFEFFF
Write any value
in address
H’FFFFE880*
Note: * In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 22 of 26
Interface Circuit Diagram: Figure 2.6 shows an interface circuit for the case in which area 3 of
the SH7708R is connected to SDRAM (HM5212165D-B60) via a 32-bit bus.
SH7708R
A24
A23
A13
..
..
A2
CKIO
CKE
HM5212165D-B60
..
..
..
..
2
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
RD/
DQMUU
DQMUL
D31
..
..
D16
DQMLU
DQMLL
D15
..
..
D0
..
..
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
..
..
..
..
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
DQ0
VCC
VCCQ
VSS
VSSQ
GND
Note: Upper addresses of the SH7708R, which are not multiplexed with other pin functions, are used for SDRAM
bank selection. In this interface example, A23 and A24 of the SH7708R are used. The address multiplex
bits (AMX) of MCR must be specified as AMX[1:0]=01.
Figure 2.6 Interface between SDRAM (HM5212165D-B60) and SH7708R
Rev. 1.0, 02/02, page 23 of 26
2.3.3
HM5264165-B60 (1 Mword x 16 bits x 4 banks)
Bus State Controller (BSC) Settings: When two SDRAMs (HM5264165-B60) are connected to
area 3 of the SH7708R via a 32-bit bus, the bus state controller (BSC) must be specified as
summarized below. Table 2.7 lists the BSC register settings.
Note that the interface between SDRAM and the SH7708R is performed with bus clock = 60
MHz, CL = 2, TPC = 1, RCD = 1, TRWL = 1, and TRAS = 2.
Table 2.7 BSC Register Settings (HM5264165-B60)
Register Name
Abbr.
Initial
Value
Address
Access
Size
Setting Value
Bus control register 1
BCR1
H’0000
H’FFFFFF60
16
H’0008
Bus control register 2
BCR2
H’3FFC
H’FFFFFF62
16
H’3FFC
Wait state control register 1
WCR1
H’3FF3
H’FFFFFF64
16
H’3FFF
Wait state control register 2
WCR2
H’FFFF
H’FFFFFF66
16
H’FFDF
Individual memory control
register
MCR
H’0000
H’FFFFFF68
16
H’0004
DRAM control register
DCR
H’0000
H’FFFFFF6A
16
Need not be set
PCMCIA control register
PCR
H’0000
H’FFFFFF6C
16
Need not be set
Refresh timer control/status
register
RTCSR
H’0000
H’FFFFFF6E
16
H’A508
Refresh timer counter
RTCNT
H’0000
H’FFFFFF70
16
H’A500
Refresh time constant counter
RTCOR
H’0000
H’FFFFFF72
16
H’A582
Refresh count register
RFCR
H’0000
H’FFFFFF74
16
Need not be set
Bus control register 3
BCR3
H’0000
H’FFFFFF7E
16
Need not be set
Synchronous
DRAM mode
register
SDMR

H’FFFFD000
to
H’FFFFDFFF
8
Need not be set
Area 2
Area 3
H’FFFFE000
to
H’FFFFEFFF
Write any value
in address
H’FFFFE880*
Note: * In area 3, the SDMR address is determined by adding H’FFFFE000 to the desired value to
be set in SDMR. The desired value can be set in SDMR by writing any value in this
address.
Rev. 1.0, 02/02, page 24 of 26
Interface Circuit Diagram: Figure 2.7 shows an interface circuit for the case in which area 3 of
the SH7708R is connected to SDRAM (HM5264165-B60) via a 32-bit bus.
HM5264165-B60
SH7708R
A23
A22
A13
..
..
A2
CKIO
CKE
..
..
..
..
2
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
RD/
DQMUU
DQMUL
D31
..
..
D16
DQMLU
DQMLL
D15
..
..
D0
..
..
..
..
DQMU
DQML
DQ15
..
..
VCC
VCCQ
VSS
VSSQ
DQ0
GND
..
..
..
..
A13
A12
A11
..
..
A0
CLK
CKE
3.3V
..
..
DQMU
DQML
DQ15
..
..
DQ0
VCC
VCCQ
VSS
VSSQ
GND
Note: Upper addresses of the SH7708R, which are not multiplexed with other pin functions, are used for SDRAM
bank selection. In thisinterface example, A22 and A23 of the SH7708R are used. The address multiplex
bits (AMX) of MCR must be specified as AMX[1:0]=00.
Figure 2.7 Interface between SDRAM (HM5264165-B60) and SH7708R
Rev. 1.0, 02/02, page 25 of 26
2.3.4
Power-On Sequence (SH7708R)
To use the synchronous DRAM, specify modes after power-on. To initialize the synchronous
DRAM correctly, first specify the bus state controller registers and then specify the synchronous
DRAM mode register. When specifying the synchronous DRAM mode register, the address
signal value is latched depending on the combination of 5$6, &$6, and RD/:5 signals. In this
case, the bus state controller functions as follows. To write a designated value X to the DRAM
mode register, write data to address H’FFFFD000 + X for area 2 of synchronous DRAM and write
data to H’FFFFE000 + X for area 3 of synchronous DRAM. At this time, data written at addresses
H’FFFFD000 + X and H’FFFFE000 + X is ignored and the DRAM mode register is written in
byte units.
To specify burst read/single write, CAS latency as 1 to 3, sequential as lap type, and burst length
as 1, write arbitrary data in byte units to the addresses listed below.
CAS latency 1
Area 2
FFFD840
Area 3
FFFE840
CAS latency 2
FFFD880
FFFE880
CAS latency 3
FFFD8C0
FFFE8C0
By writing data to address H’FFFD000 + X or address H’FFFE000 + X, the precharge all banks
command (PALL) is first issued at cycle TRp1, and a mode register write command is issued at
the following cycle TMw1.
Before specifying the mode register, 100 µs of idle time (differs depending on the memory
manufacturer) required for synchronous DRAM must be ensured after power-on. If the pulse
width of the reset signal is longer than this idle time, the mode register can be specified
immediately after power-on. In addition, dummy auto-refresh cycles must be executed for the
number of times specified by the manufacturer (normally 8 times) or more. Dummy auto-refresh
cycles are normally specified to be executed automatically during initializations after auto-refresh
setting. However, to ensure execution of the auto-refresh cycles, the time intervals between refresh
requests must be shortened while the dummy cycles are executed. Note that the auto-refresh cycles
must be executed in order to initialize the synchronous DRAM internal address counter because
the synchronous DRAM internal address counter cannot be initialized by a normal read or write
access.
Rev. 1.0, 02/02, page 26 of 26
SH-3, SH3-DSP SDRAM Interface Applicarion Note
Publication Date: 1st Edition, February 2002
Published by:
Semiconductor & Integrated Circuits
Hitachi, Ltd.
Edited by:
Technical Documentation Group
Hitachi Kodaira Semiconductor Co., Ltd.
Copyright © Hitachi, Ltd., 2002. All rights reserved. Printed in Japan.