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SH7619 Datasheet, PDF (195/836 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7619 Series
Section 7 Bus State Controller (BSC)
7.5.5 SDRAM Interface
SDRAM Direct Connection: The SDRAM that can be connected to this LSI is a product that has
11/12/13 bits of row address, 8/9/10 bits of column address, 4 or less banks, and uses the A10 pin
for setting precharge mode in read and write command cycles.
The control signals for direct connection of SDRAM are RAS, CAS, RD/WR, DQMUU,
DQMUL, DQMLU, DQMLL, CKE, and CS3. Signals other than CKE are valid when CS3 is
asserted. SDRAM can be connected to area 2. The data bus width of the area that is connected to
SDRAM can be set to 16 bits or 32 bits.
Burst read/single write (burst length 1) and burst read/burst write (burst length 1) are supported as
the SDRAM operating mode.
Commands for SDRAM can be specified by RAS, CAS, RD/WR, and specific address signals.
These commands are shown below.
• NOP
• Auto-refreshing (REF)
• Self-refreshing (SELF)
• All banks precharge (PALL)
• Specified bank precharge (PRE)
• Bank active (ACTV)
• Read (READ)
• Read with precharge (READA)
• Write (WRIT)
• Write with precharge (WRITA)
• Write mode register (MRS)
The byte to be accessed is specified by DQMUU, DQMUL, DQMLU and DQMLL. Reading or
writing is performed for a byte whose corresponding DQMxx is low. For details on the
relationship between DQMxx and the byte to be accessed, refer to section 7.5.1, Endian/Access
Size and Data Alignment.
Rev. 5.00 Mar. 15, 2007 Page 157 of 794
REJ09B0237-0500