r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 561

• Manufacturer Part Number: r8a77850anbg
• Description: Renesas 32-bit Risc Microcomputer Superh? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

Figure 12.9 shows waveforms for 32-byte reading when the bus width is set to 32 bits. In this case,
the READ command is issued twice. In this example, read access processing is executed for bank
A after the ACT command is issued, but when there is a page hit, access begins with the issue of
the READ command.
Example of CL = 3
MCK0,
MCK1
MCKE
MCS
MRAS
MCAS
MWE
MA[14:11]
MA[9:0]
MA[10]
MBA[2:0]
MDQS[3:0]
MDM[3:0]
MDQ[31:0]
SDRAM
command
bank A
ACT
Valid
Valid
Valid
Figure 12.8 Waveforms for 1/2/4/8/16-Byte Reading
Invalid
Invalid
Invalid
(When the Bus Width Is Set to 32 Bits)
High level
bank A
READ
Valid
Valid
Valid
Invalid
Invalid
Read data
Invalid
Invalid
Invalid
Rev.1.00 Jan. 10, 2008 Page 531 of 1658
12. DDR2-SDRAM Interface (DBSC2)
Invalid
REJ09B0261-0100