r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 573

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

Figure 12.20 is an example of a case in which, after issuing a REF command, a READ request is
issued. In order to issue the ACT commend after issuing the REF command, the DBSC2 waits for
a time stipulated by tRFC.
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
REF
tRFC
= 6 cycles
Invalid
Invalid
Invalid
High level
Figure 12.20 tRFC
bank
ACT
Invalid
Invalid
any
Valid
Valid
Valid
Invalid
Invalid
Invalid
Rev.1.00 Jan. 10, 2008 Page 543 of 1658
12. DDR2-SDRAM Interface (DBSC2)
READ
bank
any
Valid
Valid
Valid
Invalid
Invalid
Invalid
REJ09B0261-0100