r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 575

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

MCK
MCKE
Command
Data
Terminating
resistor
in SDRAM
MODT
As shown in the above figure, when CL is 4, the effective ODT control signal
(MODT) to the SDRAM can be asserted at the same timing as the issue of the
WRITE command. If CL is 5 or greater, MODT is asserted after the issue of the
WRITE command. However, if CL is 3 or less, MODT needs to be asserted
before the issue of the WRITE command, which is not supported by this LSI.
Figure 12.21 ODT Control Signal when CL = 4
write
tAOND
= 2 cycles
High level
3 cycles
for product
with CL = 4
Resistor ON
tAOFD
= 2.5 cycles
Rev.1.00 Jan. 10, 2008 Page 545 of 1658
12. DDR2-SDRAM Interface (DBSC2)
REJ09B0261-0100