r4f2426 Renesas Electronics Corporation., r4f2426 Datasheet - Page 322

• Manufacturer Part Number: r4f2426
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

Section 6 Bus Controller (BSC)
Setting the DRMI bit in DRACCR to 1 enables an idle cycle to be inserted in the case of
consecutive read and write operations in DRAM/continuous synchronous DRAM space burst
access. Figures 6.93 and 6.94 show an example of the timing for idle cycle insertion in the case of
consecutive read and write accesses to DRAM/continuous synchronous DRAM space.
Rev. 1.00 Sep. 19, 2008 Page 294 of 1270
REJ09B0466-0100
Figure 6.93 Example of Timing for Idle Cycle Insertion in Case of Consecutive Read and
UCAS, LCAS
Address bus
Note: n = 2 to 5
RASn (CSn)
WE (HWR)
Data bus
OE (RD)
Write Accesses to DRAM Space in RAS Down Mode
φ
T
p
DRAM space read
T
r
T
c1
T
c2
Idle cycle
DRAM space write
T
i
T
c1
T
c2