HD6412332 RENESAS [Renesas Technology Corp], HD6412332 Datasheet - Page 208

• Manufacturer Part Number: HD6412332
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

• RAS up mode
Rev.4.00 Sep. 07, 2007 Page 178 of 1210
REJ09B0245-0400
A
CS
CAS, LCAS
D
Note: n = 2 to 5
To select RAS up mode, clear the RCDM bit in MCR to 0. Each time access to DRAM space
is interrupted and another space is accessed, the RAS signal goes high again. Burst operation is
only performed if DRAM space is continuous. Figure 6.22 shows an example of the timing in
RAS up mode. Note that in burst ROM space access, the RAS signal does not return to the
high level.
φ
23
15
n
to A
to D
(RAS)
0
0
Figure 6.22 Example of Operation Timing in RAS Up Mode
T
p
DRAM access
T
r
T
c1
T
c2
DRAM access
T
c1
T
c2
space access
T
External
1
T
2