HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 492

• Manufacturer Part Number: HD6417021
• Description: SuperH RISC engine
• Manufacturer: Hitachi Semiconductor

HITACHI 484
WRH, WRL,
WRH, WRL,
Notes: 1.
AD15–AD0
AD15–AD0
DPH, DPL
DPH, DPL
RD(Read)
RD(Write)
A21–A0
DACK0
DACK1
DACK0
DACK1
(Read)
(Read)
(Read)
(Write)
(Write)
(Write)
(Write)
RAS
CAS
CK
2.
3.
4.
5.
Figure 19.27 DRAM Bus Cycle: (Long Pitch, High-Speed Page Mode)
For t
For t
For t
t
t
RDH
RDH
CAC2
ACC2
RAC2
is measured from A21–A0 or CAS, whichever is negated first.
is measured from A21–A0, RAS, or CAS whichever is negated first.
T
p
, use t
, use t
, use t
t
t
AD
RAC2
cyc
cyc
cyc
T
r
*
t
Row
RASD1
3
(n + 1) – 35 instead of t
(n + 2) – 44 instead of t
(n + 2.5) – 35 instead of t
t
t
AD
RDD
T
c1
t
t
t
t
t
t
ACC2
WSD1
WDD1
DACD1
WPDD1
DACD3
t
Column
CASD2
*
2
t
CAC2
T
c2
t
t
WSD2
DACD3
*
t
t
RDS
DACD2
1
cyc
cyc
t
WPDH
cyc
t
t
RSD
WDH
t
t
CASD3
RDH
T
(n + 1) – t
(n + 2) – t
c1
t
(n + 2.5) – t
t
t
t
t
*
WSD1
WDD1
DACD3
WPDD1
DACD1
4
Column
CASD2
AD
T
c2
t
t
– t
WSD2
DACD3
RASD1
RDS
– t
t
t
t
WPDH
RDS
DACD2
WDH
.
t
t
– t
t
CASD3
RDH
RASD2
.
RDS
*
5
.