HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 476

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

HITACHI 468
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
2.
3.
4.
5.
Figure 19.14 DRAM Bus Cycle: (Long Pitch, High-Speed Page Mode)
CK
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
RAC2
AD
cyc
cyc
cyc
T
r
t
*
Row
RASD1
3
(n + 1) – 25 instead of t
(n + 2) – 30 instead of t
(n + 2.5) – 20 instead of t
t
t
AD
RDD
T
c1
t
t
t
t
t
t
WDD1
ACC2
DACD1
WSD1
WPDD1
DACD3
t
Column
CASD2
*
2
t
CAC2
T
c2
t
t
WSD2
DACD3
*
t
t
cyc
cyc
RDS
DACD2
1
cyc
t
WPDH
t
t
WDH
RSD
t
t
CASD3
RDH
(n + 1) – t
(n + 2) – t
T
(n + 2.5) – t
c1
t
t
t
t
t
*
WSD1
WDD1
DACD3
WPDD1
DACD1
4
Column
CASD2
AD
T
c2
– t
t
t
RASD1
DACD3
WSD2
RDS
– t
RDS
t
t
t
.
DACD2
WDH
WPDH
– t
t
t
t
CASD3
RDH
RASD2
RDS
.
*
5
.