DSP56364D Motorola Inc, DSP56364D Datasheet - Page 46

• Manufacturer Part Number: DSP56364D
• Description: 24-Bit Audio Digital Signal Processor
• Manufacturer: Motorola Inc

Notes:
No.
Specifications
External Memory Expansion Port (Port A)
2-26
No.
131
132
133
134
135
136
137
138
139
140
Page mode cycle time for two consecutive
accesses of the same direction
Page mode cycle time for mixed (read and
write) accesses
CAS assertion to data valid (read)
Column address valid to data valid (read)
CAS deassertion to data not valid (read hold
time)
Last CAS assertion to RAS deassertion
Previous CAS deassertion to RAS deasser-
tion
CAS assertion pulse width
Last CAS deassertion to RAS assertion
CAS deassertion pulse width
Column address valid to CAS assertion
1.
2.
3.
4.
5.
6.
7.
Table 2-10 DRAM Page Mode Timings, Two Wait States
• BRW[1:0] = 00
• BRW[1:0] = 01
• BRW[1:0] = 10
• BRW[1:0] = 11
The number of wait states for Page mode access is specified in the DCR.
The refresh period is specified in the DCR.
The asynchronous delays specified in the expressions are valid for DSP56364.
All the timings are calculated for the worst case. Some of the timings are better for specific cases (e.g., t
equals 3
BRW[1:0] (DRAM Control Register bits) defines the number of wait states that should be inserted in each
DRAM out-of-page access.
RD deassertion will always occur after CAS deassertion; therefore, the restricted timing is t
There are no DRAMs fast enough to fit to two wait states Page mode @ 100MHz (See Figure 2-11)
Characteristics
Table 2-11 DRAM Page Mode Timings, Three Wait States
T
Characteristics
C
for read-after-read or write-after-write sequences).
Freescale Semiconductor, Inc.
For More Information On This Product,
DSP56364 Advance Information
Symbol
Go to: www.freescale.com
5
Expression
Symbol
t
RHCP
t
t
t
t
t
t
t
CAC
t
RSH
CAS
CRP
t
ASC
OFF
PC
AA
CP
2.25
3.75
4.75
6.75
2.5
4.5
1.5
Expression
2
2
3
1.25
Min
T
2
C
66 MHz
T
T
T
T
T
T
1, 2, 3, 7
C
C
T
T
T
T
C
C
C
C
T
C
C
C
C
4.0
C
T
7.0
4.0
Max
7.0
C
4.0
4.0
4.0
6.0
6.0
6.0
6.0
(continued)
1, 2, 3
Min
40.0
35.0
21.0
41.0
16.0
41.5
61.5
11.0
Min
0.0
6.0
—
—
—
—
80 MHz
OFF
MOTOROLA
Max
Max
13.0
23.0
—
—
—
—
—
—
—
—
—
—
—
—
and not t
Unit
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
PC
GZ.