ADSP-21065 Analog Devices, ADSP-21065 Datasheet - Page 16

• Manufacturer Part Number: ADSP-21065
• Description: DSP Microcomputer
• Manufacturer: Analog Devices

ADSP-21065L
Memory Read—Bus Master
Use these specifications for asynchronous interfacing to memories (and memory-mapped peripherals) without reference to CLKIN.
These specifications apply when the ADSP-21065L is the bus master when accessing external memory space. These switching char-
acteristics also apply for bus master synchronous read/write timing (see Synchronous Read/Write—Bus Master below). If these tim-
ing requirements are met, the synchronous read/write timing can be ignored (and vice versa). An exception to this is the ACK pin
timing requirements as described in the note below.
Parameter
Timing Requirements:
t
t
t
t
t
t
Switching Characteristics:
t
t
t
t
t
W = (number of wait states specified in WAIT register) × t
HI = t
H = t
NOTES
1
2
3
Data Delay/Setup: User must meet t
The falling edge of MSx, SW, BMS, are referenced.
ACK is not sampled on external memory accesses that use the Internal wait state mode. For the first CLKIN cycle of a new external memory access, ACK must be
DAD
DRLD
HDA
HDRH
DAAK
DSAK
DRHA
DARL
RW
RWR
RDGL
valid by t
subsequent cycles of a wait stated external memory access, synchronous specifications t
(Both, after internal wait states have completed).
CK
CK
(if an address hold cycle occurs as specified in WAIT register; otherwise H = 0).
(if an address hold cycle or bus idle cycle occurs, as specified in WAIT register; otherwise HI = 0).
DAAK
ADDRESS
or t
MSx , SW
DMAG
DSAK
Address, Selects Delay to Data Valid
RD Low to Data Valid
Data Hold from Address Selects
Data Hold from RD High
ACK Delay from Address, Selects
ACK Delay from RD Low
Address, Selects Hold After RD High
Address, Selects to RD Low
RD Pulsewidth
RD High to WR, RD Low
RD High to DMAGx Low
DATA
BMS
ACK
WR
RD
or synchronous specification t
DAD
or to t
t
DARL
1
DRLD
3
t
3
DAAK
or synchronous specification t
SACKC
2
CK
3
for wait state modes External, Either, or Both (Both, if the internal wait state is zero). For the second and
.
2, 3
t
DSAK
t
1, 2
DAD
t
DRLD
SSDATI
t
RW
SACKC
.
and t
Min
0.0
0.0
–1.0 + H
3.0 + 6 DT
25.0 + 26 DT + W
4.5 + 6 DT + HI
11.0 +12 DT + HI
HACKC
must be met for wait state modes External, Either, or Both
t
Max
28.0 + 32 DT + W
24.0 + 26 DT + W
24.0 + 30 DT + W
19.5 + 24 DT + W
HDRH
t
HDA
t
DRHA
t
t
RWR
RDGL
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns