ADSP-2104_15 Datasheet, PDF (24/36 Pages) Analog Devices – Low Cost DSP Microcomputers

ADSP-2104/ADSP-2109
TIMING PARAMETERS (ADSP-2104/ADSP-2109)
MEMORY READ
Parameter
Timing Requirement:
t_RDD RD Low to Data Valid
t_AA
A0–A13, PMS, DMS, BMS to Data Valid
t_RDH Data Hold from RD High
Switching Characteristic:
t_RP
RD Pulse Width
t_CRD CLKOUT High to RD Low
t_ASR
A0–A13, PMS, DMS, BMS Setup before
RD Low
t_RDA A0–A13, PMS, DMS, BMS Hold after RD
Deasserted
t_RWR RD High to RD or WR Low
20 MHz
Min
Max
12
19.5
0
17
7.5
22.5
2.5
3.5
20
Parameter
Timing Requirement:
t_RDD RD Low to Data Valid
t_AA A0–A13, PMS, DMS, BMS to Data Valid
t_RDH Data Hold from RD High
Switching Characteristic:
t_RP RD Pulse Width
t_CRD CLKOUT High to RD Low
t_ASR A0–A13, PMS, DMS, BMS Setup before
RD Low
t_RDA A0–A13, PMS, DMS, BMS Hold after RD
Deasserted
t_RWR RD High to RD or WR Low
NOTE
w = wait states × t_CK.
CLKOUT
A0 – A13
DMS, PMS
BMS
RD
D
WR
Frequency Dependency
(CLKIN ≤ 20 MHz)
Min
Max
0
0.5t_CK – 8 + w
0.25t_CK – 5
0.25t_CK – 10
0.25t_CK – 9
0.5t_CK – 5
0.5t_CK – 13 + w
0.75t_CK – 18 + w
0.25t_CK + 10
t_ASR
t_RP
t_CRD
t_RDD
t_AA
t_RDA
t_RWR
t_RDH
Figure 22. Memory Read
–24–
Unit
ns
ns
ns
ns
ns
ns
ns
Unit
ns
ns
ns
ns
ns
ns
ns
REV. 0