Flags – Analog Devices ADSP-21020 User Manual
Page 15
ADSP-21020
REV. C
–15–
Flags
K/B/T Grade K/B/T Grade B/T Grade
K Grade
20 MHz
25 MHz
30 MHz
33.3 MHz
Frequency Dependency*
Parameter
Min
Max
Min
Max Min Max
Min Max
Min
Max
Unit
Timing Requirement:
1
t
SFI
FLAG3-0
IN
Setup before CLKIN High
19
16
14
13
19 + 5DT/16
ns
t
HFI
FLAG3-0
IN
Hold after CLKIN High
0
0
0
0
ns
t
DWRFI
FLAG3-0
IN
Delay from xRD, xWR Low
12
8
5
3
12 + 7DT/16 ns
t
HFIWR
FLAG3-0
IN
Hold after xRD, xWR
0
0
0
0
ns
Deasserted
Switching Characteristic:
t
DFO
FLAG3-0
OUT
Delay from CLKIN High
24
24
24
24
ns
t
HFO
FLAG3-0
OUT
Hold after CLKIN High
5
5
5
5
ns
t
DFOE
CLKIN High to FLAG3-0
OUT
Enable
1
1
1
1
ns
t
DFOD
CLKIN High to FLAG3-0
OUT
Disable
24
24
24
24
ns
NOTES
*DT = t
CK
– 50 ns
1
Flag inputs meeting these setup and hold times will affect conditional operations in the next instruction cycle. See the Hardware Configuration chapter of the
ADSP-21020 User’s Manual for additional flag servicing information.
x = PM or DM.
CLKIN
t
DFOE
FLAG3-0
OUT
t
DFO
t
HFO
t
DFO
t
DFOD
FLAG OUTPUT
CLKIN
t
HFI
FLAG3-0
IN
FLAG INPUT
t
SFI
t
DWRFI
t
HFIWR
xRD, xWR
Figure 7. Flags