adsp-21160m Analog Devices, Inc., adsp-21160m Datasheet - Page 34

• Manufacturer Part Number: adsp-21160m
• Description: Sharc Dsp Microcomputer
• Manufacturer: Analog Devices, Inc.

ADSP-21160M
Link Ports
Calculation of link receiver data setup and hold relative to
link clock is required to determine the maximum allowable
skew that can be introduced in the transmission path
between LDATA and LCLK. Setup skew is the maximum
delay that can be introduced in LDATA relative to LCLK
(setup skew = t
maximum delay that can be introduced in LCLK relative to
LDATA (hold skew = t
lations made directly from speed specifications will result in
unrealistically small skew times because they include
multiple tester guardbands.
Note that there is a two-cycle effect latency between the link
port enable instruction and the DSP enabling the link port.
Maximum throughput varies across link port trans-
mit/receive pairs.
all transmit/receive pairs based on setup skew of 0.5 ns
(setup skew=t
results indicate 80 MHz operation across all link ports. All
hold time skews are equal to 0.5 ns or greater for all link
port transmit/receive pairs at 80 MHz. Based upon these
values, all link port transmit/receive pairs can be operated
at maximum throughput for LxCLK:CCLK ratios of 2:1,
3:1, and 4:1 at 80 MHz CCLK. To operate all link port
transmit/receive pairs at LxCLK:CCLK ratio of 1:1, the
core clock frequency must be no greater than 62.5 MHz.
Maximum data throughput values are based upon the reset
value of the LAR Link Port Assignment Register (Link
Buffer 0 assigned to Link Port 0, Link Buffer 1 assigned to
Link Port 1, etc.). Throughputs are not guaranteed for LAR
settings other than the reset LAR value. For additional
details on LAR, refer to the ADSP-21160 DSP Hardware
Reference manual.
Table 18. Link Port—Maximum Data Throughput for
Transmit/Receive Pairs
Transmit
Link Port
0
1
LCLKTWH
LCLKTWH
Receive
Link Port
0
1
2
3
4
5
0
1
2
3
4
5
Table 18
min–t
Min – t
LCLKTWL
shows maximum throughput for
DLDCH
DLDCH
Min – t
Maximum Operating
Frequency (MHz)
71.43
74.07
71.43
80
80
76.92
68.97
71.43
68.97
80
76.92
74.07
–t
– t
SLDCL
SLDCL
HLDCH
=0.5 ns). Hold skew
). Hold skew is the
– t
HLDCL
). Calcu-
–34–
Table 18. Link Port—Maximum Data Throughput for
Transmit/Receive Pairs (Continued)
Transmit
Link Port
2
3
4
5
Receive
Link Port
0
1
2
3
4
5
0
1
2
3
4
5
0
1
2
3
4
5
0
1
2
3
4
5
Maximum Operating
Frequency (MHz)
68.97
71.43
71.43
80
76.92
74.07
64.52
66.67
66.67
71.43
71.43
71.43
64.52
66.67
66.67
74.07
74.07
71.43
62.5
66.67
64.52
71.43
71.43
71.43
REV. 0