Spw-10x spacewire router – Atmel SpaceWire Router SpW-10X User Manual
Page 83
Ref.: UoD_SpW-10X_
UserManual
Issue: 3.4
SpW-10X
SpaceWire Router
User Manual
Date: 11
th
July 2008
Preliminary
83
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1
10
2
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100
10
1
⎟
⎟
⎟
⎟
⎠
⎞
⎜
⎜
⎜
⎜
⎝
⎛
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MbitDIV
TX
FEEDBDIV
MHz
MHz
MbitRate
TXDIV
To provide a SpaceWire signal with a nominal 50/50 duty cycle, TXRATE and TX10MbitDIV should be
even integers.
Not all values of FEEDBDIV, TXDIV and TXRATE give valid clock signals. Table 8-1shows the
recommended values to use to achieve a range of SpaceWire transmit data rates.
Table 8-1 Setting SpaceWire Transmit Data Rate
TXRATE
Initialisation
Data Rate
0
1
2
3
4
5
6
7
8
9
10
FEEDB
D
IV
TXDIV
TX1
0
M
B
ITDIV
[1:1]
[1:3] [1:1] [3:5] [1:1] [5:7] [1:1] [7:9] [1:1] [9:11] [1:1]
Data
Rate
Duty
Cycle
5
0
19
200.0 100.0 66.67 50.0 40.0 33.33 28.57 25.0 22.22 20.0 18.18 10.000 [19:21]
4
0
17
180.0
90.0 60.0 45.0 36.0 30.0 25.71 22.5
20.0
18.0 16.36 10.000 [17:19]
3
0
15
160.0
80.0 53.33 40.0 32.0 26.67 22.86 20.0 17.78 16.0 14.55 10.000 [15:17]
2
0
13
140.0
70.0 46.67 35.0 28.0 23.33 20.0
17.5 15.56 14.0 12.73 10.000 [13:15]
1
0
11
120.0
60.0 40.0 30.0 24.0 20.0 17.14 15.0 13.33 12.0 10.91 10.000 [11:13]
0
0
9
100.0
50.0 33.33 25.0 20.0 16.67 14.29 12.5 11.11 10.0 9.09 10.000 [9:11]
5
1
9
100.0
50.0 33.33 25.0 20.0 16.67 14.29 12.5 11.11 10.0 9.09 10.000 [9:11]
4
1
8
90.0
45.0 30.0 22.5 18.0 15.0 12.86 11.25 10.0
9.0
8.18 10.000 [1:1]
3
1
7
80.0
40.0 26.67 20.0 16.0 13.33 11.43 10.0
8.89
8.0
7.27 10.000 [7:9]
2
1
6
70.0
35.0 23.33 17.5 14.0 11.67 10.0
8.75
7.78
7.0
6.36 10.000 [1:1]
1
1
5
60.0
30.0 20.0 15.0 12.0 10.0
8.57
7.5
6.67
6.0
5.45 10.000 [5:7]
0
1
4
50.0
25.0 16.67 12.5 10.0 8.33
7.14
6.25
5.56
5.0
4.55 10.000 [1:1]
5
2
4
50.0
25.0 16.67 12.5 10.0 8.33
7.14
6.25
5.56
5.0
4.55 10.000 [1:1]
4
2
4
45.0
22.5 15.0 11.25 9.0
7.5
6.43
5.63
5.0
4.5
4.09 9.000
[1:1]
3
2
3
40.0
20.0 13.33 10.0
8.0 6.67
5.71
5.0
4.44
4.0
3.64 10.000 [3:5]
2
2
2
35.0
17.5 11.67 8.75
7.0 5.83
5.0
4.38
3.89
3.5
3.18 11.667 [1:1]
1
2
2
30.0
15.0 10.0
7.5
6.0
5.0
4.29
3.75
3.33
3.0
2.73 10.000 [1:1]
0
2
2
25.0
12.5 8.33 6.25
5.0 4.17
3.57
3.13
2.78
2.5
2.27 8.333
[1:1]
In Table 8-1 the values with a white background are the values that should be used. The ones in
red/shaded should not be used.
The first three columns give settings for the FEEDBDIV pins on the SpW-10X device, the TXDIV field
in the transmit clock register (see section 9.5.9) and the TX10MbitDIV field also in the transmit clock
register.