Atmel SpaceWire Router SpW-10X - Manual (Page 99)

Ref.: UoD_SpW-10X_
UserManual
Issue: 3.4
SpW-10X
SpaceWire Router
User Manual Date: 11 th
July 2008
Preliminary
99
R1
1
2
3
4
5
6
(a)
4 5
R2
1 4
2
3
5
6
4 4
Figure 8-21 Source Node Stalled (a)
b) The packet from routing switch R1 port 3 is routed towards its destination but during packet
transfer the source node stalls and does not supply any further data or the end of packet.
R1
1
2
3
4
5
6
(b)
R2
1 4
2
3
5
6
4 4
Figure 8-22 Source Node Stalled (b)
c) The packet is blocked and the packet waiting at routing switch R1 port 2 cannot be routed.
R1
1
2
3
4
5
6
(c)
R2
1 4
2
3
5
6
4 4
Figure 8-23 Source Node Stalled (c)
d) After an undetermined time the source node supplies the remaining data and end of packet
and the packet waiting at R1-2 can be routed.
R1
1
2
3
4
5
6
(d)
R2
1 4
2
3
5
6
Figure 8-24 Source Node Stalled (d)
Watchdog Timer Mode
What happens when a source stalls and Watchdog Timer mode is being used is illustrated in Figure
8-25 to Figure 8-28:
a) A packet arrives at routing switch port 3 with destination address 4, 5 which will route to
routing switch R2 port 5. Another packet arrives which is destined for routing switch R2 port 4.