Atmel SpW-10X user manual SpaceWire Router, User Manual, Preliminary

SpW-10X	Ref.:	UoD_SpW-10X_
SpaceWire Router		UserManual
	Issue:	3.4
User Manual
	Date:	11th July 2008

		1		4
		2	R1	5
4	4
		3		6
5	4

(a)

14

2 R2 5

36

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.

14

4 4 2 R1 5

36

(b)

14

2 R2 5

36

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.

14

4 4 2 R1 5

36

(c)

14

2 R2 5

36

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.

1		4	1		4
2	R1	5	2	R2	5
3		6	3		6
			(d)

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.

Preliminary 99