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

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

Addresses

80 – HIGH Priority

52 – LOW Priority

1 2

52	1
	2	5
	R1
52	3
	4

1

2

R1 5

52 3

80 4

	Two packets waiting to use port 5							Packet from port 1 is selected
	(Previous port which accessed port 5 = 4)							HIGH priority packet arrives at port 4
3						4
		52	1						52			1
			2		5							2	5
				R1								R1
		52	3									3
			4									4
	Packet from port 1 completes							Packet from port 4 completes
	HIGH priority packet from port 4 is selected						Previous low priotity packet which accessed port 5 = 1
		Port number 3 waits						Therefore port 3 is selected
		Packet arrives on port 1								Packet on port 1 waits
5						6
				1							1
				2	5						2		5
				R1								R1
				3							3
				4							4
		Packet from port 3 completes						Packet from port 1 completes
	Packet waiting on port 1 is selected

Figure 8-9 Arbitration of two packets with different priority (2)

Preliminary 91