Corp. SpaceWire Router User Manual

Ref.:
UoD_SpW-10X_
UserManual
Issue:
3.4
SpW-10X
SpaceWire Router
User Manual
Date:
11
th
July 2008
Preliminary
52
7. SPACEWIRE ROUTER PACKET TYPES
This section describes how the routing control logic interprets packets.
7.1 PACKET ADDRESSES
The routing control logic interprets the first byte of each received packet as the packet address. The
packet address defines the physical ports through which the routing control logic will use to route the
packet towards its destination.
Packets which have a path address (0-31) as the first byte are always routed to the corresponding
physical port number on the router. Packets which have a logical address (32-255) are routed to
physical ports dependent on the contents of the routing table. The internal SpaceWire router routing
table can be set up to assign logical addresses to the physical ports, except the configuration port
(port 0) which can only be accessed by path addressing
The physical port addresses for the SpaceWire router and the expected packet type is defined in the
table below. The packet types can be viewed in section 0.
Table 7-1 Packet Address Mapping
Packet Address Expected Packet Type Physical Port type
0 Command packet Configuration port
1 Any type SpaceWire link port 1
2 Any type SpaceWire link port 2
3 Any type SpaceWire link port 3
4 Any type SpaceWire link port 4
5 Any type SpaceWire link port 5
6 Any type SpaceWire link port 6
7 Any type SpaceWire link port 7
8 Any type SpaceWire link port 8
9 Any type External FIFO port 1
10 Any type External FIFO port 2
11-31 N/A Invalid addresses
32-255 Any type Logical addresses
Note that logical address 255 is reserved in the SpaceWire standard [AD1].