Atmel SpW-10X Data Packets, Command Packets, Supported Commands, SpaceWire Router, User Manual

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

7.5 DATA PACKETS

Packets which have addresses in the range 1 to 255 are routed to the SpaceWire ports and the external ports dependent on the packet address. Data packets have an address header byte a cargo field and an end of packet marker. The normal packet structure is show below.

ADDRESS

1-255

CARGO

EOP/EEP

Figure 7-1 Normal router data packets

7.6 COMMAND PACKETS

Command packets are routed to the internal configuration port when the packet address is zero. Command packets perform write and read operations to registers in the SpaceWire router. Command packets accepted by the SpaceWire router are in the form shown in Figure 7-2.

Configuration read packets are in the form:

ADDRESS

0

COMMAND

EOP

Figure 7-2 Command Packet Format

The SpaceWire router supports the Remote Memory Access Protocol (RMAP) [AD2] for configuration of the internal router control registers and monitoring of the router status.

The following sections define the RMAP commands which are supported and the format of the RMAP commands used by the SpaceWire Router.

7.6.1 Supported Commands

The RMAP Command set is listed in Table 7-4 and the supported RMAP commands are defined. The commands which are not used are depicted with a grey background.

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