Atmel SpaceWire Router SpW-10X Manual De Usuario

Ref.:   UoD_SpW-10X_ 

 

Issue:  3.4 

  

 

Date:  11

 

 

85

 

8.2.1  Start on request mode 

The Start on Request mode is enabled by setting the CFG_START_ON_REQ bit in the router control 
register.  The input signal POR_START_ON_REQ_N determines the power on or reset state of the 

 bit. 

When a SpaceWire packet is received which is to be routed out of a SpaceWire port that is not 
running it would normally be discarded. If the Start on Request mode is enabled instead of discarding 
the packet the SpaceWire port will attempt to make a connection with the other end of the link. If a 
connection can be made then the packet is forwarded on towards its destination. This is illustrated in 
Figure 8-4. This mode allows the SpaceWire ports to be started automatically when there is data to 
send. This can be used together with output deactivate to save power. 

R1

R2

1

2

1

2

Auto-Start default mode

and Start on Request

enabled in both routers

R1

R2

1

2

1

2

2

Packet with 

address 2

R1

R2

1

2

1

2

Connection Attempt

2

Link Started and 

Data Transfer

1

2

3

2

 

8.2.2 Disable on Silence mode 

The Disable on Silence mode is enabled by setting the CFG_DISABLE_ON_SILENCE bit in the router 
control register.  The input signal POR_DISABLE_ON_SILENCE_N determines the power on or reset 
state of the CFG_DISABLE_ON_SILENCE bit. 

Figure 8-5 illustrates operation in the Disable on Silence mode.