Atmel SpW-10X Manuel D’Utilisation

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Ref.:   UoD_SpW-10X_ 
UserManual
 
Issue:  3.4 
  
 
 
SpW-10X 
SpaceWire Router 
User Manual 
Date:  11
th
 July 2008 
 
 
Preliminary 
80
 
8.1.4 Link-Disable 
The SpaceWire port can be disabled therefore rendering the link unusable.  When a SpaceWire link 
which is running is disabled it will disconnect from the far end and refuse connection attempts by the 
far end of the link. Caution should be used when using this command for a stand alone router as 
disabling all the links will leave the router unusable, except through a reset operation. 
 
WARNING 
 If the link that is being used to configure the router is disabled then it will not be possible to configure 
the router, unless there is another not disabled connection that can be used. 
8.1.5  Automatic deactivate driver mode 
The SpaceWire port deactivate bit can be set to cause the data and strobe outputs for the link to be 
deactivated when the port is inactive.  The deactivate mode takes effect dependent on the state of the 
Auto-start and the Link-Disabled control bits in the  SpaceWire port control register (see section 9.4.3) 
and on the Enable Start on Request bit in the router control register (see section 9.5.3). 
When Auto-start is enabled and the deactivate bit is set then the data and strobe LVDS drivers are 
deactivated until the interface receives a connection attempt by an external SpaceWire device.  The 
drivers are then enabled until the external device disconnects the link or the SpaceWire link control bit 
setup is changed. 
When Start on Request is enabled and the deactivate bit is set the LVDS drivers are deactivated until 
a request is made from within the router to send data out of the SpaceWire port with deactivated 
output drivers i.e. a packet arriving at another port is addressed to be routed out of the SpaceWire port 
with deactivated outputs.  The drivers are enabled and the SpaceWire port will attempt to make a 
connection with the other end of the SpaceWire link. 
When Link-disable is asserted and the deactivate bit is set then the data and strobe LVDS drivers are 
always deactivated as the link is not in use.   
The figure below shows the effect of the deactivate bit when the link setting is Auto-start only.