Atmel SpaceWire Router SpW-10X Manual De Usuario

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Ref.:   UoD_SpW-10X_ 
UserManual
 
Issue:  3.4 
  
 
 
SpW-10X 
SpaceWire Router 
User Manual 
Date:  11
th
 July 2008 
 
 
Preliminary 
44
 
up. 
 
‘1’ => Timeout period is ~ 60-80 us. 
‘0’ => Timeout period is ~ 1.3 ms. 
 
Timeout Period is: 
‘1’ => 200x(2^2)x(10 MHz clk period) 
‘0’ => 200x(2^16)x(10 MHz clk period) 
An external pull down resistor (e.g. 4k7 
Ω) is 
recommended on this pin to provide the 
longer timeout interval. 
STAT_MUX_OUT(6) 
[maps to -> 
POR_START_ON_REQ_N] 
In 
Power on reset signal which determines if the 
output ports automatically start up when they 
are the destination address of a packet. 
When asserted (low) the output port will 
automatically start on request. 
This signal is active low. 
CMOS3V3 
STAT_MUX_OUT(7) 
[maps to -> 
POR_DSBLE_ON_SILENCE_N] 
In 
Power on reset signal which determines if the 
output ports are disabled when no activity is 
detected on an output port for the current 
timeout period. 
When asserted (low) an output port is 
disabled when it has not sent any information 
for longer than the current timeout period. 
This signal is active low. 
CMOS3V3 
 
WARNING 
In most onboard applications it is recommended to have Stat_mux_out(4) pulled low by default in 
order to enable the watchdog timers on reset. 
 
WARNING 
When the watchdog timers are not enabled the SpaceWire and external ports can block indefinitely if, 
for example, a source stops sending data in the middle of a packet. If watchdog timers are not enabled 
then it must be possible for a network manager to detect blocking situations and to reset the router or 
node creating the problem.