Spw-10x spacewire router – Atmel SpaceWire Router SpW-10X User Manual
Page 134
Ref.: UoD_SpW-10X_
UserManual
Issue: 3.4
SpW-10X
SpaceWire Router
User Manual
Date: 11
th
July 2008
Preliminary
134
SpaceWire port to SpaceWire port
Last bit of data into receiver to last bit of data out of transmitter (Worst case where transmitter is
sending a time-code and FCT character before data)
(
) (
) (
)
TXPERIOD
SYSPERIOD
RXPERIOD
SSDATA
T
T
T
T
Ч
+
Ч
+
Ч
=
23
8
5
SpaceWire port to External port
Last bit of data into receiver to external port not empty flag
(
) (
)
SYSPERIOD
RXPERIOD
SEDATA
T
T
T
Ч
+
Ч
=
8
5
External port to SpaceWire port
External port write enable to last bit of data out of transmitter (Worst case where transmitter is sending
a time-code and FCT character before data)
(
) (
)
TXPERIOD
SYSPERIOD
ESDATA
T
T
T
Ч
+
Ч
=
23
4
External port to External port
External port write enable to external port not empty flag.
(
)
SYSPERIOD
EEDATA
T
T
×
= 5
10.6.4 Time-code Latency
The maximum time taken to propagate a time code through a routing switch
SpaceWire port to SpaceWire port
Last bit of time-code into receiver to last bit of time-code out of transmitter (worst case where
transmitter has started sending a before time-code data character)
(
) (
) (
)
TXPERIOD
SYSPERIOD
RXPERIOD
SSTC
T
T
T
T
Ч
+
Ч
+
Ч
=
16
6
5
SpaceWire port to External port
Last bit of time-code into receiver to external port EXT_TICK_OUT rising edge
(
) (
)
SYSPERIOD
RXPERIOD
SETC
T
T
T
Ч
+
Ч
=
8
5
External port to SpaceWire port
EXT_TICK_IN rising edge to last bit of time-code out of transmitter (worst case where transmitter has
started sending a before time-code data character)
(
) (
)
TXPERIOD
SYSPERIOD
ESTC
T
T
T
Ч
+
Ч
=
16
6