4Links EtherSpaceLink Series, User Manual

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EtherSpaceLink-RG408
EtherSpaceLink family User Manual
9. Opt i on TT - T i me T ag s
A n i nte r n a l q u a r t z c r y st a l c o nt r oll ed o s c i ll a t o r f eeds a c ou nte r t ha t r e p r esents t h e t i me , t o a r es olu t i o n
o f l
ess t
ha
n 1 0 ns ,
f
r
o
m
w h
en t
h
e
TC P/
I
P
i nte r
fac
e
w a
s
l a
st
c o
nne
c
ted.
Tha
t t i me
ca
n be
ca p
t
u
r ed
a
nd
r e po r ted t o t h e u se r e ach t i me a n en a b l ed e v ent o cc u r s. Th i s op t i o n a llow s t i me ca p t u r e o n t h e r e c e i p t
o f o
ne
o
r m
o
r e
o f
t
h
ese e v ents:
t h e f ir st b y te o f a p ac k et;
i nte r med i
a
te b y tes o
f
p
ac
k ets;
t
h
e end
- o f- p ac k
et m
a
r
k
e r,
E O P
;
t h e e rr o r - end - o f- p ac k et m a r k e r, EEP ;
U se r s s h oul d n o te t ha t a t i me - t a g r e po r t i s ten b y tes lo n g, a nd i f i t i s en a b l ed o n e v e r y b y te o f a p ac k et ,
t
h
i s r es
ul
ts i n e
l
e v en t i mes
a
s m
u ch
t r
aff
i
c a
s
f o
r t
h
e
p ac k
et
a lo
ne.
Th
i s
ca
n s
oo
n s
a
t
u
r
a
te t
h
e
E
t
h
e r net
c o nne c t i o n a nd s h oul d be u sed w i t h ca u t i o n. T i me - t a ggi n g t h e f ir st d a t a b y te a nd t h e end o f p ac k et
m
a
r
k
e r giv es
u
se
f ul
i n
f o
r m
a
t i
o
n
w
i t
h a
m
u ch low
e r
o
v e r
h
e
a
d
a
nd i s r e
c o
mmended
f o
r n
o
r m
a l u
se.
O p
t i
o
n
TT fac
i
l
i t i es m
a y
be
acc
essed:
In t h e “ T i me - t a g s ” pull - d ow n men u i n t h e
SpaceWireUI
p r o gr a m;
U
s i n g t
h
e
/w
c o
mm
a
nd
- l
i ne
p a
r
a
mete r i n t
h
e
SpWIO
p
r
o
gr
a
m;
a
nd
U s i n g t h e
EtherSpaceLink_TT_enable_reporting()
a nd
EtherSpaceLink_extract_timetag()
f
u n
c
t i o ns i n t
h
e
C-
l
a
n g u
a
g e
A
ppl i
ca
t i o n
P r o gr a mm i n g Inte r fac e ( C-A P I ) .
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www.4Links.co.uk
support@4Links.co.uk
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