4Links Diagnostic SpaceWire Interface DSI-RG408, User Manual

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Diagnostic SpaceWire Interface
EtherSpaceLink family User Manual
17. 6 .14.
EtherSpaceLink_read_packet_extension_callback()
S ynops i s
void EtherSpaceLink_read_packet_extension_callback
( EtherSpaceLink DSI_unit,
void * callback_buffer,
int callback_buffer_length,
void (*callback) ( int length,
int complete,
int data_buffer_position
)
)
D esc ri pt i on
EtherSpaceLink_read_packet_extension_callback()
r
e
gi s
te
r s a
bu
ff
e
r a
n
d a ca
llb
ack
p r o c e d u r e t ha t m ay be ca lle d , i f en a ble d , wh en a cha r ac te r f r om t h e exten d e d cha r ac te r s et i s r e c e i ve d
i
n t
h
e m
i dd
le o
f r
e
c
e
p
t
i
on o
f a
no
r
m
a
l
da
t
a pack
et.
Th i s p
e
r
m
i
t
s
t
h
e
asy
n
ch r
onou
s ha
n
d
l
i
n
g
o
f
exten d e d cha r ac te r s w i t h out t h e nee d f o r a no r m a l da t a r e ad to acc e p t a n d p r o c e ss s u ch pack et s .
Wh
en
ca
lle
d ,
t
h
e
ca
llb
ack p r
o
c
e
d
u
r
e
i s pass
e
d
t
h r
ee
pa r a
mete
r s:
length
i
n
d i ca
te
s
t
h
e numbe
r
o
f
b
y
te
s
o
f sp
e
c i a
l
da
t
a ac
tu
a
ll
y i
n t
h
e
ca
llb
ack
bu
ff
e
r
.
complete
i n d i ca te s wh et h e r t h e pack et i n t h e ca llb ack bu ff e r i s c om p lete ( 1 ) o r not (0). Th e
pack
et
w i
ll be
i
n
c
om
p
lete onl
y i f i
t
i s
l
a rg
e
r
t
ha
n t
h
e
ca
llb
ack
bu
ff
e
r, i
n
wh i ch cas
e
r
etu
r
n
i
n
g f r
om
t h e ca llb ack p r o c e d u r e w i ll r e s ult i n t ha t p r o c e d u r e be i n g ca lle d a g a i n w i t h t h e next s e g ment , o r
t
h
e
r
e
s
t o
f ,
t
h
e
sp
e
c i a
l
pack
et.
data_buffer_position
i n d i ca te s t h e i n d ex o f t h e next da t a b y te t ha t w i ll be w ri tten to t h e
no
r
m
a
l
da
t
a
bu
ff
e
r a
n
d
t
h
u
s s
e
r
ve
s
to
i
n
d i ca
te t
h
e
r
el
a
t
i
ve
p
o
s i
t
i
on o
f
t
h i s sp
e
c i a
l
pack
et.
F
o
r
ex a m p le , t i me - t a g s m ay o cc u r be f o r e t h e f ir s t b y te o f a da t a pack et ( da t a_ bu ff e r _p o s i t i on == 0) ,
be
f
o
r
e e
ach
ot
h
e
r da
t
a
b
y
te (
da
t
a_
bu
ff
e
r _p
o
s i
t
i
on > 0)
a
n
d
be
f
o
r
e t
h
e en
d
o
f pack
et m
a r k
e
r
( i .e. af te r t h e l as t da t a b y te , da t a_ bu ff e r _p o s i t i on == N wh e r e t h e r e a r e N da t a b y te s a t p o s i t i on s 0
to
N-1
).
I nput p ara mete r s
DSI_unit
t
h
e
ha
n
d
le
r
etu
r
ne
d
b
y a s
u
cc
e
ssf
ul
EtherSpaceLink_open()
c
omm
a
n
d
.
callback_buffer
a
bu
ff
e
r
to
c
ont
a i
n
r
e
c
e
i
ve
d sp
e
c i a
l
da
t
a
.
callback_buffer_length
t
h
e
s i z
e o
f
t
h
e
r
e
c
e
i
ve bu
ff
e
r
.
callback
a p r o c e d u r e to ca ll.
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