Pike
Technical
Manual
V5.2.3
38
FireWire
FireWire
IIDC V1.31 camera control standards
Along
with
IEEE1394b,
the
IIDC
V1.31
standard
arrived
in
January
2004,
evolving
the
industry
standards
for
digital
imaging
communications
to
include
I/O
and
RS232
handling,
and
adding
further
formats.
The
increased
bandwidths
enable
transmitting
high-resolution
images
to
the
PC’s
memory
at
high
frame
rates.
Compatibility between IEEE1394a and IEEE1394b
Compatibility example
It
is
possible
to
run
a
IEEE1394a
and
a
IEEE1394b
camera
on
the
1394b
bus.
You
can
e.g.
run
a
Pike
F-032B
and
a
Marlin
F-033B
on
the
same
bus:
•
Pike
F-032B
@
S800
and
120
fps
(5120
bytes
per
cycle,
64%
of
the
cycle
slot)
•
Marlin
F-033B
@
S400
and
30
fps
(1280
bytes,
32%
of
the
cycle
slot)
Bus
runs
at
800
Mbit/s
for
all
devices.
Data
from
Marlin’s
port
is
up-converted
from
400
Mbit/s
to
800
Mbit/s
by
data
doubling
(padding),
still
needing
32%
of
the
cycle
slot
time.
This
doubles
the
bandwidth
requirement
for
this
port,
as
if
the
camera
were
running
at
60
fps.
Total
consumption
is
thus
5120
+
2560
=
7680
bytes
per
cycle.
IEEE1394a
camera
connected
to
IEEE1394b
bus
The
cable
explains
dual
compatibility:
This
cable
serves
to
connect
an
IEEE1394a
camera
with
its
six-
pin
connector
to
a
bilingual
port
(a
port
which
can
talk
in
a-
or
b-language)
of
a
IEEE1394b
bus.
In
this
case,
the
b-bus
communicates
in
a-language
and
a-speed
with
the
camera
achieving
a-performance
IEEE1394b
camera
connected
to
IEEE1394a
bus
The
cable
explains
dual
compatibility:
In
this
case,
the
cable
connects
an
IEEE1394b
camera
with
its
nine-pin
connector
to
a
IEEE1394a
port.
In
this
case,
the
b-camera
communicates
in
a-language
with
the
camera
achieving
a-performance
Figure 4: IEEE1394a and IEEE1394b cameras and compatibility
1394b port
1394a camera
1394a port
1394b camera
