ETTC'2003 - SEE

Driven by requirements to keep mission
critical military aircraft systems
operational despite of unusual external
conditions, CES is integrating into its
forthcoming generation of function units
an unprecedented number of monitoring
and re-configuration elements. It wouldn’t
come as a surprise if these elements, once
developed, would also prove useful in
commercial aircraft systems.
The function unit
Over the last eight years, the hardware
elements on which function units are based
were using successive generations of the
same basic elements:
• General-purpose PPC processors.
• Application specific FPGAs.
• Bus standards like VME and CPCI
for interconnecting SBCs.
Three examples • PCI for integrating I/O options and
/ or auxiliary CPU power (PMCs).
The following diagrams show elements of
three different systems, each built using
function units based on the same
hardware and firmware elements:
1. Shows a section of an
AIDASS test system:
one dualMIL 1553 and
one EFABUS function
unit are combined with
one simulation and one
link CPU.
2. one section of the
IENA-N2-AFDX
concentrator shows one
AFDX function unit (6
dual redundant AFDX
channels) together with
the controller unit,
which implements the
link and datation
function.
3. Two function units used
in the Predator drone
are shown: The LC unit
controls the
communication
between air and ground
while the DP unit is
used for video control
and image processing.
Note that this system
exists in ‘mirrored’
versions for air and
ground.
All these elements can be demonstrated by
looking at the architecture of the AFDX
function unit shown in the diagram
below:
The RIO3 8064, a VME SBC based on the
PPC 750 or PPC 7410 implements the user
interface and high level configuration and
statistic services. The real time critical
parts of the AFDX protocol are handled in
an application specific FPGA on the
MFCC 8443 PMC. This MFCC carries as
well a PPC 750CX processor, which
controls the FPGA and handles all aspects
of the protocol being able to tolerate the
latency
restrictions implied by software
implementation. Together with the
integrated firmware and software, the
function unit constitutes a bundled
package, ready to be integrated into a
larger system. As an example, the structure
of the AFDX 8854 software/firmware
levels is detailed below: