Embedded Software Solution
Full support for the new and unique graphical embedded system design approach, using
LabVIEW Embedded was a key requirement for NAXYS. It helped the system engineers to
focus on their application functions rather than on details like device drivers and system
Figure 3: Graphical Embedded System Programming using LabVIEW Embedded. Click here for larger image.
The above figure shows an example how the system's buffered ADC acquisition was
implemented using LabVIEW Embedded. After setting up the Hardware platform, ADC, FIFO and
Serial Ports, two parallel tasks are initiated. The upper task (Timed Loop in LabVIEW, a Thread
in VDK's operating system) is "fired" as soon as an ADC buffer has been processed and the analog values are copied to a LabVIEW data structure such as an array.
This data is then fed into a real time FIFO and passed to another loop for further signal processing or data management, like writing to a compact flash card or sending to a terminal.
Key application software functions include:
Main application tasks implemented by Timed Loops / VDK-Threads;
Software modularity and re-usability using submodules/sub-VI's;
Inter-task data communication by real time FIFO's and global data structures;
Application logic based on a classic state machine;
An embedded file handler for up to 4GB removable media (CF-Card);
Four-channel serial interfaces for acoustic modems and water sensors;
Intelligent power and battery management;
Shutdown, Wakeup and Watchdog logic;
Triaxis accelerometer sensor interface;
Measuring of water current, salinity, pressure and temperature;
LabVIEW Embedded Module for ADI Blackfin Library.
One of Schmid Engineering's part was the development of all necessary board functions, device driver VI's and additional operating system services to realize reliable, deterministic real time behaviour on the basis of the LabVIEW Embedded Module for ADI Blackfin.
The library functions include : Board initialisation, shut down and wake up, RTC programming, power management, watchdog, ADC, DIO, Serial IO, Removable Media (CF), GPIO, Timer and Flash programming.
Schmid Engineerings firmware engineers tweaked the embedded operating system VDK to help realising synchronized data sampling of all CSP's, in fact the system's core function :
All CSP's start triggered sampling
with an accuracy of maximum 100us
Each MSP's and CSP's clock stability
is less then 1ms/30min.
The acoustic modems propagation
delays and any software latencies are
This project served as a real life test bench for Schmid Engineering's latest product "Zbrain
BSP for LabVIEW". Thanks to the valuable ideas, suggestions and test feedback from NAXYS
AS, the Board Support Package (BSP) continuously matured in the shortest of times.
Embedded system engineers now can gain from serious, productive graphical embedded
Embedded Hardware Solution
Both MSP and CSP hardware rely on the Embedded Zbrain System Toolbox supplied by Schmid
Engineering AG, a swiss solution provider for embedded systems. This modular solution is
based on Analog Devices' Blackfin processor by and programmed using National
Instruments "LabVIEW Embedded Module for ADI Blackfin". The low power, mixed signal board
ZMobile serves as the main platform for the pipeline monitoring system.
This off-the-shelf solution provided all required hardware functions for DeepBlue:
High Computing DSP Power
Dynamic Energy Management
Smart Battery functions
Onboard RTC and Watchdog
Analog IO for triaxis accelerometer
Digital IO for trigger impulse
Serial IO (acoustic modems)
Removable Media (data storage)
Figure 4: ZMobile add-on board.
The final element is an Expansion Board Connector for a
custom specific IO and Controller
Board. Most of the functionality was already provided
by Zmobile. A custom specific add-on board completed all
missing circuits, connectors and interfaces. This two board approach and combination of
standard and customer solution saved precious
engineering time and lowered project risks.