Compact, low-weight, and high-performance airborne acquisition and transmission systems
As part of this demonstration, we are going to show the AXN/ADC/401 operating in the Axon chassis simultaneously with the KAD/ADC/136 operating in the KAM-500 chassis. The two of them will be programmed in the one software, DAS Studio, and daisy-chained together without the need for a switch to synchronize the two of them. The Axon BCU has two Ethernet ports, both Gigabit-capable, that can also act as a PTP V1/2 grandmaster. This offers the ability to connect the chassis in a daisy chain manner without the need for a switch to synchronize them.
We’re going to connect a cable to the BCU that has two Ethernet links. I’m going to connect the top block connector to the KAM BCU. So one of the cables from the Axon is going to go into port A of the KAM chassis and the other one is going to be connected to the PC.
In DAS Studio, we are going to create a task to sample to Axon ADC/401 and the KAD/ADC/136 at the same time. To do that I’m going to run ‘Discover’ and add an IP address range to discover across. The Axon is 192.168.28.1 and the KAD is 192.168.28.3. I’m adding those and removing the one we don’t need – 192.168.28.2 and click ‘run discover’.
When discover is complete, you can see down in the status information window that it found the Axon 16U chassis, the Axon BCU, Axon ADC, and the KAM chassis, BCU and ADC. I’m going to save that to a file, close down discovery and then open that file in DAS Studio.
You can see your Axon chassis, your Axon BCU, and ADC/401. Then the KAD chassis has the KAD BCU and ADC/136. Going back to the Axon ADC module, for this example I’m going to use differential-ended voltage. I’m leaving everything at FIR filtering and filter cutoff at ¼ of the sample rate. I’m going to use voltage excitation set at 0. I don’t need for this setup to define the linearization algorithm as I’m not using a thermocouple or RTD channel.
On the equivalent KAD module, I’m going to use the same settings to match up – using FIR filtering and cutting off at ¼ of the sample rate. I’m setting the voltage excitation at 0. The BCU on the Axon has a dual gigabit switch core and you can set it to be 100BASE-Tx or auto-negotiate – I’m leaving it at auto-negotiate. Block traffic from other ports and chassis are left unset.
Then I’m setting the Axon PTP proto to ‘PTPv2 delay request’ and act as a grandmaster. On the KAD/BCU again I'm setting it to ‘PTPv2 delay request’ but this time leaving it as a client. The Axon BCU will be the grandmaster of the system, no need for a switch.
At this point, we have programmed the two systems – the Axon and the KAD. We’re sampling the ADC/401 and 136 at 100Hz in separate packets. I’m going to input a 1Hz sine wave into both and show the 2 of them in GS Works and show the correlation between the two signals.
So here we have the ADC/401 and the ADC/136 at 1Hz overlaid on top of each other. If we stop and zoom in we can see they are extremely coherent.
This demonstration has shown that in DAS Studio the Axon and KAM-500 systems work seamlessly side by side, the Axon system synchronizing the KAM-500 without the need of a switch. It also shows that the Axon and KAM-500 samples are coherent with each other.