With the development of computer technology and microelectronics technology, since the middle and late 1970s, testing instruments and meters have gradually combined with computers to transmit test data to computers for storage and processing through the corresponding interface bus. The technology developed to the 1990s, when high-performance data acquisition AD chips appeared, the precision, speed, resolution and other parameters of data acquisition were greatly improved. And the data transmission bus is gradually mature and applied with the progress of computer and communication technology. Typical data acquisition communication modes include VXI bus, PCI bus, PXI bus, RS serial port communication, TCP network communication, and high-speed PXIE data bus (PXI Express) 。 The most significant improvement and advantage of PXI Express over PXI is that it integrates the characteristics of PCI Express, adopts serial transmission and point-to-point bus topology. Unlike PXI, which shares bandwidth among all bus devices, PXI Express provides a separate transmission channel for each device.

PXIE is based on Compact PCI standard, adding clock and synchronous trigger bus, but its core is still PCI bus. PXI Express provides a separate transmission channel for each device. At the same time, its added clock, synchronous trigger signal and special interface physical characteristics make it have greater technical advantages in measurement, communication, industrial automation and other fields.

Data acquisition demand and development trend:

With the increasing number of test points for test research and development, the types of test signals are becoming richer, and the requirements for sampling rate are becoming higher and higher, the requirements of R&D personnel on acquisition equipment are also rising, such as:

➢ The equipment supports different types of sensors, and one set of equipment can complete different experiments/sudden tests/on-site troubleshooting and other work;  

➢ High sampling rate/high resolution, which is used to accurately capture dynamic signals in the test process;  

➢ High synchronization accuracy between channels and no difference in signals to ensure the synchronization and time consistency of data at different measuring points;  

➢ The transmission rate and storage rate of the chassis data bus are high, which can form a large channel test platform; In order to meet the development trends of new large-scale test platforms, data centers, functional secondary development, customized test reports, etc.:

➢ Multiple ways of synchronization can be realized between different chassis, and large test systems can be built, and devices can be synchronized;

➢ The data interaction and software handshake are flexible, and the experimental data can be sent and summarized to the upper computer or data processing center;  

➢ The device is intelligent/open, which is convenient for R&D personnel to carry out secondary development and customization of functions.  

Faced with the above requirements, the PXIE bus structure is more suitable for the architecture of large channel chassis. On the premise of ensuring large channels, high-speed data transmission and storage are maximized, and the clock synchronization of all channels on the PXIE bus is guaranteed. The third generation of DEWE3 series chassis of DEWETRON is equipped with high-speed TRION3 series boards, which can meet the above requirements for equipment. Next we will elaborate in the next article DEWETRON How to realize the above requirements based on PXIe bus, and describe the advantages of DEWETRON in combination with practical applications and cases.

DEWETRON's host box and test board based on PXI/E architecture can meet customers' high-speed acquisition of almost all physical signals/digital signals/bus signals. The combination of open hardware and software, as well as multiple data transmission modes and remote transmission control functions can meet customers' different functional requirements for data center, project achievements, project development, function customization, experimental reports, etc.  

The multi-functional/high-speed/open/test system of Dewicron will bring you the following convenient functions and capability improvements:

➢ High speed acquisition and storage of vibration, strain, temperature, pressure, voltage, current, charge, resistance and other signals;

➢ High signal acquisition accuracy and stable operation;  

➢ Modular design to adapt to different test requirements;

➢ Universal board, one card for multiple purposes, supports different physical quantities and sensors;

➢ Acquisition and analysis software with complete functions, suitable for various data acquisition and analysis needs;

➢ High speed storage of collected data;

➢ Equipment cascade and large system construction;

➢ Fast and stable data transmission to ensure the construction of data center;

➢ Open hardware and software, supporting secondary development and function customization;  

➢ Test flow, experiment standardization, report formatting.