Design And Implementation Of High Speed Image Acquisition Module Based On PXI Bus

With the rapid development of infrared detection technology,the image acquisition system makes higher design requirements for large-capacity data storage,data throughput and reliability interconnection.In order to realize the functional test of the infrared detector,this paper designs a high-capacity data acquisition and control module,which mainly discusses the designs of data high-speed storage,universal interface interconnection and FPGA reliability.To achieve reliable and high-speed storage of large-capacity data,NAND Flash high-speed and high-capacity storage architecture based on FPGA is designed in this paper.Firstly,the pipeline storage structure based on 4-logical unit NAND Flash is designed by independent operation of NAND Flash logical unit characteristic.Then,through the parallel flow mechanism,a data transfer channel between Camera Link,PXI interface and Flash is designed to achieve multi-chip Flashes parallel control.Finally,a Flash bad block management scheme is proposed to improve the addressing efficiency.In order to realize the common interconnection of the acquisition module and the computer,and solve the unreal-time,instability and complexity control problem that the high-speed image acquisition control card meets under TSOS(Time-sharing Operating System),a PXI bus highspeed data acquisition and control interface is designed based on RTOS(Real-time Operating System)VxWorks.PXI local bus is designed base on PCI9054.Combined with VxWorks PXI device driver features,a portable software control interface is developed on Vx Works.Through the DMA control,data transmission between the module and computer could be in high-speed and reliable.Aiming at the situation of the metastability in tests,FPGA feasible design is proposed from clock design and phase control,double latch design,reset processing and description language style state machine respectively,which makes the module work steady.Via the Vx Works test platform,the indicators and functions were verified,the module can achieve 50MHz/16 Bit infrared image data continuous access.And through PXI bus,data read speed reaches 33MB/s.After a large number of repeated tests,the module has been proved working reliable and stable.