Complete Technical Guide for Euresys Coaxlink CXP Capture Card

Onboard image preprocessing includes: input LUT (monochrome camera), Bayer CFA decoding (multiple interpolation algorithms), flat field correction, and JPEG compression (Quad CXP-12 JPEG model only). Especially for the JPEG model, it has four independent JPEG encoders built-in, processing up to 250 MPixel/s per channel, and outputting JPEG and RGB preview streams with a typical 20 line delay, greatly reducing the CPU load of the host and suitable for multi-channel ultra high definition recording and monitoring applications.

I/O Toolbox and Trigger Synchronization

Coaxlink is equipped with a wide range of I/O interfaces (10 or 20 depending on the model), including high-speed differential inputs (compatible with RS-422/485, supporting 5MHz orthogonal encoders), 5V TTL bidirectional, isolated current type inputs (up to 30V, 50kHz, 2500V isolated), and isolated contact outputs (30V/100mA). All inputs have programmable digital filtering (debounce) and polarity reversal.

I/O Toolbox is a programmable event generator composed of multiple processing tools cascaded together:

LIN (Line Input): detects events generated by input edges.

QDC (Quadrature Decoder): decodes A/B signals, provides position values and motion directions, and has built-in reverse compensation.

DIV (Diver): Every N input events generate an output event.

MDV (Multiplier/Divider): Every D events generate M output events.

DEL (Delay): Delay the event by a programmable time or the number of encoder beats.

UAS (User Actions Scheduler): Execute user-defined actions (set/reset output pins) at predetermined times or encoder positions.

Through these tools, users can build complex triggering logic without writing FPGA code, such as using encoders to trigger circuit acquisition, using frequency division to achieve fixed interval sampling, or outputting strobe signals after delay.

C2C Link (Card to Card Link) is the core of multi card synchronization. Through the onboard 6-pin connector, multiple acquisition cards can be cascaded to achieve precise synchronization of trigger signals and exposure initiation. Within the same PC, the synchronization delay is less than 10ns; when crossing PCs (through InterPC adapters and RJ45 Ethernet cables), the delay is less than 265ns under a total length of 40 meters with 3 PCs, and can be expanded up to 32 PCs and 1200 meters. The maximum synchronization frequency is 2.5MHz (short distance) or 200kHz (long distance), which is very suitable for large-scale multi camera systems (such as multi view 3D detection).

Software Ecology and Debugging Tools

Coaxlink provides cross platform drivers that support Windows 7/8.1/10, Linux (x86/x86_64/aarch64), and macOS. The API hierarchy includes the EGrabber class (C++/. NET) and the GenICam GenTL Producer library, which are fully compatible with GenApi, SFNC, and GenTL standards and can seamlessly integrate with third-party visual software such as HALCON, Common Vision Blox, LabVIEW, etc.

Memento event logging tool is a powerful tool for development and debugging. It can record all events from cameras, capture cards, drivers to applications (including timestamps, contextual data, I/O status) and present them in timing diagrams and logic analyzer views. Whether it's troubleshooting trigger jitter, data loss, or performance bottlenecks, Memento provides visibility comparable to hardware logic analyzers, greatly reducing debugging cycles.

Direct GPU transfer supports AMD DirectGMA and NVIDIA CUDA, directly writing image data to video memory, bypassing CPU memory copying, reducing latency and CPU usage, suitable for deep learning and real-time processing scenarios.

For high-end users, Coaxlink Quad/Otto supports CustomizaLogic - allowing users to use Xilinx Vivado development tools to upload custom FPGA code to the acquisition card, occupying up to 70%~91% of FPGA resources to achieve customized image preprocessing or specialized algorithms without the need for additional hardware.

Selection Guide and Typical Applications

When selecting, comprehensive consideration should be given to the number of cameras, single channel bandwidth, whether compression or 3D processing is required, PCIE slot type, and heat dissipation conditions.

Single camera low speed (<1.25GB/s): Coaxlink Mono CXP-12 LH (passive cooling) or Duo (can connect dual cameras) have high cost-effectiveness.

Four camera high speed (total bandwidth up to 5GB/s): Coaxlink Quad CXP-12 (requires x8 slots) is the preferred choice; If the camera only supports CXP-6 (6.25Gbps), then Quad G3 (PCIe 3.0 x4, effective 3.35GB/s) is sufficient.

Ultra long distance (>40 meters): Coaxlink Quad CXP-3 (CXP-3 speed, over 100 meters) is suitable for monitoring or large-scale scene detection.

Multi channel JPEG recording: Coaxlink Quad CXP-12 JPEG, with four independent compression channels, suitable for security and motion analysis.

3D laser contour: Coaxlink Quad 3D-LLE, FPGA real-time extraction of laser line position (maximum/peak/centroid algorithm), output 16 bit height map, zero CPU usage, up to 38000 contour/second.

Large scale synchronization (multi card or multi PC): Choose models with C2C Link to achieve precise synchronization of dozens of cameras through cascading.