Interfacing the JAI CV-A1 With the IMAQ 1409

This article explains how to interface the high-resolution JAI CV-A1 progressive scan camera with the National Instruments IMAQ 1409 image acquisition device.

Introduction

The JAI CV-A1 is a nonstandard, high-resolution analog camera that provides 16 images per second and has a resolution of 1380 x 1035 pixels. Because the JAI CV-A1 provides a high-frequency 28.63636 MHz pixel clock (corresponding to a line frequency of 17.127 KHz), the phase-locked loop circuitry of the IMAQ 1409 cannot internally synchronize with the HSYNC of the incoming video signal. As a result, it is not possible to use a standard configuration file or to acquire images by connecting the video output of the camera to the input of the IMAQ 1409.

The IMAQ 1409 supports the JAI CV-A1 camera in external lock mode. In this mode, the IMAQ 1409 device receives HSYNC, VSYNC, and PCLK signals from the camera and uses these signals to acquire the video signal.

For more information about the acquisition modes of the IMAQ analog devices, refer to the Using the Acquisition Modes of Analog IMAQ Devices document.

Camera Switches Setup

This section explains how to set up the JAI CV-A1 camera.
Note: This section requires that you modify internal camera switches and jumpers. If you are unsure of how to modify internal switches and jumpers, contact JAI technical support for more information.

Figures 1 and 2 show the locations of the internal camera switches and the JP2 jumper. Table 1 at the end of this section summarizes the camera switch configuration. These settings are valid for revision A of the JAI CV-A1.

Make the following modifications to the internal camera switches:

• Verify that switch SW1-1 on PK8342A board is set to the IN position to input the vertical synchronization signal (VSYNC). This setting is the factory default. The Write Enable (WEN) signal connects to the IMAQ 1409 VSYNC.
• Set switch SW1-2 on PK8342A board to OUT to output the horizontal synchronization signal (HSYNC).
• Verify that switches SW2-1 and SW2-2 on PK8342A board are set to the off (lower) position to set the termination of the external synchronization signals to TTL. This setting is the factory default.

• To use pixel clock pulse output, short-circuit jumper JP2. This jumper is located on the board at the connector end (back) of the camera. Pixel clock pulse is output from pin 9 of the 12-pin multi-connector.

Summary: Camera Settings
Table 1 below offers a quick reference for adjusting your camera settings.

Table 1: Internal Switches and Jumper Settings

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Cabling Requirements

This section discusses cabling and power supply requirements for use in free-running mode. Figure 3 shows the schematics for using the National Instruments IMAQ-A6822 breakout box to easily prototype your cable.



Figure 4 shows the cable schematics for the JAI CV-A1 and the IMAQ 1409.


Tables 2, 3, and 4 outline the requirements for the power supply, connecting the IMAQ 1409 to the JAI CV-A1, and connecting the PC serial port to the JAI CV-A1.

Table 2: Power Supply

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Note: National Instruments recommends using a 26-gauge shielded twisted pair for the power supply.

The IMAQ 1409 operates in external lock mode. This mode requires that you provide the horizontal and vertical synchronization signals, the pixel clock, and the video signal to the IMAQ 1409.

Table 3: Connecting the IMAQ 1409 to the JAI CV-A1 (12-Pin Hirose Connector)

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Note: National Instruments recommends using 30-gauge shielded twisted pairs for the timing signals. Because this cable transmits high-frequency signals similar to the pixel clock, National Instruments recommends limiting the length of the cable to 4 meters to preserve the quality of the signal and to limit the attenuation.

Table 4: Connecting the PC Serial Port to the JAI CV-A1 (6-Pin Hirose Connector)

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PC Serial Port (DSUB9) Loopback Connections

1. Connect pins 1, 4, and 6 of the DSUB9 connector. These pins correspond to the Data Carrier Detect, Data Terminal Ready, and Data Set Ready signals, respectively.
2. Connect pins 7 and 8 of the DSUB9 connector. These pins correspond to the Request to Send and Clear to Send signals, respectively.

   Interfacing With the IMAQ 1409
   

This section explains how to configure your hardware and software to acquire images with the JAI CV-A1.
Note: Before configuring your software, make sure to remove the W1 jumper on the 1409 device.

1. Download and install the camera control utility from the JAI Web site.
2. Launch the JAI A1 control utility, and click Start>>Programs>>CV-A1 Control Tool>>CV-A1 Control Tool.
3. Click the Shutter and Sync Signals button.
4. Set the Pixel Clock Out radio button to On to output the pixel clock.

Configuration Files
1. Copy the JAI CV-A1(1409).icd file into the <NI-IMAQ>\Data folder. Go to ftp://ftp.ni.com/support/imaq/camera_support/camera_files/analog/jai/ to download this camera configuration file.
2. Launch Measurement & Automation Explorer (MAX).
3. Expand the Devices and Interfaces branch of the tree view.
4. Expand the IMAQ PCI/PXI-1409 branch of the tree view.
5. Right-click Channel 0: RS-170, and select Camera>>JAI>>JAI CV-A1.
6. Click Save.
Related Links:
Using the JAI CV-A1 Camera in Asynchronous Reset Mode with the IMAQ 1409

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