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Interfacing the PULNiX TM-6705AN

progressive scan camera to the MV-1000

The M-Vision-1000 (MV-1000) is a monochrome digitizer board, which interfaces to the PCI bus. The MV-1000 provides a timing generator capable of generating control signals such as horizontal drive (HD) and vertical drive (VD). One megabyte of VRAM is present on the MV-1000 for temporary image storage.

TM-6705 Camera

The TM-6705AN camera from PULNiX is a high resolution, progressive scan 768 H x 484 V full-frame camera with asynchronous reset capability and continuous video output. It can also output interlaced video. The TM-6705 provides a wide variety of operating modes, including manual or controlled electronic shutter, interlace or progressive scan output, partial scan capability, multiple shutter, and integration. This application note focuses on the progressive scan, partial scan and multiple shutter modes.

Cable Connections

The 12-pin DIN connector on the TM-6705 provides power to the TM-6705. It also has a connector for video (red, pin-4) and a group of control signals. These control signals are discussed in the TM-6705 technical reference as well as in further sections of this application note.

The MV-1000 attaches to the TM-6705 via an MVC-7 cable. Different wiring configurations are required for different operating modes. These cable configurations are shown in Figure 1. Figure 1a shows a cable configuration where the MV-1000 provides HD and VD to drive the TM-6705. Figure 1b adds a connection to allow Asynchronous Reset to be sent to the TM6705 from an external source. Figure 1c shows a method to connect Asynchronous Reset to the VD signal from the MV-1000 where the period and duty cycle of VD will be altered to control the number of lines readout per frame in Partial Scan mode. Figure 1d shows another configuration where VD is used to fire the Multishutter control when ROI is controlled externally. Figure 1e illustrates how external Integration is connected while the MV-1000 drives HD and VD.

Figure 1c. TM-6705 cable configuration driving HD and using VD to drive VINIT to control Partial Scan.

Figure 1d. TM-6705 cable configuration driving HD and using VD to drive Multishutter control with external ROI control.

Figure 1e. TM-6705 cable configuration driving HD and VD with external integration control.

Jumper Settings

The jumper settings on the MV-1000 that need to be modified from factory default are:

JPD3-IN to connect VD to pin 5.

JPD5-IN to connect HD to pin 4.

JP13-IN to connect HD to pin 5 without an AC coupling capacitor.

JP10-OUT to remove termination load from HD.

The full jumper configuration is given in the tm6705.jmp file.

From a software point of view, the concept of video acquisition from standard or non-standard cameras is based on the use of a Camera Configuration File. Camera "Config" files are ASCII files that hold all of the values relevant to the proper usage of a particular camera with the MV-1000.

Camera Configuration files for most commercially available cameras are available from MuTech either on a distribution diskette or via the World Wide Web at http://www.mutech.com. All MV-1000 distribution software use these Camera Config Files to set the board and chip registers into the correct state to work with a particular camera. Several Camera Configuration Files for the TM-6705 are available as examples. Users may adjust some parameters to control timing.

Critical Parameters for the TM-6705 include:

[General Control] section

Tim_Gen_Enable=1 Must be turned on to drive HD or VD. If no special modes are used, this may be zero and the MV-1000 will just lock to the TM6705AN.

[PLL Control] section

H_Period=31.78

Pixel_Per_Line=810

Clock_Reference_Select=0

Force_EQ_Remove=1

This section controls the PLL timing. There should be 810 pixel periods in each 31.78 m sec horizontal line. The external horizontal sync will be used for the fundamental timing standard.

[Grab Window Control] section

V_Offset=16

V_Max_Capture_Size=50

The TM-6705 delays 16 lines prior to active video transfer. The V_Max_Capture_Size may vary up to 484 lines. If V_Max_Capture_Size is too big, no capture will occur. This will only become a problem if partial frame mode is being used.

[Timing Generator Control] section

Camera_Pixel_Per_Line=810

Camera_Line_Per_Frame=150 ; used for VINIT in partial transfer

Camera_Drive_Height=71

Partial Scan

The Camera_Pixel_Per_Line should remain the same as the PLL pixel count if HD is being driven. Camera_Line_Per_Frame is critical to the timing of the VINIT for partial scan. Camera_Drive_Height defines the number of lines to transfer. When using partial scan remember two caveats:

1) The partial scan always starts with 32 blanking lines followed by the first line in the camera.

2) After the lines of interest are transferred, VINIT must go HIGH for a fast dump period to drain the remaining lines. The fast dump will process the untransferred lines at 2.5 m sec per line.

What this means is that for partial scan, you need the VINIT in LOW for at least (32 + number_of_lines_to_transfer) * 31.78 m sec, then VINIT in HIGH for at least (488 - number_of_lines_to_transfer) * 2.5 m sec. Camera_Line_Per_Frame must be at least number_of_lines_to_transfer + ((488-number_of_lines_to_transfer)/(31.78/2.5)) lines long.

Multishutter

The configuration for this mode is illustrated in Figure1d. This mode uses pin 10 (MS) of the 12-pin Hirose connector on the camera as a shutter fire when pin 11 (ROI) of the same connector is held LOW. Thus, while ROI is held low by some external switch or signal source, each time the MS goes high causes another image to be summed into the CCD array. The MV-1000 Timing Generator can provide evenly spaced MS pulses via the BLACK (VD) connection of the MVC-7 cable. Alternately, the MS pulses can be externally generated and the VD can be routed to pin 7 (VD) on the camera.

Then, when the ROI goes HIGH again, the accumulated image is transferred to the MV-1000. The application program monitors the state of the ROI line which is connected to the TRIGGER line (YELLOW on the MVC-7) to determine when to capture the accumulated frame.

Asynchronous Reset

Asynchronous Reset mode occurs when ASY switch is selected on the camera and VINIT (pin 11). Here the MV-1000 supplies HD (GRAY on MVC-7) and VD (BLACK). The VINIT signal will normally come from an external device to initiate the capture and transfer of the frame from the TM-6705 and to signal TRIGGER (YELLOW on the MVC-7) to the MV-1000.