1422. File creation for unusual camera.

[Alvern]

Hello.

I'm usuing NI 1422 card and an unusual camera: 7926 x 1 px, 3xCCD, 8 bits. How can i create a configuration file for my camera in NI Camera File Creator? The maximum width i may set there is 1024 px only.

Kind regards, Alexander.

[Chris_1890]

I'd like to get a little more information about this unique camera.  What is the manufacturer, model, and scan type?  Also, are you getting an error when you try and set the width?  If so, what is the error?  If you would like to post a screen shot of your camera settings window I can take a look at it for you also.

[Alvern]

Thank you for the reply.

We created that camera by ourselves. You may see it specification here : link.

The scan type is "line scan". There are 3 CCD lines 7926 x 1px 8 bits each with different parameters (1 line for red color, 1 for green and 1 for blue).

The data from that lines goes to a onboard imaging signal processor.

At the output of the camera (and the input for the NI 1422 card) we have signals: 2 parallel stream video data and one pixel clock value.

At the input for the camera we have to send: master clock value, enable bit (consnantly "1" after switching on) and data ready bit (switching from "0" to "1" when the new frame is required). 1 frame consists of 24064 8-bits values ( 7926 x 3 + 286 values of frame header data).

We have connected these pins:

(1422) pin 1, 2, 3, 4 to (camera) Data 1, 2, 3 ,4;

(1422) pin 41, 42 (Enable A) to (camera) "enable bit";

(1422) pin 43, 44 (Enable B) to (camera) "data ready bit";

(1422) pin 91, 92 (MasterClk0) to (camera) "master clock value";

(1422) pin 99, 100 (Gnd) to (camera) "gnd".

All other pins from the 1422 card are not used.

When i'm trying to set a width "7926" in NI Camera File Creator, i press "ok" and recieve an error: "Maximum Image Size has been adjusted to accomodate the Tap Configuration you selected." and then another error: "Fatal error ccured at: NI-IMAQ: The ROI width is not properly aligned. The total number of bytes bounded by the ROI width must be aligned to a 4-byte boundary." After that the program goes back to title menu with buttons: "Create New Camera File", "Open Existing Camera File", "Help" and drop-down list with NI 1422 card selected.

Kind regards, Alexander.

[kellam]

Hi Alvern,

You have some wiring issues that you'll need to solve before you will be able to get an image.  First, you don't have any signal wired into pixel clock (pins 49 & 50).  Second, you are only wiring two data signals to the 1422, Data0 and Data1.  Since you have a 3x8 bit camera, you need to have 8 (single tap) or 16 (double tap) datalines wired up.  If your signals are differential, you'll need 16 wires (for a single 8 bit tap) or 32 wires (for 2 16 bit taps).  If your signals are single-ended, you'll need 8 or 16 wires.

Do you have a timing diagram that shows what the signals coming from the camera look like with respect to the data?  It is very non-standard for a 3CCD linescan color camera to be set up as a camera with a height of 3 - instead they are usually set up as a camera with a height of 1.  Also, you say that there are 286 values of frame header data - how is that data coming across the data lines?

With this information, we may be more likely to get you with a working solution.

-Jeff

[Chris_1890]

Alexander,

Thank you for the information.  After looking into this issue a little further, it appears that only certain values are accepted.  When I duplicated your configuration settings, I received the same errors.  However, when I set the maximum width to 8000 in the camera settings window, I did not receive any error.  When I then tried to enter 7926 for the acquisition window width, it was coerced to 7924.  If you use the increment/decrement button you can see which pixel width values are supported.  I have attached a screen shot of the settings I used which did not produce errors.

[Alvern]

Hello, Chris, Jeff

Thank you for your help.

I'm sorry, i forgot to mention that pixel clock (pins 49 and 50 on NI 1422) is also wired with camera output clock values.

The data from camera goes in 2 wires (first byte is on first wire, second is on the other one and so on, i.e.: all odd bytes goes on the 1-st line and all even are on the second one, including all header frame data) All 24064 bytes (one frame) are send at the same way.

I've tried to set a width of 24064 with height of 1 pixel, 8 bits in the Ni Camera File Creator, but recieved an error: "Fatal error occured at: NI-IMAQ: Region of interest is larger than the acquisition area."

Here is the timing diagram, i hope, it helps.

I'm also trying to find the window for setting master clock, data ready and enable bit values in Ni Camera File Creator. Could you help me with that?

Kind regards, Alexander

[kellam]

Based on what you are describing, the 1422 will not work for you.  You are describing serialized data - i.e. it takes 8 clocks to send a byte of data from each of your two channels.  The 1422 is a parallel board, and expects to receive all the bits of data for a given tap on the same clock.

-Jeff

[Alvern]

Hi, Jeff

The camera sends 1 byte of data for 1 tap (one CO/pixel clock). It just devides the data for groups by 47 bytes, depending on Data Ready (DR) signal. One byte of data goes from camera to a card every 8*To (equals to 1 pixel clock tap).

Kind regards, Alexander.

[kellam]

HI Alexander,

If I understand your timing diagram and what you are saying, you have your data group into 47 bytes for each 47x8To period.  What isn't clear to me is if there are 47 rising edges of pixel clock or 47 x 8 rising edges of pixel clock?  The 1422 would need 47 pixel clocks in that period, and would acquire data from DIN7-DIN0.  If there are 47 x 8 rising edges, then the data is serial, and the 1422 cannot acquire it.

-Jeff

[Alvern]

Hello

Sorry, that my diagram was not clear. There are 47 rising edges of pixel clock. Each edge lasts 8To (I mentioned that time just to show its connection to master clock time).

Kind regards, Alexander.