camera looking straight down - how to rotate?

I have a camera view looking straight down - what I want is to be able to rotate the view so it's still straight down, but with the user's "up" as east, north, west, south. 90 degree turns still straight down.

Can anyone tell me how to do it? Here's how I'm setting the camera view:

setCamera() { 
    //llOwnerSay("setCamera called");
    llSetCameraParams([
         CAMERA_ACTIVE, 1, // 1 is active, 0 is inactive
         //CAMERA_BEHINDNESS_ANGLE, 180.0, // (0 to 180) degrees
         //CAMERA_BEHINDNESS_LAG, 0.5, // (0 to 3) seconds
         //CAMERA_DISTANCE, 10.0, // ( 0.5 to 10) meters
         CAMERA_FOCUS, location + <0,0,-2>, // region relative position
         //CAMERA_FOCUS_LAG, 0.05 , // (0 to 3) seconds
         CAMERA_FOCUS_LOCKED, TRUE, // (TRUE or FALSE)
        // CAMERA_FOCUS_THRESHOLD, 0.0, // (0 to 4) meters
         CAMERA_PITCH, 80.0, // (-45 to 80) degrees
         CAMERA_POSITION, location, // region relative position
         //CAMERA_POSITION_LAG, 0.0, // (0 to 3) seconds
         CAMERA_POSITION_LOCKED, TRUE, // (TRUE or FALSE)
         CAMERA_POSITION_THRESHOLD, 0.0, // (0 to 4) meters
         CAMERA_FOCUS_OFFSET, <0,0,0> // <-10,-10,-10> to <10,10,10> meters
     ]);
}

The only way I can think of is, instead of looking truly straight down ( < 0, 0, -1 > ), look almost straight down, but bias it a tiny bit so that you can tweak the "up" vector as desired, e.g., < 0, 0.0001, -1 > would make global +y (north) point toward the top of the screen. The very slight deviation of the camera axis from true-vertical wouldn't be noticed.

Thank you, Deanna.

That did work - I had to make it 0.01 - at 0.0001 there was no perceptible effect and at 0.001 only a slight angle change, but 0.01 worked and still appeared "downward" enough.

I greatly appreciate the assistance!

-Kanna