mouse move in another frame

[Stuart]

The following code works well in monitoring the mouse position in its own
frame, I need to capture the mouse position when it is over another frame,
What is the correct syntax?

There is two frames one named "upper" and one named "slave" all my coding is
within the upper fame and I need to capture the mouse position when the
mosue is above the frame named "slave".....I have been using
"parent.slave.document" but ain't getting anywhere!

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document.onmousemove = getMouseXY;
var tempX = 0
var tempY = 0

function getMouseXY(e) {
tempX = event.clientX + document.body.scrollLeft
tempY = event.clientY + document.body.scrollTop
status=tempX+' '+ tempY
return true
}

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