This page uses nested frames within the same HTML document file. This HTML page contains a frameset with 2 frames, one on the left and one on the right. This frame, the one on the left, has the frame name frameset_2. Inside frameset_2 is another set of frames. This is the top frame in frameset_2 and it has the frame name control_frame.

JavaScript frame calls that do work:

Write to this current frame using top.frames[0].document.writeln()
Write to this current frame using parent.frames[0].document.writeln()
Write to top using parent.parent.parent.frames[0].document.writeln()

Write to bottom_target using top.bottom_target.document.writeln()
Write to bottom_target using top.frames[1].document.writeln()

Write to right_target using top.frames[2].document.writeln()
Write to right_target using parent.frames[2].document.writeln()
Write to top using parent.parent.parent.frames[2].document.writeln() There is no such frame

JavaScript frame calls that don't work:

Write using top.frames[0].bottom_target.document.writeln() There is no middle frame[0]
Write using top.frames[0].frames[1].document.writeln() There is no middle frame[0]

The following are never possible because to work, they would have to link from within a frames page. Frames pages never have body tags or any other text that is viewable by the browser, and therefore could not display these links.
Write using frames[1].document.writeln()
Write using right_target.document.writeln()
Write using bottom_target.document.writeln()

Click here to see the FDT based on JavaScript frame numbering

Testing