The innermost part of the ATLAS experiment at the LHC, CERN, will be a pixel
detector. The command messages and the readout data of the detector are
transmitted over an optical data path. The readout chain consists of many
components which are produced at several locations around the world, and must
work together in the pixel detector. To verify that these parts are working
together as expected a system test has been built up. In this paper the system
test setup and the operation of the readout chain is described. Also, some
results of tests using the final pixel detector readout chain are given.Comment: 6 pages, 10 figures, Pixel 2005 proceedings preprin