May 14, 2001
R. Millan-Gabet

New Star Tracker Interface
==========================

It was found in December 2000 that due to the long cable between the
VME rack and the CCD electronics, the readout of the CCD using the
FPGA was not working properly. A new interface was designed following
suggestions by Ettore, and built by Marc. The basic idea was simply to
use drivers/receivers for the logic signals and data, and a cable
consisting of shielded twisted pairs.

Tests of the CCD readout using this new interface proved that it all
works fine, provided we power the interface box at the CCD end with
its own 5V DC supply, and not using 5V from the CCD electronics rack
itself.

See the e-Blueprint library for schematics of the interface (VME and
CCD sides), cables and pinouts.