Design and Implementation of an Universal Read Out Controller

Since 2007 our contribution focused the Silicon Tracker’s FEE (Front End Electronic), consisting of the nXYTER, an ADC (Analog Digital Converter) and a ROC (Read Out Controller) [1]. The implementation of the nXYTER specific ROC has been done very successfully, as the beam tests in September 2008 [3] and September 2009 [2, 4] proved. Our first ROC setup consisted of the nXYTER readout logic and a PPC based Ethernet transport logic. This setup is called the nXYTER Starter Kit, which turned out to be very helpful in small laboratory setups, where physicists need quick access to the nXYTER and its measured data. The Ethernet interface keeps the communication effort as simple as possible, since every common PC supports it. However, in the final experiment thousands of ROCs will be used. In this setup Ethernet will not be an option any longer. This is primarily caused by the galvanic isolation coming with fiber optics and by the fact that the certain ROCs are synchronized via Deterministic Latency Messages (DLMs), which by definition depend on optical fiber [5]. Thus, a second transport logic, the Optical Transport, has been implemented. In our first concept, the Optical Transport was planned to fully replace the Ethernet transport. Due to the usefulness of the Starter Kit this plan has been altered. Today, we fully support both, Ethernet and Optical Fiber, as two equal solutions.