Development of the MDT RODs (MROD) at NIKHEF

The MROD (MDT Read Out Driver) has to build event fragments from the data of 6 MDT muon chambers.

On each muon chamber the data of at maximum 18 TDCs, with 24 channels each, will be multiplexed by the Chamber Service Module (CSM) on one Gigabit Optical Link (GOL) using the GOL chip, so the MROD has 6 inputs for these links and one source S-link interface for the Read-Out Link (ROL) to be connected to a ROB (Read-Out Buffer) . The MROD-1 design consists of a 9 U VME board with 6 inputs, each with a connector for a S-link destination card, one source S-link interface, a VME64x interface and an interface to the TTC system. The design makes use of SHARC-II processors (ADSP-21160) in conjunction with Altera FPGAs. Links based on the GOL chip as well as standard S-links can be connected to the inputs using appropriate daughter boards.

The MROD-X design builds upon the MROD-1 design. In it the Altera FPGAs are replaced by Xilinx FPGAs, which are connected with "RocketIO" links. Although the MROD-X can be used in an MROD-1 compatible mode, during normal operation event data will be transported via the "RocketIO" links and fragment building is done in the FPGA connecting to the output S-link, while the SHARCs take care of control and monitoring. The MROD-X occupies a single VME slot and has 6 or 8 (prototypes only) inputs for GOL links. There are no daughter boards, except the obligatory S-link source card for the Read-Out Link. Six fully-functional prototype modules are available, a picture of the assembled PCB is shown below. The Production Readiness Review has taken place on 2 November 2005, the production of about 255 modules with 6 inputs is under way, a pre-series of 15 modules is fully functional.

Picture of MROD-X PCB

MROD-X prototype, component side

MROD test setup

December 2006: pre-series of 15 modules under test in a VME crate. 12 modules send data from internal test generators to a ROS PC via the optical fibers connected to the S-link daughterboards. On the display the IGUI used for controlling the ROS PC can be seen, together with the terminal windows used for starting the software on the MRODs (during normal operation the MRODs are controlled directly by the ROD Crate DAQ software). The fibers connecting to the GOL link inputs (upper half of modules) are loopback fibers: in test mode bi-directional operation of the links is possible and used for sending simulated event data from one"input" to another input. Modules without loopback fibers use internal (electrical) loopback. Error free operation at 100 kHz event rate has been observed.

installation activities in USA-15

26 January 2007: installation activities in USA-15. Twelve pre-series modules have been installed.

For further information on the MROD-X click

Overview paper: H. Boterenbrood et al., IEEE Trans. on Nucl. Sci, vol. 52, no. 3, pp. 741 - 748, June 2006.

February 2006
: Results of temperature tests

Documents for Production Readiness Review of 2 November 2005 (Agenda review meeting)

Slides for Intermediate Design Review of 12 November 2003 (Agenda review meeting)

Links to documents

Links to relevant web pages

The first design for the MDT ROD was the NIMROD.

Jos Vermeulen,, 2 February 2007