  A super module assembled with MRPC detectors is a component of TOF (Time of
Flight) system for the Compressed Baryonic Matter (CBM) experiment. Before the
super modules are applied to CBM-TOF, their quality needs to be evaluated. The
readout electronics is confronted with a tremendous challenge of transmitting
data at the maximal speed of 6 Gbps. In this paper, the readout method for
CBM-TOF super module quality evaluation is presented. A parallel architecture
based on the Gigabit Ethernet is designed to meet the requirement for data
transmission rate. First, the data is sent from the front-end electronics to
four readout module groups via optical fibers at the maximal rate of 1.5 Gbps
per fiber. Next, the data are further distributed to sixteen parallel daughter
readout models so that the maximal data throughput of each daughter readout
module is 375 Mbps, within its capacity of 550 Mbps. Finally, the readout
daughter modules send data to the data acquisition (DAQ) software through
standard Gigabit Ethernet. The proposed readout method has the advantage of
good scalability, so it can meet different requirements for variable data rate.
The preliminary test result shows that each of four parallel readout groups can
transmit data at the speed of 1.6 Gbps, which indicates that the overall
readout system can meet the requirement for the maximal data-transmission speed
of 6 Gbps.
