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Total Data Readout (TDR) is a powerful data acquisition tool developed for use with Recoil Decay Tagging (RDT) experiments on the GREAT (Gamma, Recoil, Electron, Alpha Tagging) spectrometer. RDT experiments correlate prompt radioactive decays detected at the target position with subsequent decays of recoiling reaction products implanted in GREAT, located at the focal plane of the RITU recoil separator, several microseconds later. TDR uses independent channels associated in a software event builder based on timestamps to form a single time ordered data stream. It is crucial to maintain the accuracy of the timestamps over long periods (microseconds to hours) for the study of Exotic Nuclei. The TDR system cannot be tested fully by use of calibrated sources with GREAT and a novel method of verifying the system is required. Our solution is to use the predictable randomness of a Pseudo Random Number generator based on Linear Feedback Shift Registers (LFSR) implemented in a 16 channel VME module. The random value defines the delay between pulses into the TDR system. The recorded results are sorted and checked for correspondence with the LFSR sequence. We show the method, design of the module, and discuss the results and benefits of the tests

A four channel VME card with 14 bit, 80 MHz digitizers and powerful on-board processing has been designed, built and used in tests of digital pulse processing techniques for gamma-ray tracking. This paper explains the background (rationale for the project), describes the VME card (known as the GRT4) and presents a 64 channel GRT4 digitizing system which was used to instrument two segmented Germanium detectors during in-beam tests. Results obtained using the GRT4 card are presented as well as some applications.