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CAMAC standard crates and modules continue to be used for nuclear and high energy physics experiments and test setups. They provide unbeaten performance in high precision measurements, flexibility and simplicity in the design of modules. We have designed and fabricated a new type of CAMAC crate controller with list processing capability to maximize the data throughput, event rate handling capability, while simultaneously simplifying software development efforts for data acquisition systems, also maintain complete compliance with CAMAC standards and ability to utilize all existing CAMAC compliant modules. The throughput increase is achieved by eliminating the arbitration between the CAMAC crate controller and list processing modules by integrating the list processor ͑auxiliary crate controller͒ and the crate controller. The event rate handling capability is increased by advanced list processing techniques such as Q-stop and hit-pattern based list processing. The resulting ethernet based list processing crate controller can transfer up to 1700 kbytes/s reaching up to hundreds of kilo events"s in 16 bit transfer mode from CAMAC modules measured at the analysis engine end. This makes it suitable for use in experimental systems, where a large number of signals with high event rates need to be collected with high precision.

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Nuclear and particle physics experiments with large number of detectors require signal processing and data collection strategies that call for the ability to collect large amount of data while not sacrificing the precision and accuracy of the data being collected. This paper deals with the development of a high precision pulse peak detection, analog to digital converter (ADC) module with eight independent channels in plug-in daughter card motherboard model, best suited for spectroscopy experiments. This module provides multiple channels without cross-talk and of 14 bit resolution, while maintaining high density (each daughter card has an area of just 4.2(")x0.51(")) and exhibiting excellent integral nonlinearity (< or = +/-2 mV or +/-0.02% full scale reading) and differential nonlinearity (< or = +/-1%). It was designed, developed and tested, in house, and gives added advantages of cost effectiveness and ease of maintenance.

The demands from current data acquisition systems are to acquire data from a large number of detectors (or signals) while providing a high throughput. This can be achieved by having some preprocessing capability in the data acquisition system so that it can identify the events of interest. Precise selection of events with minimal time for identification and preprocessing is an experimental challenge. To address this challenge, we have developed a "Global Event-identifier Module" (GEM) on the CAMAC platform, which can flexibly adapt to the experimental requirements and validate an event with minimal time. GEM is a single width CAMAC module capable of operating in a "distributed" data acquisition environment where multiple CAMAC crates (each with one GEM module) can be used to collect synchronized data from all the crates. Event-of-interest decision can be made on signals connected to different crates. Inter-GEM communication is via the ubiquitous ethernet (unshielded twisted pair, CAT5) cable. The event of interest is decided within 32 ns (excluding cable delay). Implementation is accomplished using field programmable gate array which enables greater flexibility for algorithm modifications and updates without hardware changes. GEM supports unified, distributed, and multi-strobe data acquisition, enabling higher throughput, with data collection from a large number of signals by selective reads of events of interest as determined by the experimenter while providing timestamped data of each event.