Glossary

detChan

A global value unique to each channel in the system. The detChan value is used to reference a channel independent of the module it is associated with. Furthermore, detChans may be grouped into detChan sets that are also given a unique value and may be used with most routines that accept a detChan as an argument. Additionally, detChan sets may reference both single detChans and other detChan sets, provided that none of the detChans refer back to the original set. Handel checks the integrity of the detChans and warns the user if it detects an infinite loop.

Driver Libraries

Each XIA product requires two driver libraries:

• an interface to the hardware at a low level (device-driver) and

• an interface that provides the device specific implementations. (PSL driver).

DSP

This is the on-board digital signal processor (DSP) that controls the spectrometer functions and some general run functions. The DSP also contains memory for storing spectra, diagnostics, control words and an internal work area. The host computer must download a program to the DSP prior to starting tasks on the XIA processor. This device is complicated and XIA provides programming manuals for custom applications. A “standard” DSP program is provided with all XIA processors.

Firmware Definition Database (FDD)

XIA will release firmware in special files created for Handel, called FDD files. Each file will contain all of the Firmware code required to configure and run an XIA processor. Special firmware will be distributed as FDDs separate from the general distribution.

FiPPI

This is the field programmable gate array (FPGA) in which the Filter, Peak detection, Pileup Inspection logic is implemented. Like the DSP, a configuration file must be downloaded to the FiPPI before it can function.

Firmware

Firmware refers to all FPGA(s) and DSP(s) on the XIA processors. When power is initially applied to an XIA processor, it has only enough firmware loaded to handle communication via the hardware interface; the rest of the firmware must be downloaded to the XIA processor prior to starting tasks.

Hardware interface

This is the method that each XIA module uses to communicate with the host computer. We currently support USB2 and serial ports on most Linux and Windows operating systems. PLX is supported on Windows. USB1 and EPP support remain in the codebase but are no longer tested by XIA.

Host

This is the computer on which the data collection program runs and collects data via some hardware interface to the XIA device.

.ini File

The .ini file is used by Handel to initialize the system, several options for initializing are available and discussed later in this document.

Memory Manager

See System Chip.

Module

XIA product with at least one channel associated with it.

Product-specific Layer (PSL)

A set of libraries that libraries contain the individual logic associated with each product. Host software should never call these libraries directly.

Read

Transfer data from the XIA processor to the host computer.

Write

Transfer data from the host computer to the XIA processor.

System Chip

This is another FPGA that is present on some XIA processors. Its function is to control miscellaneous chips on the processor such as SRAM and FIREWIRE interfaces. As XIA processors evolve additional FPGAs may be added.