DSP Hardware Description

  • A 486DX 33MHz rackmountable PC running ESIX 4.0.4 SVR4 compatible UNIX.

  • UR Near Infrared 3rd Generation dewar.

  • The small(new) Silver Box contains a Preamp card, Wallace and Special Bias cards and a DC Level Shift card. The larger(older) version of the Silver Box has three DC Level Shift cards instead of one.

  • A Data Translation DT2823 which handles analog I/O and digital output. We use this board to set bias and gate voltages (D/A 0,1), monitor the dewar temperature (A/D 0-3) and to control the filter wheel stepping motor.

  • A Spectrum DSP56000 Processor board which generates detector clocking signals, A/D convert signals and synchronizing signals for the system.

  • Two Spectrum DSP56000 System boards (up to six are allowed) which collect data from the detector array. Each board is capable of measuring up to 2 channels of output from a detector.

  • The Jimm-Bruce I/O Clocking board (Bruce Pirger and James Garnett) takes input from the Spectrum Processor card. Most of the input is used to create the correct patterns of voltages for the clocking signals. The I/O Clocking board sends an ADC pulse to both A/D conversion boards via the twisted pair (red & green) wire inside the computer which helps keep the A/D boards in synch with reading the signals from the array. It also sends a 5V power on signal to the DC Level Shift card inside the Silver Box.

  • Two A/D conversion boards which convert the analog data from the dewar/Silver Box to digital signals for processing by the Spectrum System boards.