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CATAVIÑA is a near-infrared camera system to be operated in conjunction with the existing multi-purpose nearinfrared
optical bench "CAMALEON" in OAN-SPM. Observing modes include direct imaging, spectroscopy, Fabry-
Perot interferometry and polarimetry. This contribution focuses on the optomechanics and detector controller
description of CATAVIÑA, which is planned to start operating later in 2006. The camera consists of an 8 inch LN2
dewar containing a 10 filter carousel, a radiation baffle and the detector circuit board mount. The system is based on a
Rockwell 1024x1024 HgCdTe (HAWAII-I) FPA, operating in the 1 to 2.5 micron window. The detector
controller/readout system was designed and developed at UNAM Instituto de Astronomia. It is based on five Texas
Instruments DSK digital signal processor (DSP) modules. One module generates the detector and ADC-system control,
while the remaining four are in charge of the acquisition of each of the detector's quadrants. Each DSP has a built-in
expanded memory module in order to store more than one image. The detector read-out and signal driver subsystems
are mounted onto the dewar in a "back-pack" fashion, each containing four independent pre-amplifiers, converters and
signal drivers, that communicate through fiber optics with their respective DSPs. This system has the possibility of
programming the offset input voltage and converter gain. The controller software architecture is based on a client/server
model. The client sends commands through the TCP/IP protocol and acquires the image. The server consists of a
microcomputer with an embedded Linux operating system, which runs the main program that receives the user
commands and interacts with the timing and acquisition DSPs. The observer's interface allows for several readout and
image processing modes.
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