RED side

    The red side uses a Tek1x1K CCD. It is being controlled by a Fred Harris (FHH) Palomar controller, which is in turn connected to a CCD8 camera controller that can run up to 4 diferent FHH controllers.

    The FHH controller receives commands from the CCD8 camera controller and sends data and CCD temperature back through the same link. The CCD8 camera controller is connected to a PC running Linux using a PCI interface card ( EDT P11 W).


BLUE side

    The blue side is a little bit more complex. It has a 2x4K E2V CCD, which is being controlled by a San Diego State University Controller (SDSU) generation III.

    The SDSU controller receives commands and sends data back to a PC running Linux, through an optical link connected to the  SDSU-III PCI card (ASTROPCI), and it is connected to the CCD throug a flex circuit that carries to the detector the requiered biases and  clocks, and brings back analog video data. The CCD mount has a temperature sensor that is being read also through the flex circuit. This signal is not converted to temperature in the controller itself, but gets passed to the Lakeshore Temperature controller , along with the readings of two temperature sensors mounted on the SDSU controller itself.

    The Lakeshore controller has also a direct connection to the dewar to read another two temperatures (Neck and LN2 can), and also to bring power to the two heaters installed there (LN2 can and CCD mount). In this way (reading the temp. and bringing power) the Lakeshore controller can set the temperature of the CCD to a requested value (detector setpoint)

    Both SDSU and Lakeshore controllers are being powered through a Network Power Switch (NPS ) that allows reseting them through the network if needed.

    The Lakeshore controller has a serial port (RS232) that is connected to a Terminal Server. This configuration allows the Lakeshore to be accesed through the network without the need of a direct conection to the PC.


Instrument

    There are four  aspects of the instrument that can be controlled or read automatically.

-Polarimeter: This is not still being controlled by the software, thoug it is possible. The next version of the software will incorporate  this capability
- Aperture, Filters: The aperture and filters (for both red and blue sides) are being controlled manually by the user (no software interface). The instrument controller that actually moves the parts sends the position of both, aperture and filter, through a serial line, every time there is a change. This serial line allows only to read the positions, but not to control them.
The serial line is currently directly attached the a PC running Linux.
- Shutters: the BLUE shutter is connected to the SDSU controller. The RED shutter is connected to the CCD8 camera controller.


Host Computers

    The main host computer (acquisition) is a PC running Linux. This machine is connected to both detector controllers ( FHH and SDSU) throught two PCI cards (ASTROPCI and EDT P11W). Besides that, it is connected through a serial line to the instrument controller to receive asynchronous status on aperture and filters.
This computer is controlling and reading the Lakeshore temperature controller through the network (accesing the Terminal Server).

    The acquisition host is also connected to the Telescope Control System (TCS)  of the 200 inches telescope through the network, in order to read information for the image headers, and to control the calibration lamps

    Finally, there is a second computer (reduction PC ) that is connected to the acquisition host in order to pull out the acquiered images