EL-3420Signal Assignments
The signal assignment section of this manual contains descriptions of the signal assignments for the new HIRES CCD Controller. It corresponds to the Signal tab in the electronics schematics binder.
Utility board signal assignments,
EL-3420
In the above table are the signal assignments for the signals coming from the SDSU Utility board. The columns are organized to show the pins on the 96-pin DIN connector that connects the Utility board to the UCO/Lick Utility Support board. Although the connector has 96 pins, the interconnect cable only passes 64 of these due to the spacing of the ribbon cable. This results in the use of the 'A' and 'C' rows of pins of the DIN-96 connector. On the table, the left-hand column holds the pin number. The rest of the table is divided into two sections, the 'A' pins and 'C' pins.
Pins A1 and C1 pass the -16V and +16v supply voltages of the Utility Support board back to the SDSU Utility board. Pins A18, A26, C18, and C26 are the analog grounds for the power supply voltages. Pins A2 through A17 are the general-purpose digital outputs that the SDSU Utility board provides. We use Dout3 through Dout6 on pins A3 through A6 for select lines that allow us to read back any of the 12 bias voltages that are sent to the CCD dewar electronics box. The bias levels are each brought to an analog multiplexer on the EL-3194 61-pin Cable Interconnect at the back of the chassis. The software can then, via these select lines, read back any of the bias levels that are being sent out to the CCD.
Pins A7, A8, and A9 are the CCD select lines. These are used when multiple CCDs are used in the system to uniquely select one of individual CCD chips. Used in conjunction with the Bias Select lines above, the software can read back any of the bias levels set on any of the CCDs.
Pin A11, Dout14, is used to turn on and off the cooling fans for the electronics footlocker. The signal is applied to a solid-state relay that controls the 115V AC to the fans.
Pins A12, A13, and A14, Dout11 through Dout13, are used in systems that require additional heater circuits as in the case of a CCD array. These signals allow the software on the Timing Board to write values into DACs on the Utility Support board that can be applied to the different CCDs. This might be used if, for instance, to keep a backplane at the same temperature. (See EL-3193 sheets 5 and 6)
Pin A15, Dout10, is used by the software to turn on the analog switches in the dewar electronics box. This is labeled as a request because the final signal to enable the switches is generated on the EL-1198 Power Monitor board. If the conditions are correct to allow the switches to turn on the Power Monitor board passes this signal. The output that actually goes to the switches also comes back through this connector on pin C17, Din8, so the software will know the actual state of the switches.
A16 and A17, Dout10 and Dout9, are used to tell the Power Monitor board that the software is up and running and it is OK to turn on the +/-16V and +35V supplies to the VME backplane.
Pin A18 is an analog ground. This ground is wired to the Utility Support board.
Pins A19 and A20 are serial I/O lines that we do not use. A21 has no connection.
Pin A22 routes the External Reset line from the Power Monitor board back to the SDSU Utility board. This signal is asserted if the +5V power supply fails,
Pin A23 is a ground. This ground is wired to the Utility Support board.
Pin A24 is an analog output that we are currently not using.
Pin A25 is used when a local temperature readout is required on the CCD controller. In the case of HIRES, it is not used.
Pin A26 is a ground. This ground is wired to the Utility Support board.
Pin A27 is a current source that is used to drive the temperature diode in the dewar.
Pins A28 and A29, Ain14 and Ain12 are analog inputs that are not used.
Pin A30, Ain10, is an analog input and it used to read back the temperature diode inside the CCD dewar. In multiple CCD applications, different temperature diodes may be read by setting the CCD Select lines to the proper values.
Pin A31, Ain8, is used to monitor the output of any of the clock signals generated in the CCD controller. Each of the SDSU2 Clock Generation boards has the ability to, via software, monitor any of its clock lines and pass it to a SMB coax connector on the front of the board. We route the coaxes to the Utility Support board and apply them to a analog multiplexer. By setting the CCD Select lines to the proper values, clock board outputs can monitored via this pin.
Pin A32, Ain6, is used to read back a second temperature diode if used.
Pin C1 is used to route the +16V supply voltage to the SDSU Utility board.
Pin C2, Din7 is used to monitor the 'Manual Fill' pushbutton switches. There is a pushbutton at the 50L dewar and one at the CCD dewar. If either of these are pushed the software will cause the auto fill system to pressurize the 50L dewar which will force LN2 into the CCD dewar. For more info, see EL-3415.
Pin C3 through C6, Din3 through Din6, are not used at this time.
Pins C7 and C8, Din2 and Din1 are used to monitor the positions of the two transfer valves mounted upon the 50L dewar. These valves control the filling of the 50L dewar and are monitored to ensure that if they are accidentally left in the wrong position after a fill operation that the software will be able to alert the operators.
Pin C9, Din0 is used to monitor the shutter's limit switch. The switch indicated when the shutter is open. Realise that it doesn't mean that the shutter is completely closed if the signal goes high. This only means that the open limit is not tripped but not that the shutter has closed all of the way!
Pins C10 through C16 are not used.
Pin C17, Din8, is used to monitor the state of the analog switches. This signal is generated on the Power Monitor board.
Pin C18 is a ground. This ground is wired to the Utility Support board.
Pins C19 and C20 are serial data inputs. We do not use these lines. C21 has no connection.
Pin C22, SHUTTER, is the shutter control signal. When high, the shutter is open and when low the shutter is closed. This signal is routed out to the EL-3404 Power and Miscellaneous Signal board and then out to the EL-1093 Shutter Controller.
Pin C23 is a ground. This ground is wired to the Utility Support board.
Pins C24 and C25, Aout1 and Aout0, are heater outputs. The SDSU Utility board uses these lines to warm up a heater resistor in the dewar to regulate the temperature.
Pin C26 is a ground. This ground is wired to the Utility Support board.
Pins C27 and C28 are analog inputs that are not used at this time.
Pin C29, Ain11 is used to monitor the LN2 level in the CCD dewar. The level is monitored via a special tri-axial sensor. More info is availabe on the dewar fill schematic EL-3415.
Pin C30, Ain9, is used to read in the level of the bias voltage that is selected via the Bias Select lines.
Pin C31, Ain7 is used to monitor the LN2 level in the 50L dewar. The level is monitored via a special tri-axial sensor. More info is availabe on the dewar fill schematic EL-3415.
Pin C32, Ain5, is used to read back the temperature diode that is mounted inside the dewar near the CCD.
Schematic: schematics/utilcon.sch.pdf
Page last updated: July 16, 2004