The computer-controlled hardware for alignment and data collection is outlined in figure 2 (section 1) and consists of a germanium solid-state detector with associated power supply and preamplifier, a Canberra series 35 multichannel analyzer. The motor drivers are controlled by a series of CAMAC modules, listed below. See sections 1.2.2.2 and 1.2.2.3 for connections. The equipment supplied by the beam line (the upstream apertures, the 4-jaw slits, and the Huber 4-circle) diffractometer are controlled by another CAMAC crate with a SCSI crate controller. Both crates are controlled by a 3100 VAXstation computer.
This help file can be accessed by HE HX
The SAM85 program uses the following CAMAC modules.
Slot 1. IO612 Input/output register, two 24 bit registers.
Slot 5. E500: Module #1 controls the first eight motors. The coordinate system that is used has +X in the direction of the X-ray beam, +Z up, and +Y for a right handed system. For rotations, plus is clockwise when looking down on the press. Each motor is assigned as follows:
Mtr Symbol Description
1 SY Y motion of entrance slit
2 SZ Z motion of entrance slit
3 TT 2q
4 BZ One of three base Z motors
5 none One of three base Z motors
6 none One of three base Z motors
7 BY Base Y
8 BO Base Phi
Slot 6:. E500 Module #2 controls the second eight motors.
9 PX Pedestal X
10 PY Pedestal Y
11 PZ Pedestal Z
12 PO Pedestal Phi
13 PV Pressure Valve
14 IP Imaging Plate translation
15 Undefined
16 Undefined.
Slot 7:. E500 Module #3 controls the third group of eight motors (4 of which are used).
17 C1 Camera Y
18 C2 Camera Z
19 C3 Camera X
20 C4 Conical Slit rotation
Slot 18. 3655 Timing generator: This module controls the time for all counting operations.
Slot 20. 3610 Hex scaler: This is a six channel counter. The channel assignments are as follows:
1 Heater Voltage
2 Heater current
3 Heise pressure gauge
4 SCA for secondary ionization chamber
5 SCA for primary ionization chamber
6 SCA for monochromatic data collection
Slots 21 & 22. 3388 GPIB Interface, an IEEE 488 interface; logically slot 22.
9. 3922 parallel crate controller, slot 24.
If it is necessary, any of the default slot assignments can be changed by modifying the parameter file prior to program execution. This should only be done under the supervision of beam line personnel.