DSP1, a Diffractometer Subroutine Package for PDP-8 Computers.
ARMY MATERIALS AND MECHANICS RESEARCH CENTER WATERTOWN MA
Pagination or Media Count:
The AMMRC diffractometer subroutine package, DSP1, was developed to allow a PDP-8 computer with a 4K memory to control a 4-axis X-ray diffractometer in a variety of step scan and integrated intensity measurements in the AMMRC program of materials research. It is used in conjunction with the AMMRC floating point package, FPP1, which it uses for all calculations, input, and output. The general functions of DSP1 include storage and retrieval of scan parameters, conversion of reciprocal space coordinates for cubic systems into shaft angle settings, anti-backlash shaft positioning, and fixed timefixed count X-ray counting with dead time correction, plus bookkeeping and manipulation to repeat measurements for scans with either one 1-D or two 2-D sets of increments. It is composed of 40 subroutines ranging from simple wait loops to complex operations, with the addresses of 31 of these listed on page 0 for easy access, plus a minimal interrupt routine. It also includes a few examples of programs for standard types of measurements. The DSP1 package occupies 978 words of memory, thus, DSP1 and FPP1 together occupy 2079 words, leaving approximately half the 4K memory available for data storage and other programming. As with FPP1, linkages for multiple field operations are left to users with more experience in extended memory systems.
- Computer Programming and Software
- Computer Hardware