Implementing a Pseudorandom Number Generator on a Minicomputer

Three contemporary pseudorandom number generators: Tausworthe, GFSR, and Lehmer are implemented on a 16-bit minicomputer. Practical comparisons are made in terms of 1) ease of implementation, 2) length of period, 3) execution speed, 4) program storage space, and 5) statistical quality. Although the results are conjectured to apply to any 16-bit word, limited memory capacity, and limited instruction set computer, the results for a PDP-11/05 indicate that the Lehmer generator satisfies criterion 5) but is slow and difficult to implement. The GFSR generator satisfies criteria 2) and 3) but is large, and the Tausworthe generator satisfies criteria 1) and 4) but can be statistically marginal.