Non-random numbers (SIMH PDP-8)? - test-drb@ccmp.vtda.org

11 Jan 2006

...
  I was playing blackjack (BASIC program) on SIMH with
my OS/8 RL02 image. I
...
  noticed that every time I played the game the cards
drawn were identical,
...
  both by the dealer and myself! A loop to print RND(0)
ten times always
 shows the same ten numbers... doesn't sound very random to me :)

 Is this an artifact of SIMH, or BASIC? (Will it go away when I run the
 program on the real 8/A)?
 In fact many high level languages (and even implementations of hardware
design languages such as Verilog) frequently support the concept of a
repeatable series of pseudo-random numbers to aid in debugging with a
switch to randomise the seed.
Bob