>1,000 instructions per second times 20 to 30 million times faster is >20 to 30 GHz for a modern laptop? They got an extra zero in there.
Not sure where that came from. The Baby replica actually does about 700 instructions per second. Its a 32 bit serial machine and a bit access time is 10 microseconds. That makes 320 microseconds per store access. There are an extra 4 bit times per cycle to allow the beams on the williams tubes to fly back so that makes 360 milliseconds per store access. Each instruction takes four such cycles making 1.44 milliseconds per instruction. To add two numbers and get the results back into store takes five of these cycles as there is no add. So we load complement to accumulator, subtract, store, load complement, store. That slows us down considerably. In addition no multiply or divide. It tooks the machine 58 minutes to work out the highest factor of 2**18 (which is 2**17). Thats 3480 seconds. Divide that by 10 million gives 384 microseconds. Can a modern laptop do that same calculation in 384 microseconds? I am not sure... Dave ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
