2002-11-19 Oh, another thing. I remember back in the early 1980s, problems with CNCs and numbers. The problem was visible whether the CNC was in the inch (G70) mode or the millimetre (G71) mode. When data was manually entered, it was common for last digit to flicker on the display. For example, if the number 10.000 was entered, the display would flicker between 9.9999 and 10.001. This was due to the "conversion" error when the input was converted to binary from decimal and back to decimal again to be displayed. It was due entirely to the 8 bit accuracy of the machines. I'm sure now a days, with 32 bit accuracy, and the display being a monitor and not an LED or Nixie tube, plus a million more improvements, this does not happen.
I'm sure a lot of those old CNC's from that era are still in use. Is this person confusing the technology to handle decimal to binary conversions and vice versa of 20 years ago with today? What does this mean? This sounds like gibberish to me. furthermore the problem worsened as the time element entered the equations, and as the frequency of 12 and 24 increased. Microsoft knew at that time the metric system of measurement had to go........... And what was the "metric system" replaced with? Who is WE? What real numbers associated with the metric system? Is this person trying to tell someone that there will be a problem expressing 35 mm, but no problem expressing 35 inches? Am I understanding this person's logic correctly? What is he getting at? We are convince that engineering data exchange under ISO10303 will be problematic and will emanate from the extensive use of real numbers that are associated with the metric system of measurement John ----- Original Message ----- From: <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Tuesday, 2002-11-19 13:51 Subject: [USMA:23500] (fwd) Re: Can the metric system work? I've had the following enquiry, and would appreciate comments from anyone more knowledgable in this sphere than myself! (In the meantime, I'll try to understand his problem better.) Chris >We have experienced a great deal of system crashes and a high degree of >inaccuracies associated with all CNC software. We decided to involve >Topology and Automata experts to assist us in overcoming the problems. The >outcome was that the software data sets during the conversion from Hex to >Deci (ADI system) were the prime cause in that rounding off became >impossible for math coprocessors to handle at 1st level maths. For accurate >CNC operations we would require 4th level maths. It was later brought to our >attention that Microsoft was aware of this problem during the 1992 Alpha >Tests at which time it became abundantly clear that the problem could not be >rectified, furthermore the problem worsened as the time element entered the >equations, and as the frequency of 12 and 24 increased. Microsoft knew at >that time the metric system of measurement had to go and that Hex and Deci >will never mix. We are convince that engineering data exchange under ISO >10303 will be problematic and will emanate from the extensive use of real >numbers that are associated with the metric system of measurement. >Kindest regards, > >C H. Ryton. > >----- Original Message ----- >From: <[EMAIL PROTECTED]> >To: "Carlisle H. Ryton" <[EMAIL PROTECTED]> >Sent: Sunday, November 17, 2002 10:13 PM >Subject: Re: Can the metric system work? > > >On Sun, 17 Nov 2002 15:28:37 -0000, you wrote: > >>Can you tell us how the metric system works with a 64 bit integer math and >binary algorithms setup? >> >>Regards, >> >>C H. Ryton. -- UK Metric Association: http://www.metric.org.uk/
