From: tnp@invalid.invalid   
      
   On 30/08/2024 20:50, mm0fmf wrote:   
   > On 30/08/2024 15:45, The Natural Philosopher wrote:   
   >> On 30/08/2024 15:39, mm0fmf wrote:   
   >>> On 30/08/2024 14:28, John Aldridge wrote:   
   >>>> In article <20240829191334.570e88c7507598ffe5b28d87@eircom.net>,   
   >>>> steveo@eircom.net says...   
   >>>>>>>     Portable code should only rely on the standards not   
   >>>>>>> implementations, some very weird possibilities are legal within the   
   >>>>>>> standard.   
   >>>>>>   
   >>>>>> Heh, yes. I worked for several years on a machine where a null   
   >>>>>> pointer   
   >>>>>> wasn't all bits zero, and where char* was a different size to any   
   >>>>>> other   
   >>>>>> pointer.   
   >>>>>   
   >>>>>     That rings vague bells, what was it ?   
   >>>>   
   >>>> Prime. It was word, not byte, addressed, so a char* had to be bigger.   
   >>>>   
   >>> I used a Prime750 at Uni. But only undergrad tasks in Prime BASIC and   
   >>> some Fortran. It seemed quite fast at the time in timeshare mode with   
   >>> plenty of undergrads using it. But the CPU was only as fast as an   
   >>> 8MHz 68000!   
   >>>   
   >> That is the staggering thing. CPU performance in the mini era wasn't   
   >> that hot at all.   
   >>   
   >> I see someone has made a Pi PICO emulate a range of 6502 based   
   >> computers - apple II etc.   
   >>   
   >> I am fairly sure a PI Zero could outperform a 386 running SCO   
   >> Unix...and that was pretty comparable with - if not better than - a   
   >> PDP 11.   
   >>   
   >>   
   >   
   > The CPUs may not have had stunning performance but were generally quite   
   > a bit quicker than the Z80/6502s of the day. The real performance came   
   > from having disks and ISTR hardware assisted IO. i.e. the CPU didn't   
   > have to poll or handle IRQs from each UART but there was something   
   > helping. It's all so long ago now I forget the details. What I do   
   > remember was it was around 1985 when someone lit the blue touch paper   
   > and the performance of micros started rocketing.   Though if you started   
   > 10 years before me there will have been something that was when   
   > performance took off for you. I think everyone has some point in their   
   > memory when things started to go whoosh!   
   >   
   > In 1989 I was writing Z80 assembler to control medical gear. All the   
   > code took about 45mins to cross assemble and link on a Unix system   
   > running on a Vax 11/730. In 1990 we got a 25MHz 80386 running DOS and   
   > the same source took under 3mins to cross assemble and link.  The   
   > bottleneck went from the time to build the code to the time to erase,   
   > download and burn the EPROMS.   
   >   
   Yes. I was writing C and assembler for a 6809 cross complied on a PDP/11.   
   We had PCS as serial terminals and text editors.   
      
   Compile was very slow compared to on a PC.   
      
   The thing was that until the 386 Intel CPUs didn't have the big boy   
   features.  After that they did.   
      
   Even an old IBM mainframe could be emulated under AIX on a PC.   
   I did some work on a Vax running Unix too. Better, but still pretty awful   
      
   --   
   I would rather have questions that cannot be answered...   
   ...than to have answers that cannot be questioned   
      
   Richard Feynman   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)