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Re: OKAD?

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On 9/14/2016 4:02 PM, Jan Coombs wrote:
> On Wed, 14 Sep 2016 13:18:48 -0400
> rickman <gnuarm@gmail.com> wrote:
>
>> On 9/14/2016 6:33 AM, Jan Coombs wrote:
>>> On Wed, 14 Sep 2016 05:55:20 -0400
>>> rickman <gnuarm@gmail.com> wrote:
>>>
>>>> On 9/14/2016 5:33 AM, Jan Coombs wrote:
>>>>> On Wed, 14 Sep 2016 05:08:52 -0400
>>>>> rickman <gnuarm@gmail.com> wrote:
>>>>>
>>>>>> Some people insist in referring to the delay line
>>>>>> technique as a "ring oscillator".
>>>>>
>>>>> Maybe Chucks ring oscillator has both taps and gating, and
>>>>> is the only delay element in each processor core?
>>>>
>>>> Except that it doesn't oscillate.  When the CPU is waiting
>>>> it stops.
>>>
>>> If you have gates in the ring oscillator loop you can pause
>>> or stop the clock at any phase.
>>>
>>> Chuck must have at least one gate to be able to pause it.
>>
>> I don't get why you feel it has to be a "ring oscillator".
>> There are many different timings each one adjusted to match
>> the circuit it is timing.
>
> I like your ASCIIart, but cannot quickly see how it affects the
> operation cycle of a S40C18 or similar processor.
>
> Perhaps we should build a model in HDL with realistic gate
> delays and see if we can guess any closer, or even reproduce
> the instruction timing as in the data sheet.
>
> I think that it might be possible to model asynchronous logic on
> ProASIC3 and similar parts, so the library components for these
> might be a practical starting point if we hoped to reproduce
> anything close to Chuck's work.

If that diagram does not mean anything to you, we are mis-communicating 
at a fundamental level and coding would not help.

I have not read about the processor in the S40C18 in any detail, but it 
appears similar to the processor in the GA144.  I believe the diagram 
you snipped is a useful block diagram of the functionality.  I know that 
processor has different instruction timing for different categories of 
instructions.  That is why I show different timing circuits.  The 
control circuit selects a delay circuit based on the opcode being 
executed.  Some instructions are simple, requiring a minimum delay.  But 
with multiple instructions per instruction word, there is a timer for 
the next instruction word prefetch.  If a branch occurs in the 
instruction word a different timer must be selected.  If a memory 
instruction is executed a different timer is selected.  If an I/O 
instruction is executed a different timer is selected and control may 
also depend on a signal back from the I/O unit.  The processor is 
typically stopped until the I/O operation is complete which requires a 
response from the neighbor.

I get the impression you are thinking of other types of asynchronous 
logic where the timing information is contained within the data path 
itself.  I am pretty sure that is not how the GA144 operates, but I 
can't say for certain of course.

-- 

Rick C

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OKAD? Mux <Yvo.Zoer@gmail.com> - 2016-08-22 15:07 -0700
  Re: OKAD? Paul Rubin <no.email@nospam.invalid> - 2016-08-22 15:31 -0700
  Re: OKAD? Bernd Linsel <bl1@gmx.com> - 2016-08-23 01:45 +0200
    Re: OKAD? Mux <Yvo.Zoer@gmail.com> - 2016-08-23 13:55 -0700
  Re: OKAD? JUERGEN <epldfpga@aol.com> - 2016-09-09 00:18 -0700
    Re: OKAD? JUERGEN <epldfpga@aol.com> - 2016-09-09 02:47 -0700
      Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-09 11:52 -0400
        Re: OKAD? JUERGEN <epldfpga@aol.com> - 2016-09-09 10:22 -0700
        Re: OKAD? Mark Wills <markwills1970@gmail.com> - 2016-09-09 14:57 -0700
          Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-09 18:02 -0400
            Re: OKAD? Paul Rubin <no.email@nospam.invalid> - 2016-09-09 15:33 -0700
              Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-10 01:55 -0400
              Re: OKAD? mhx@iae.nl - 2016-09-09 23:36 -0700
                Re: OKAD? Jecel <jecel@merlintec.com> - 2016-09-12 13:48 -0700
                Re: OKAD? Paul Rubin <no.email@nospam.invalid> - 2016-09-12 14:17 -0700
                Re: OKAD? Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-09-13 00:01 +0100
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-13 14:54 -0400
                Re: OKAD? Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-09-14 08:50 +0100
                Re: OKAD? Paul Rubin <no.email@nospam.invalid> - 2016-09-14 01:15 -0700
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-14 05:08 -0400
                Re: OKAD? Paul Rubin <no.email@nospam.invalid> - 2016-09-14 02:14 -0700
                Re: OKAD? Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-09-14 10:33 +0100
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-14 05:55 -0400
                Re: OKAD? Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-09-14 11:33 +0100
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-14 13:18 -0400
                Re: OKAD? Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-09-14 21:02 +0100
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-14 17:20 -0400
                Re: OKAD? Jecel <jecel@merlintec.com> - 2016-09-15 10:54 -0700
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-15 17:28 -0400
                Re: OKAD? Jecel <jecel@merlintec.com> - 2016-09-16 10:38 -0700
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-17 17:05 -0400
                Re: OKAD? Jecel <jecel@merlintec.com> - 2016-09-21 13:42 -0700
                Re: OKAD? rickman <gnuarm@gmail.com> - 2016-09-21 18:03 -0400
                Re: OKAD? Jecel <jecel@merlintec.com> - 2016-09-23 13:21 -0700
    Re: OKAD? albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-09 14:01 +0200
      Re: OKAD? JUERGEN <epldfpga@aol.com> - 2016-09-09 04:57 -0700
  Re: OKAD? Ilya Tarasov <ilya74.tarasov@gmail.com> - 2016-09-13 09:18 -0700
    Re: OKAD? JUERGEN <epldfpga@aol.com> - 2016-09-13 10:09 -0700
      Re: OKAD? Ilya Tarasov <ilya74.tarasov@gmail.com> - 2016-09-16 17:24 -0700
        Re: OKAD? JUERGEN <epldfpga@aol.com> - 2016-09-17 02:38 -0700

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