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Re: GA144 Instruction Timing

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On 8/11/2012 6:54 PM, rickman wrote:
> Anyone know the timing of a unext instruction when it is looping? I
> think it would just be 2.4 ns with no adder for the instruction fetch
> since there would be no instruction fetch.
>
> The data book talks about the "Empty micronext time" which seems to be
> the time for the unext instruction with no other code in the loop
> regardless of whether it loops or not. They also talk about an empty
> next time, but this is separate from the "non-empty next time" along
> with "jump time". I guess the time for the jump if the code falls
> through would be the same if it aborts the prefetch in all cases even if
> it could take advantage of prefetch.
>
> Funny, every time I look at this chip I learn something new about how it
> works. It would be nice if it were written out clearly enough that I
> didn't need so many passes through the manual.
>
> At least I feel like I am getting somewhere with it.
>
> Rick


I got what I think is the final reply from GreenArrays.  I asked for 
timing data that is not currently available in the data sheets and the 
response was, "there won't be a new model any time soon".

I suppose that if you consider the GA144 to be a software device then 
timing is not really important.  Lots of high end CPUs are not very 
deterministic.  But if you want to use it to control hardware with any 
speed or precision you will find it difficult, at least if you want to 
use the design methods you are used to, data sheet timing data, 
simulator timing results, static timing analysis.  Instead you will need 
to buy an eval board, take your own measurements, then correct them for 
process, temperature and power supply voltage variations.

I've got paying work at the moment so I don't have any more time to play 
with the GA144.  But I may come back to this in a couple of months.  I 
still like the idea of a single chip (plus memory) oscilloscope.  I bet 
it can do the best job of any CPU at that task... if you have the 
stomach for dealing with such an odd chip.

Rick

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GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-11 18:54 -0400
  Re: GA144 Instruction Timing Paul Rubin <no.email@nospam.invalid> - 2012-08-11 17:40 -0700
    Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-12 19:00 -0400
      Re: GA144 Instruction Timing johnmdrake@gmail.com - 2012-08-14 10:17 -0700
        Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-15 18:57 -0400
  Re: GA144 Instruction Timing RR <freedomspyder@gmail.com> - 2012-08-22 07:11 -0700
    Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-22 10:33 -0400
      Re: GA144 Instruction Timing RR <freedomspyder@gmail.com> - 2012-08-22 12:46 -0700
        Re: GA144 Instruction Timing Jason Damisch <jasondamisch@yahoo.com> - 2012-08-22 13:10 -0700
          Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-22 18:10 -0400
          Re: GA144 Instruction Timing Paul Rubin <no.email@nospam.invalid> - 2012-08-23 00:03 -0700
            Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-23 19:57 -0400
              Re: GA144 Instruction Timing Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-24 16:29 +0200
                Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-27 18:33 -0400
                Re: GA144 Instruction Timing Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-28 02:45 +0200
                Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-27 21:41 -0400
                Re: GA144 Instruction Timing Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-28 22:07 +0200
                Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-28 18:25 -0400
                Re: GA144 Instruction Timing Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-29 01:41 +0200
                Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-29 16:43 -0400
                Re: GA144 Instruction Timing Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-30 02:13 +0200
                Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-30 15:07 -0400
                Re: GA144 Instruction Timing Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-30 23:11 +0200
                Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-09-01 15:15 -0400
        Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-08-22 18:05 -0400
          Re: GA144 Instruction Timing RR <freedomspyder@gmail.com> - 2012-08-22 15:46 -0700
  Re: GA144 Instruction Timing rickman <gnuarm@gmail.com> - 2012-09-02 17:21 -0400

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