开云体育

On Tuesday (04/09/2024 at 05:57PM +0000), Don via groups.io wrote:
> Hi Chuck,
> Thanks for the suggestion. I do have a spare PC that I can install Linux on and I will be acquiring an EPROM burner shortly. However, I have no experience whatsoever with programming so terms like “jump table” and “ data declaration “ go way over my head. I am willing to learn, though. Luckily, Mark (over on Tekscopes) will be collaborating with?me and it sounds like he is planning to do something similar to?what you are proposing. Regardless of the outcome, it will be an interesting and educational experience for me.
>
> Don
> On Tuesday, April 9, 2024, 12:13 PM, Chuck Harris <cfharris@...> wrote:
>
> Hi Don,
>
> It occurs to me that if you have a linux machine, and a eprom
> burner, you could fix your problem by simply creating an
> eprom that has the 6808's jump table, and a two line program
> that copied a data declaration that contained the calibration
> constants into the NVRAM space where the constants belonged.
>
> There are lots of free assemblers in linux land that can create
> 6808 hex code that can be burned into eproms.
>
> Make one, and swap out the eprom that contains the vector table
> with your new vector table and copy program.
>
> -Chuck Harris
>
>
> On Sat, 6 Apr 2024 08:49:49 -0400 "Chuck Harris" <cfharris@...>
> wrote:
> > Hi Don,
> >
> > I'm here, and a few other places too.
> >
> > Typically, losing the calibration data while changing the
> > battery happens when you forget that your soldering/desoldering
> > iron tip is grounded, and you use a backup power supply that is
> > also grounded...? Sounds like you didn't do that.
> >
> > I don't know how to get the data back into a pre 50000
> > 2465B.
> >
> > A long time ago, a retired (or former) tektronix person? told
> > me that it could be done... and indeed, it makes little sense
> > to allow you to read the data and not actually be allowed to
> > change it... I recall verifying that it works, but I don't
> > recall the method anymore.
> >
> > I didn't concentrate on it mostly because I just recalibrate
> > the things, which eliminates the need.
> >
> > I would say that it is long past time for someone to disassemble
> > the ROM code for this beasty.? It is really easy with the 6802
> > processor.
> >
> > There are a bunch of opensource disassemblers available.
> >
> > -Chuck Harris
> >
> >
> > On Fri, 05 Apr 2024 16:08:37 -0700 "Don via groups.io"
> > <donald_s_58103@...> wrote:
> > > Hello all,
> > >
> > > I have posted this on the Tekscopes Forum, but I am posting it here
> > > too in the hopes that Chuck Harris sees this because I have seen a
> > > post of his on the Tekscopes Forum which might solve my problem.
> > >
> > > I had a perfectly functioning 2467B scope (1989 vintage). After
> > > reading about possible loss of calibration data due to the NVRAM
> > > battery dying, I decided to put in a new battery (mine is the older
> > > version, below 50000 serial #) which has the battery separate from
> > > the NVRAM. The battery had a date code of 2689, so the battery is 35
> > > years old. I did hook up a backup battery before removing the
> > > Lithium battery and confirmed that pin 28 of the RAM chip had at
> > > least 3 V on it from the backup battery after removal of the
> > > original battery. After putting in the new replacement battery, I
> > > also changed out the 4 electrolytic capacitors on the A5 board.
> > > When I put the scope back together and fired her up, I got the
> > > dreaded " Test 04 Fail 13" message indicating corrupted or lost
> > > calibration data. Not sure how this happened since I hooked up a
> > > backup battery before removing the original battery. So, the very
> > > thing I was hoping to prevent happened by my being proactive!
> > >
> > > Before doing all this, I had made a copy of the RAM contents by
> > > running through the Exercise 02 option, so I have the original
> > > calibration data available. My question is: how to write this data
> > > to the RAM? (my scope does not have the GPIB option). Chuck Harris
> > > seemed to imply that it would be possible to write the saved
> > > calibration data to the RAM manually.
> > >
> > > I look forward to your suggestions and hope to get this fine scope
> > > functioning again!
> > >
> > >
> > >
> > >
> > >?
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--
Chris Elmquist