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HP Forum Archive 18

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Problem: 2nd 32k of CY suddenly missing
Message #1 Posted by PeterP on 5 June 2008, 12:28 p.m.

Hi,

Yesterday I wanted to load some code into my CY's internal rambox and realized that the 2nd set of pages seems not to work. Oh Schreck o Graus!!!

Basically, it seems that the command PG<> does not switch the pages and I always see the same set. Cat 2 shows Rambox 64a both times. I also copied a 4k rom into the F page and it shows up even when I do a PG<>. Also, after a PG<> the calc does not respond for a little while before being back on-line.

Has anyone ever seen such a behavior? Any ideas on how to fix this or could it be a hardware failure (which is hard for me to imagine given that it is treated very well and rests most of time, with the regular battery check-up and usage).

Thanks so much for your kind help!

Cheers

Peter

      
Re: Problem: 2nd 32k of CY suddenly missing
Message #2 Posted by Raymond Del Tondo on 5 June 2008, 1:53 p.m.,
in response to message #1 by PeterP

Hi Peter,

the RAMBox OS of the 2nd bank got erased somehow, not more, not less.
Usually happens if the backup battery is near to flat while changing main batteries.
Another cause could be some ML routine gone wild, while the WP switch was in the wrong position...
Apart from that, it's relatively unlikely (but not impossible) that there's a loose contact on the W&W pcb.

The software related matters can be fixed and reloaded with my INIT module for the CY within a few seconds;-)

HTH

raymond

            
Re: Problem: 2nd 32k of CY suddenly missing
Message #3 Posted by PeterP on 6 June 2008, 11:05 p.m.,
in response to message #2 by Raymond Del Tondo

hmm,

Well, this is what I first thought as well, and given that there is some good and detailed info here on the forum and I have all the necessary ingredients (HP-IL card, various MCODE moduls, etc) I thought it would be rectifyable and a fnu adventure. But the behavior of that CY is a bit more intricate...

Here are the steps that I took and the result. If anyone can make heads or tails of this, I will be all ear!

  1. The start-configuration is a working configuration, with WWOS a in page 8 and all pages visible and usable. This is the first 32k (Block a)
  2. I then put a Clonix with the ML rom mapped to Page F in
  3. Via HP-IL/Emu41 I copied a WWOSa into page 9
  4. Then I did a PG01 which activated pages 9,11,13,15 from the second 32k (Block b)
  5. Via HP-IL/EMU41 I copied a WWOSb into page 9
  6. Now I put in a Games module in Port one to mask page 8
  7. I confirmed that PG01 has the WWOSb in page 9 and PG10 has the WWOSa in page 9
  8. I now replaced the Clonix with a Zenrom so that I have a Rameditor available.
  9. I then copied a 4k module (XIO) into all pages in both configurations. At that point, we had OSa in page 9 for Block a and OSb in page 9 for Block b, XIO in page 10,11,12,13,14 (presumambly for both blocks but, as we shall see shortly, not so much) and the Zenrom on page 15
  10. I now did a PG01 to have 10/12/14 from Block a and 9/11/13 from Block b
  11. using MCED from the Zenrom, I now changed the word xFFB/xFFC in all pages, namely 10,11,12,13,14 and confirmed that the changes actually took place
  12. now I did a PG10. My expectation was that I will have OSa in page 9 and XIO in all other pages, but unaltered at xFFB/xFFC
  13. well, not so much. As it turns out, this assumption is correct for 11 & 13, but not for 10,12,14!!!
  14. so it would appear that the odd pages are switchable (9/11/13) but there is only one set of even pages visible (10/12/14)

This is truly odd, as I can not imagine any HW defect that would cause this.

The one thing that gives me hope is the odd behavior whenever I do a PG10 (or the second PG<>) - the calc goes into a strange mode and is recovered after a short while or a Enter/On. This seems like some odd code in the polling area of one of the pages.

I read all the threads that can be found here and they show quite a few tips and tricks on how to successfully recover the OS for the CY. If the OS on one Block were gone, I believe that the above sequence should have restored full access to all pages with the possible exception of page 8 in Block b (as that was always masked). And with the right OS in page 9, and page 8 masked, the Block b should be quite happy and appear and respond normally to PG<> and PG10.

So I can't make sense of this odd behavior. Any thoughts?

Cheers

Peter

                  
Re: Problem: 2nd 32k of CY suddenly missing
Message #4 Posted by Raymond Del Tondo on 6 June 2008, 11:46 p.m.,
in response to message #3 by PeterP

Hi,

it's not too easy to make a clean reset/install of both RAMBox banks, if one of the OSes is gone.
This is why I made my INIT module, the only reliable way to restore the W&W RAMBox OS to both banks;-)

Before making the INIT module, I also spent many hours trying to get the beast going.
However there was one point where I decided to solve this problem once for all times: CY INIT Module:-)

Cheers

Raymond

Edited: 6 June 2008, 11:48 p.m.

                        
Re: Problem: 2nd 32k of CY suddenly missing
Message #5 Posted by PeterP on 6 June 2008, 11:55 p.m.,
in response to message #4 by Raymond Del Tondo

so how do you explain the observed behavior? It is not consistent with the OS missing from one page (see the thread with Werner, you, Mike and Meindert from a few years ago and how it was solved: 

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv014.cgi?read=48617 
http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv013.cgi?read=47293 
http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv014.cgi?read=49179
)

How do you explain the observed behavior?

Cheers

Peter

                              
Re: Problem: 2nd 32k of CY suddenly missing
Message #6 Posted by Raymond Del Tondo on 7 June 2008, 12:18 a.m.,
in response to message #5 by PeterP

Hi Peter,

the 'hide the other ports and copy the OS, then try to switch' method only works if you're lucky, ut it's not reliable.
It's the usual hen-egg problem: You want to switch to a page,
which in return has to respond in an appriorate way.

The observed behaviour of your CY only means OS-b is missing,
and maybe there are some garbled pages somewhere, nothing else.

Cheers

Raymond

                                    
Re: Problem: 2nd 32k of CY suddenly missing
Message #7 Posted by PeterP on 7 June 2008, 3:05 p.m.,
in response to message #6 by Raymond Del Tondo

hmm, unusualy mysterious and non-remedial tone. I thought business ads have a separate section here :-))

Anyone else hears my plea to make heads of this?

I guess I'd better crawl back in my n00b cave...

(Cheers)

Peter

                                    
Was: problem now is: happiness!!
Message #8 Posted by PeterP on 7 June 2008, 8:36 p.m.,
in response to message #6 by Raymond Del Tondo

thanks to a) Raymond's friendly 'heckling', b) a humid heatwave making all of us run for ac shelter inside and c) the tremendous amount of info here my trusty CY is fine again.

I can now understand why RDT said he wanted to solve this 'once and for all'... But long distances and lack of iq and knowledge make this a solution that is only open to select few and most certainly not me:-)

Yet luck, stuborness - sorry, I meant persistence, and many hours can sometimes help. As we say at home - even the blind hen finds a grain once in a while...

Anyway, this happy 'hen' willl now have a celebratory beer! Thanks again raymond, (and werner for his great recovery posts, mike for his great insight into the code differences of the os and jf-g on his crisp and clean article on bankswitching of the cy) would be fun to have you here to share the beer!

Cheers

Peter

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