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Full Version: HEPAX and CCD - Conflict of Interest?
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Hi, I have a CX halvenut with a Hepax (1D) and a CCD (B) as I love the direct access to System registers via CCD yet I'm alos playing with m-code.

However the Hepax has the annoying tendency to simply dissapear from Cat 2 every so often. Unplugging it and replugging it into different slots, unplugging CCD etc eventually brings it back (with memroy lost naturally, how convenient, 'Goto "Key in 500 m-codes again", do not go over start, do not collect 200'...).

I wonder if there are any incompatibilities with the CCD that cause this to happen. I read that the early/beta versions of the HEPAX had some internal problems yet I thought by version 1d that should have been resolved...

Anyone any thoughts? Thanks so much in advance!



The clonix NoVram Hepax module does not lose it's contents when unplugged.

You might even make money selling the Hepax and buying a NoVram module.

Hi Peter,

does the HEPAX disappear completely,

I mean not only from CAT 2,

but regarding it's functionality?

You know that the HEPAX moves itself

to the lowest possible bank,

which often will be bank 6

if the HP-IL module isn't plugged.

Then you'll find the CAT entry *only*

with a CAT 2, not with a CCD CAT'n (n>7)

From my experience, the HEPAX and CCD modules

don't interfere, so there shouldn't be a problem

from the software side.

However, I have to admit that I only used the NoVRAM

emulation of the HEPAX, not the real one.

And in most cases I use the CCD OS/X

instead of the full CCD module;-)

You could also try another approach:

Using the HEPAX (or a NoVRAM) along with the CCD OS/X.

The CCD OS/X includes all system extensions of the CCD module,

except for the extended CAT'4.

This feature will be added in the bank switched version.

Another complication could happen if you plug

in the HEPAX without the CCD module in place,

and then have the HEPAX assign IDs to it's

RAM pages.
There's still a chance that these new IDs

interfere with ones from another plug-in module,

like the CCD.

And of course the general tip:

The one who laughs in the end - has a backup;-)



I think Raymond's last observation is the issue: if you plug in the CCD *after* the HEPAX has been previously initialized, then it is more that likely that the XROM ID's assigned to the HEPAX RAM would conflict with those of the CCD (i.e. 9 and 11).

This is trivial to correct: using HEXEDIT change the first word of those RAM pages to non-conflicting id's


Thanks guys, I'll try all those things out. As for some of the questions raised:
1) HEPAX disapears completely, not only from Cat2
2) I have a test running right now where I recorded (to makes ure) the sequence of putting the modules in.

The strange thing is that it works for a while all fine and then suddenly disapears.

As I was programming my own rom, one issue could be that I used the wrong XROM numbers (despite trying to pick a free one...)

Anyway, I'll apreciate all the info and let you guys know how it goes.

Ah, one more question - Raymond mentioned this one thing, that makes one laugh, what was it? - called reversehigh, Rueckenauf, ah, no: backup! That's it. What kind of advanced technology is that???


Thanks to all involved I was able to fix the issue it seems. And Osram's razor stroke again - the contacts were dirty and caused the "wackelcontakt". Some alcohol and TLC fixed it, to my utter delight!

Thanks again for all your infos, I also learned something about the right sequence of plugging those things in!