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HP Forum Archive 18

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HP-71B CMT RAM module question
Message #1 Posted by J-F Garnier on 30 Jan 2008, 2:53 p.m.

Hi, I have a 64k CMT front port RAM module as well as a 128k module in the card-reader slot. The modules are made of 2 and 4 x 32k ports respectively. I think it is possible to configure the modules as 64k ports (1 and 2 ports respectively), but I didn't succeed to locate any information on it.

Is there somebody here who has CMT RAM modules configured as 64k ports, and knows how to do it?

Thanks.

J-F

      
Re: HP-71B CMT RAM module question
Message #2 Posted by Eric Smith on 30 Jan 2008, 5:41 p.m.,
in response to message #1 by J-F Garnier

I have a very vague memory of seeing jumpers for that purpose on the PC boards inside the card reader port memory module. Unfortunately I don't recall the details, and I don't have any documentation on them.

      
Re: HP-71B CMT RAM module question
Message #3 Posted by Rodger Rosenbaum on 30 Jan 2008, 6:23 p.m.,
in response to message #1 by J-F Garnier

I think it can't be done. I remember calling CMT on the phone and asking about this very thing and they said it couldn't be done.

The memory in the CMT Prom burner has a switch to select either 32k or 64k mode, and I think that's the only CMT product that can have a 64k mode.

However, the Hand Held Products memory modules for the cardreader port can be wired for either 64k or 32k mode. I have a 96k module I got on ebay, and it came wired as 3 32k ports, but I was able to move a jumper on the board and re-configure it as one 64k port and one 32k port.

So what you need to do is find a Hand Held Products card reader module.

            
Re: HP-71B CMT RAM module question
Message #4 Posted by Eric Smith on 30 Jan 2008, 6:47 p.m.,
in response to message #3 by Rodger Rosenbaum

Yes, the HHP card reader port RAM module is the one I was thinking of. I used to have the 160KB version, and it was configurable.

      
Re: HP-71B CMT RAM module question
Message #5 Posted by Etienne Victoria on 31 Jan 2008, 4:43 p.m.,
in response to message #1 by J-F Garnier

Hi Jean-François,

I have an HHP RAM module card reader port.

...and you have mail :-)

Cordialement

Etienne

            
Re: HP-71B CMT RAM module question
Message #6 Posted by Raymond Del Tondo on 31 Jan 2008, 4:57 p.m.,
in response to message #5 by Etienne Victoria

Hi Etienne,

I also have an HHP CR port RAM module, and even the original user instructions for it.
But these user instructions don't mention the RAM port size configuration,
only the different types of modules (RAM, EPROM), and that they occupy port 5.
However in these instructions booklet, the biggest RAM module was 96K,
so maybe later versions are more precise, or have more features?

Best Regards

Raymond

                  
Re: HP-71B CMT RAM module question
Message #7 Posted by Etienne Victoria on 1 Feb 2008, 3:04 p.m.,
in response to message #6 by Raymond Del Tondo

Hi Raymond,

Mine is an HHP card reader port 96K Ram.

I have no instructions for it but will try to port configure it when I have time this week-end and update the forum.

Best regards

Etienne

Edited: 1 Feb 2008, 3:04 p.m.

                  
Re: HP-71B CMT RAM module question
Message #8 Posted by Etienne Victoria on 3 Feb 2008, 9:09 a.m.,
in response to message #6 by Raymond Del Tondo

Hi Raymond, all

On the HHP 96K RAM module, all my free port commands result in allocation of 32K Ram blocks which is clearly not what is expected by JF.

I guess proper config must be hardwired.

Before I open the module, does anybody know the mods (jumpers, connections...) that must be performed on it?

Cheers

Etienne


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