HP-71B CMT RAM module question


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?




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.


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.


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.


Hi Jean-François,

I have an HHP RAM module card reader port.

...and you have mail :-)




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



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


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


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?



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