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HP-71B CMT Card Reader Memory Module Internal - Printable Version

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HP-71B CMT Card Reader Memory Module Internal - Sylvain Cote - 03-25-2016 04:36 PM

I am currently writing the card reader memory modules section of the HP-71 Compendium
and to my surprise the internal component of the only CMT-CR module that I have was made by HHP.

Are the card reader memory modules sold by CMT was actually made by HHP ?
At this point I assume that my module is either a prototype, a case switch, or whatever.

Can somebody in this forum who has a CMT-CR module can validate who made the internal of his module.
It's pretty easy to verify, just remove the side tape, the module open up in two parts and you can see on the PCB who made it.
If it's HHP, you should see "HHP inc." on one/all of the PCBs, for CMT well I it's for you to tell Wink

Thank you!

Sylvain


RE: HP-71B CMT Card Reader Memory Module Internal - Garth Wilson - 03-25-2016 06:58 PM

I don't find any markings. I have a 96KB CMT module.

[attachment=3292]

[attachment=3293]

I attached two pictures with "Browse..." and "Add Attachment" and clicked "Insert Into Post" but they're not showing up in the preview.


RE: HP-71B CMT Card Reader Memory Module Internal - Sylvain Cote - 03-25-2016 08:05 PM

The pictures are fantastic as they are crystal clear.

So this is very different from the modules internal that I have.
2 HHP and 1 CMT that now I am sure it is a HHP in disguise.

Thank you Garth,

Sylvain

PS: can I use these great pictures in the compendium ?


RE: HP-71B CMT Card Reader Memory Module Internal - Garth Wilson - 03-25-2016 09:35 PM

Sure, you can use them. Here are three more.

[attachment=3295]

[attachment=3296]

[attachment=3297]


RE: HP-71B CMT Card Reader Memory Module Internal - Sylvain Cote - 03-25-2016 09:52 PM

Wow! Something that I did not noticed before.
They seems to have used front port modules to create the card reader ones.
From the manufacturing stand point this is brilliant.
One more case, one more PCB, but everything else is standard.
Thanks for sharing and for allowing me to use these.
Sylvain


RE: HP-71B CMT Card Reader Memory Module Internal - rprosperi - 03-26-2016 12:09 AM

Garth, It appears in the pics that the logo printed on the (RAM?) chip was deliberately scratched/scraped off, though somewehat legible on the middle unit. Does that look true seeing the chips live, or maybe it just appears that way in the photos?

I assume this is a 96KB module, right?


RE: HP-71B CMT Card Reader Memory Module Internal - Sylvain Cote - 03-26-2016 01:01 AM

About HHP 71 M/M modules ...

HHP has created 32KB RAM & EPROM PCB's that they reuse into all their modules.

The 32KB RAM PCB contains ...
-> 1 x HHP designed printed circuit board
-> 1 x HP 1LJ4-0301 custom memory controller chip
-> 4 x Hitachi HM6264LFP-15 8KBytes @ 150 ns

The 32KB EPROM PCB contains ...
-> 1 x HHP designed printed circuit board
-> 1 x HP unmarked custom memory controller chip (probably 1LJ4-0301 as well)
-> 1 x EPROM socket compatible with 27256 (32KB), 27128 (16KB) & 2764 (8KB) EPROM @ 200 ns

HHP 71 M/M 32KB RAM has one RAM board
HHP 71 M/M 64KB RAM has two RAM boards soldered together
HHP 71 M/M 96KB RAM has three RAM boards soldered together
HHP 71 M/M 32KB RAM / 32KB EPROM has one RAM board and one EPROM board soldered together
HHP 71 M/M 32KB EPROM has one EPROM board

Sylvain


RE: HP-71B CMT Card Reader Memory Module Internal - J-F Garnier - 03-31-2016 07:28 PM

My CMT 128kB, same technology with 4 32kB daughter boards.
A backup battery was present, but I removed it.
[attachment=3315]


RE: HP-71B CMT Card Reader Memory Module Internal - Sylvain Cote - 03-31-2016 08:56 PM

Thank you Jean-Fran├žois.
I should have post my question in the main compendium thread.
We now have two threads covering the same informations.
Matthias is posting internal pictures there, we have the rest of the internal pictures here and my comments on both places Sad
Sylvain


RE: HP-71B CMT Card Reader Memory Module Internal - Garth Wilson - 04-01-2016 09:48 AM

(03-26-2016 12:09 AM)rprosperi Wrote:  Garth, It appears in the pics that the logo printed on the (RAM?) chip was deliberately scratched/scraped off, though somewehat legible on the middle unit. Does that look true seeing the chips live, or maybe it just appears that way in the photos?

The one on top is not legible, but the other two are HM62256...

Quote:I assume this is a 96KB module, right?

Yes. I used it for nearly 25 years with absolutely no trouble, and then something happened to it. Now I think it's just that there was some kind of configuration problem, and it might be fine if I just put it back together and put it back in. It had a lithium battery which I removed, not needing it to keep memory outside the 71 anyway, and not wanting the battery to leak. I don't remember if my 32KB front-port memory still has the battery in it or not.

When the FRAM is ready to go (and when the house quits needing repairs so I can afford the FRAM), I would like to get that. I use my 41cx every day though, whereas I seldom use my 71B's.


RE: HP-71B CMT Card Reader Memory Module Internal - rprosperi - 04-01-2016 02:15 PM

(04-01-2016 09:48 AM)Garth Wilson Wrote:  When the FRAM is ready to go (and when the house quits needing repairs so I can afford the FRAM), I would like to get that. I use my 41cx every day though, whereas I seldom use my 71B's.

Good choice, you will not regret getting a FRAM upgrade. Among many other benefits, it basically lets you use any/all the 71 s/w you ever wanted to. And like any of these old machines (as was also true back when we got them originally) it takes a while to transition and feel comfortable but in a little while, it will feel natural again. For the 71B, definitely add the RPN program (the .BIN file, not the .LEX) so number crunching is intuitive.

After 30+ years of the 41, you will need to retrain your finger's memory, but with Forth and Basic and lots of speed, it will quickly justify the transition time.


RE: HP-71B CMT Card Reader Memory Module Internal - Dave Frederickson - 04-01-2016 02:38 PM

(04-01-2016 09:48 AM)Garth Wilson Wrote:  When the FRAM is ready to go (and when the house quits needing repairs so I can afford the FRAM), I would like to get that.

Hi Garth, if you haven't done so already, please add your name to the FRAM71B Pre-Order Poll. By doing so you'll help trigger the production cycle of the updated FRAM71 and there's no obligation to purchase. It just reserves one for you.

By my count, we only need 6 more names. Smile

Dave


RE: HP-71B CMT Card Reader Memory Module Internal - HP-Collection - 04-01-2016 06:18 PM

(04-01-2016 02:38 PM)Dave Frederickson Wrote:  
(04-01-2016 09:48 AM)Garth Wilson Wrote:  When the FRAM is ready to go (and when the house quits needing repairs so I can afford the FRAM), I would like to get that.

Hi Garth, if you haven't done so already, please add your name to the FRAM71B Pre-Order Poll. By doing so you'll help trigger the production cycle of the updated FRAM71 and there's no obligation to purchase. It just reserves one for you.

By my count, we only need 6 more names. Smile

Dave

Dave, why don't you buy 7 items and sell 6 of them through ebay Wink Especially recommented for ultrafast buyers today Wink


RE: HP-71B CMT Card Reader Memory Module Internal - Dave Frederickson - 04-01-2016 06:34 PM

(04-01-2016 06:18 PM)HP-Collection Wrote:  
(04-01-2016 02:38 PM)Dave Frederickson Wrote:  Hi Garth, if you haven't done so already, please add your name to the FRAM71B Pre-Order Poll. By doing so you'll help trigger the production cycle of the updated FRAM71 and there's no obligation to purchase. It just reserves one for you.

By my count, we only need 6 more names. Smile

Dave

Dave, why don't you buy 7 items and sell 6 of them through ebay Wink Especially recommented for ultrafast buyers today Wink

I've already considered that approach: http://hpmuseum.org/forum/thread-5437-post-48425.html#pid48425

Hans has prevented trouble-makers like me from exploiting that loophole. If you read the Pre-Order Poll post carefully you'll see that the list requires 30 names, not interest in 30 modules.

Besides, if there were 6 shoppers on eBay who'd buy a FRAM71, wouldn't their names already be on the list?

Dave


RE: HP-71B CMT Card Reader Memory Module Internal - HP-Collection - 04-01-2016 06:35 PM

(04-01-2016 06:34 PM)Dave Frederickson Wrote:  
(04-01-2016 06:18 PM)HP-Collection Wrote:  Dave, why don't you buy 7 items and sell 6 of them through ebay Wink Especially recommented for ultrafast buyers today Wink

I've already considered that approach: http://hpmuseum.org/forum/thread-5437-post-48425.html#pid48425

Hans has prevented trouble-makers like me from exploiting that loophole. If you read the Pre-Order Poll post carefully you'll see that the list requires 30 names, not interest in 30 modules.

Besides, if there were 6 shoppers on eBay who'd buy a FRAM71, wouldn't their names already be on the list?

Dave

Shure. Maybe it makes sence for Hans to sell some FRAMs on Ebay, too?


RE: HP-71B CMT Card Reader Memory Module Internal - Howard Owen - 04-04-2016 02:59 AM

I tried to talk my Mom into signing up for an account and saying she wanted five but she kept asking why she would want a 21st century update to a retro 1980s computer. It didn't work with her but perhaps some of you may have relatives that are more pliant?

`(April Fool's) +=2


RE: HP-71B CMT Card Reader Memory Module Internal - HP-Collection - 04-04-2016 08:16 AM

So this could be a real question to you, Hans: Do you allow buing more than one item to resell them? This would speed up the time for all of us you and you would get the money anyway. I guess there are HP collectors / users that do not read this forum but have a look at ebay.....

Matthias


RE: HP-71B CMT Card Reader Memory Module Internal - Garth Wilson - 04-04-2016 08:31 AM

Is the problem the set-up costs for getting the PCB(s) made? PCB prices are coming down and down, while at the same time quality is becoming more dependable. Take a look at http://www.dirtypcbs.com/, http://pcbshopper.com/, and http://www.pcbway.com/ . For example, you can get ten 2-layer 5x5cm PCBs for $14 for the lot. "BitWise" on the 6502.org forum says he has used them and the quality seems good and he has not had any problems.