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Recently I acquired this: ( has not arrived yet):


Unfortunately it comes without manual.
Does anybody know any datails about that box, or even has got the manual?
Please help!
Probably the serial interface part is compatible with HP 82164A.
But what about the LCD-row? Did they implement a video interface ( HP 82163a compatible? ) like CMT did at their "Multi-Case"?
Hopefully a former Oregon Digital employee reads that.
Well, at the moment I don't even know if the device is still working.
Meanwhile the case arrived, and there are evenmore questions.
I will have to replace the old corroded batteries. At first sight I had no idea how these batteries were charged, because there is only one connector (D SUB 15 pin, male, game port type ).
That connector seems to be a all-in-one-solution, what can be seen from the two plugs that came with the device:
The left one is for establishing a serial data link, the right one seems to provide a connector for an AC/DC adapter. I have to find out the polarity. Since there are five cells, giving 6V, would a 8V charger be the best choice?
Interestingly the HP IL signals are ducted outside the case also.
The seller told me that the case was used for surveying tasks; it had been connected to an instrument called Regelta (Carl Zeiss), a tachymeter. Maybe this case was custom-built by Oregon Digital?


What could be the task of that add-on board connected by a ribbon cable?
These two oval objects coated in kind of black shrinking hose, connected by a black and red wire - are additional batteries? Sorry for stupid questions, I don't understand much about electronics.

I really would appreciate any comments, tips and help.
Maybe somebody knows someone who knows an engineer who worked for Oregon Digital? :-)
For example the pin asignment of the connector is of great interest ( in order to use the serial interface - provided that it is compatible with HP 82164a, if not - well, I would need the MANUAL! ).
Sorry, but insertion of the attachments did not work. I am going to try again:
You could ask Mark Olson who was the EE at Oregon Digital in the 1980's.
The item in the 4th photo looks like it plugs into the card reader port.
(05-08-2014 03:57 AM)Dave Frederickson Wrote: [ -> ]The item in the 4th photo looks like it plugs into the card reader port.

Definitively yes! We can recognize the 1LQ4 chip used in HHP RAM/EPROM card reader modules to interface the HP71 bus to standard memory chips. Just close to the 1LQ4 is a 32kB RAM.
My guess is that the ribbon cable extends the HP71 bus to the main board; on it we can see a 27C256 EPROM marked as ODS (Oregon Digital Survey?) that probably holds the software for the HP71.
So you may have 32kB RAM, 32kB EPROM accessible to the HP71, and maybe more (there is something close to the EPROM that looks as an other memory board for the HP71)...

Very nice finding! I would love to find one and study it more.

(05-08-2014 02:35 AM)Sylvain Cote Wrote: [ -> ]You could ask Mark Olson who was the EE at Oregon Digital in the 1980's.
Does Mark Olson have an account here?

Thank you Dave and J-F! Of course, it's a plug for the card reader port!
Once I have replaced the batteries I will see the additional memory and rom, hopefully.
If I won't get further with it, I'll send it to you, J-F!
This unit is a model 7100ED from the photo. Here is a 7100-R SerialPlus. There are obvious differences, but the model numbers are similar. Perhaps the SerialPlus manual that's in the mail will be of some help.

(05-08-2014 12:05 PM)Michael Fehlhammer Wrote: [ -> ]
(05-08-2014 02:35 AM)Sylvain Cote Wrote: [ -> ]You could ask Mark Olson who was the EE at Oregon Digital in the 1980's.
Does Mark Olson have an account here?

No, but you can ask your questions through LinkedIn and see what happens.
What I have found out so far:
Thanks to Dave I got a manual for a similar machine of Oregon Digital, s simpler version called "SerialPlus".
This might help when building a customized serial cable, for example ( because the pinout of the special 15 pin D SUB connector is described there, it it probably was not changed ).
In contrast to CMT's muticase, for example, the serial port and the LCD are not implemented as HP IL devices, therefore I need not plug in the IL cables to get the LCD alive ( see pictures ). The connection is made through the card reader port. For the serial port to work ( according to the manual for the simpler version without LCD, RAM and ROM ) special drivers are neccessary.
Probably special drivers are needed as well for this version, at least it wants to load something from somewhere immediately after being switched on.
I could find out that the device is equipped with 128 K of RAM (!), organized in 4 Ports (5.01 ... 5.04 ) of 32 K each. Port 5.02 cannot be freed, it is always part of main memory. Port 5 (5.00 ) hosts a 32k ROM.

Unfortunately I have big trouble with the power supply: Immediately after the pictures were taken, the calculator went off (shortly displaying a low battery warning ).
I had replaced the 5 NiCd cells by NIMH cells, which in many cases works and is even recommended.
The OD case seems to have emptied these precharged cells quickly.
Now I try to run the device from the power adapter plugged in, but mostly it doesn't respond at all.
Sometimes, after pressing and holding the ON key for a while, it shows the pictured "Welcome screen" on the additional 2-rows display.
Interestingly, the init-sequence ON / works reliably, but immediately after initializing the calculator shuts down.
I should have mentioned that the calculator is powered by the case ( via card reader port ) only, the batteries have been removed, as it is demanded in the manual.
If I only understood a little about electronics ... doesn't it sound as if there was some short curcuit on the OD board?

I put back batteries into the 71b ( although the calculator should be powered by the OD case batteries while connected to it via card reader port, but as mentioned before, that's not enough ).
Now the calculator works reliably - I didn't realize that before because of contacting problems with the membrane keyboard. Just the ON/ATTN key is lower than the f-key next to it, this causes some difficulties in hitting the right key, sometimes I inadvertently switched off ( f ON ).
No I could examine the system a little further:
On startup obviously the built-in ROM takes over and starts the Menu program ( see pics at last post).
Maybe there is a way to prevent that and disable auto start, by setting a system flag or something, I don't know.
So I have to break the running program to get to normal HP 71b operation.

Any idea of a HP 71b expert of a more elegant solution?

Listing of the menu program shows that the two-rows LCD is written to by a new keyword: XDISP.
Also fine: In contrast to the simpler version "OD Serialplus" this case already has available the serial drivers (BASIC keywords: SETUP and SERIAL$ ) in ROM, no additional software is needed.
Confirmed: all RAM ports ( 5.01 up to 5.04 ) can be freed and claimed, except 5.02 ( always claimed, means: part of main memory ). Somewhat strange, isn't it?
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