HP-71B ROM versions


I have a 71B and I have been reading and seeing references to the ROM versions on this machine. What I keep seeing is ROM version 1BBBB.

My 71B returns a ROM version 2CDCC. Seems like a big jump to me in ROM versions?

Some history. I picked this machine up at a ham-fest. It is a late '89 model. The hpdata base says that the 71B was discontinued in '88. But the museum here says '89.

What I am wondering here is if HP had a contract that they had to complete after they stopped selling to consumers?? Just a guess. Also I'm poking in the dark here. Maybe these units were some kind of special unit that the contract required. What are the differences?

If anybody knows some history of this machine I'd appreciate some more info on the ROM versions for the 71B



As a HP-71 "expert" I feel, it's my duty to answer that.

2CDCC was the last version. I also believe, they ended the production of the 71B in 1988, but the machine was much longer on the Austrian pricelist, that in a lot of other countries. The reason seems to be, that a large insurance company in Austria ("Sparkasse Versicherung") had ordered and bought about 1000, or even more machines from HP over a long-time contract. This contract had to be fulfilled and that was the reason, that the 71B was kept as a "machine in production". Sparkasse was HPs 2nd largest contractor workdwide buying the 71Bs

There seemed to be a similar case in the U.S., where the U.S. army (and possibly other contractors) had such agreements. The U.S. army used the 71Bs for control of their M-110 cannons. (The U.S. army was the largest contractor).

AFAIK 2CCCC had a major bug in redimensioning arrays while running a program (I don't own such a machine, so I don't can check this) and HP had to correct this.

1BBBB was the first public revision and it remained stable for a long long time (I own the IDS for this version). There was also an IDS for the 2CDCC version, but I don't know anybody, who owns it.

I have a pre-production version of the HP-71B in my posession (Serial 0000A00022)

The Ver$ string returns: "TI%RM4-HP71:0AAAA"


I think that this unit might have come from the goverment sale. The person who was selling them had a pile of them. Just the computer with the case in what looked like unused condition, and a photocopy of the QRG.

One question. If 1BBBB was stable for so long why did they change the ROM? Did they add some new functionality?

Thanks for the info Reinhard very much appreciated,



1BBBB was stable, but not free of errors. It seems, that there were some commercial customers, who wanted some bugs get fixed.
The Bugs were not very serious and you had to construct them (mostly).

Much of them were small problems with the UDFs (User Defined Functions). I remember a 1 and a half page list with Errors in the 1BBBB version. I'd guess it was in a PPC or CHHU journal.

There was definitely no new function implemented.


Thanks for all the great information Reinhard !


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