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HP Forum Archive 06

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HP-71B KEYBOARD IS Directive
Message #1 Posted by Vassilis Prevelakis on 25 Sept 2001, 12:33 a.m.

Sorry for posting this again, but I posted it in the wrong thread the first time.


I am trying to find the LEX file that provides the KEYBOARD IS command for the HP-71B. The file in the hpmuseum ftp site ( does not appear to work. It messes up the HP-71B so bad, that only a hard memory lost will fix it (INIT 3).

Does anyone have this LEX file or a procedure that allows external (HP-IL) devices to act as HP-71B keyboard.



Re: HP-71B KEYBOARD IS Directive
Message #2 Posted by Ellis Easley on 4 Oct 2001, 9:02 a.m.,
in response to message #1 by Vassilis Prevelakis

I don't have the answer to your question, but I think you might find some helpful info on Joe Horn's website (the Museum has a link). I know he has indexes of the Swap Disc LEX files by name and function.

I am also interested in using the Swap Disc files. My understanding is that only text files come through the "LIF" scheme intact. From your post, I learned about the Museum FTP site with directories for the Swap Discs. I don't see any explanation there about how to get the binary files (like LEX files) back onto HP-formatted media so they can be used. How did you do it?

Years ago, EduCalc distributed the Swap Discs for the cost of a diskette, I got the first three that way. Also, someone sent me #12 along with a couple of HP75 LEX files that I needed. The printed documentation that EduCalc provided showed a file named KEYBOARD on #3 but it is not on any of my diskettes.

Several years ago I learned someone (maybe Jake Schwartz?) was trying to find a utility to turn the Swap Discs into binary image files that could be distributed and then used to reproduce the Swap Discs. There are several commercial utilities to do this but the people doing the work were looking for something in the public domain. I see that Jake Schwartz's website has on the wish list, adding the Swap Discs to their CD-ROMs, so I guess the search for a PD utility is on-going.

Re: HP-71B KEYBOARD IS Directive
Message #3 Posted by Vassilis Prevelakis on 5 Oct 2001, 11:26 p.m.,
in response to message #2 by Ellis Easley

I finally solved the problem. The data I was loading on the hp71b had nothing to do with the keyboard.lex file.

Let me explain:

The files in the swap disk contain both the directory entry and the actual file. The first 32 bytes of the swap-file is the directory entry, while the rest is the actual file.

I manually separated the directory entry from the file and using the LIF utilities (from the same ftp site), I transfered the actual file onto a floppy disk. (BTW I found that if you use a new PC floppy disk you have to cover the quad density hole - its the hole opposite to the write-protect hole). It is also more reliable to use the hp71b to format the floppy rather than the PC.

I then used the sector editor (again in the LIF utilities disk) to update the directory entry.

This is where I really screwed up, confusing the date field with the field that tells you where the data blocks are stored on the diskette. So when I asked the hp71b to copy file KEYBOARD from the diskette, the directory entry was correct but it loaded some other block from the diskette, thus crushing the hp71b.

Once I figured out the contents of each directory entry, the hp71b was successful in loading the file.

The information at the end of the HP-IL manual for the hp71b was invaluable (just remember the fields are NIBBLES, not bytes :-/ )

So the question is how do you do this tranfer automatically, without the risk of human error. Well these darn disks have 256 byte blocks! Although I did come across a version of the LIF utilites for Linux, they do not work under my Operating System (OpenBSD 2.9).

I'll be experimenting with the RS-232 to HP-IL converter, or with the diskette LIF utils to see if I can get this sorted out.


Re: HP-71B KEYBOARD IS Directive
Message #4 Posted by Ellis Easley on 6 Oct 2001, 3:09 a.m.,
in response to message #3 by Vassilis Prevelakis

Thanks a lot for the info! I haven't used it yet, but you have put me on the right track. I love this kind of thing, I always prefer manual to automatic. My favorite PC program has always been DEBUG - in fact, I think of it as an environment. And I have the HP71 HPIL manual. Don't forget the Joe Horn website for info on the LEX files (especially - maybe exclusively? HP71).

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