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HP Forum Archive 17

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71B questions
Message #1 Posted by Vincze on 19 Aug 2007, 7:33 p.m.

I still looking for 71B very badly. One question I have though is I never see slip case for it. Did it not come with one. Also, I see many time modules for 71B. Where do these modules go? I know on 41C series, there are ports on the north side of unit, but 71B look like big/long 15C.

      
Re: 71B questions
Message #2 Posted by allen on 19 Aug 2007, 7:39 p.m.,
in response to message #1 by Vincze

Quote:
I never see slip case for it.Did it not come with one.

They look like THIS and were included with all new 71b calcs.

Quote:
Where do these modules go?

On the South EDGE . Two on the left, two on the right.

Edited: 19 Aug 2007, 7:40 p.m.

            
Re: 71B questions
Message #3 Posted by Vincze on 19 Aug 2007, 7:50 p.m.,
in response to message #2 by allen

Okay, so case look like 41C case?

What are other covers on bottom of machine?

                  
Re: 71B questions
Message #4 Posted by Maximilian Hohmann on 19 Aug 2007, 8:05 p.m.,
in response to message #3 by Vincze

Hello!

Quote:
Okay, so case look like 41C case?

Yes, very similar, but the size is different (bigger, but less thick).

Quote:
What are other covers on bottom of machine?

The biggest in the middle is the battery door (4 AAAs), under the second goes either the card reader or a RAM extension (like "Corvallis memory") and the third one is the optional HP-IL interface. BTW: It needs no time module, because it has an internal clock!

Greetings, Max

      
Re: 71B questions
Message #5 Posted by Egan Ford on 19 Aug 2007, 7:54 p.m.,
in response to message #1 by Vincze

The 71B has a 41CX looking zipper case, about as long but a bit wider. Here is a sold eBay listing with a picture of it:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=120146780352&ssPageName=STRK:MEWA:IT&ih=002

On the North side there are 2 ports, one is for a HP-IL only, the other is for the card reader or RAM module. IMHO, HP-IL is a must IF you have something to connect it to (PC, 9114 floppy drive, or HP-IL/RS232 bridge). I do all my development on EMU71 and then HP-IL it to my 71B via an HP-IL PC ISA card.

On the South size there are 4 general purpose RAM/ROM ports. I would recommend that you get a Math ROM.

I mentioned this before, but try the classifieds:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/adforum.cgi

Post a Want To Buy (WTB).

If you look now there is a FSBO HP 71B starting at $75.

Edited: 19 Aug 2007, 7:56 p.m.

            
Re: 71B questions
Message #6 Posted by Vincze on 19 Aug 2007, 8:23 p.m.,
in response to message #5 by Egan Ford

I email person selling, but I not know who he is. I am not sure I like buying from someone who I do not know. All other calculators I buy I actually got to see. Someone else email me that they have one too. I guess I need to put some trust in people.

                  
Re: 71B questions
Message #7 Posted by Egan Ford on 19 Aug 2007, 8:33 p.m.,
in response to message #6 by Vincze

Quote:
I guess I need to put some trust in people.
I trust the people here more than eBay.

Ask for pictures with the device powered up. Ask for a return policy. If you use Paypal you can leverage their dispute engine (never tried it).

IMHO, the rewards outweigh the risks.

      
Re: 71B questions
Message #8 Posted by Vincze on 19 Aug 2007, 8:09 p.m.,
in response to message #1 by Vincze

Thank you all. I wonder why does it need math module if it has BASIC and calculator built in. Also, I not sure I understand IL module. Is that like a IO port? What type of connector does it accept?

Lastly, they not all come with card reader? On card reader, is it one use only, or can one overwrite it with new program like disc?

            
Re: 71B questions
Message #9 Posted by Maximilian Hohmann on 19 Aug 2007, 8:17 p.m.,
in response to message #8 by Vincze

Hello!

Quote:
I wonder why does it need math module if it has BASIC and calculator built in.

The MATH module adds some additional functions (like matrix calculations) that you would have to program yourself otherwise. But even without this, the calculator has all functions that one really needs.

Quote:
Also, I not sure I understand IL module. Is that like a IO port? What type of connector does it accept?

Yes, it is a closed-loop serial connection. It has two special kinds of HP-IL connectors (in and out - like MIDI, only that MIDI uses the same connector for everything) that you will find nowhere else.

Quote:
Lastly, they not all come with card reader? On card reader, is it one use only, or can one overwrite it with new program like disc?

The card reader was an option. It is not really practical, because in the early 80ies, RAM sizes were growing fast and you needed heaps of cards to store the contents of the calculator memory (I think they hold 512 k each). I don't know for sure, because I don't have a card reader in my 71, only one in the '75, but that may be slightly different. The cards can be overwritten just like floppies. They are very hard to find and are differnt from the '65, '67, '97 and '41 cards, that are all the same and therefore in plenty supply.

Greetings, Max

Edited: 19 Aug 2007, 8:18 p.m.

                  
Re: 71B questions
Message #10 Posted by Raymond Del Tondo on 20 Aug 2007, 12:30 a.m.,
in response to message #9 by Maximilian Hohmann

Hi,

> [..Mag cards for HP-71..]
> (I think they hold 512 k each)
>
You certainly mean 512 bytes ;-)

Apart from that, according to the hpmuseum,
it was about 650 bytes per track,
or about 1300 bytes per card.

HTH

Raymond

            
Re: 71B questions
Message #11 Posted by Egan Ford on 19 Aug 2007, 8:19 p.m.,
in response to message #8 by Vincze

Quote:
I wonder why does it need math module if it has BASIC and calculator built in.
You do not need it, but you may want it. E.g. complex numbers, matrix operations. In 41CX terms think of it as an Advantage ROM, sans TVM.

Quote:
Also, I not sure I understand IL module. Is that like a IO port? What type of connector does it accept?
Yes. Read http://en.wikipedia.org/wiki/HP-IL. Bottom line it is proprietary and expensive, but fun.

Quote:
Lastly, they not all come with card reader? On card reader, is it one use only, or can one overwrite it with new program like disc?
Less than 1/2 (eBay) of them come with card readers. Yes you can reuse the cards. AFAIK, you cannot use the cards with a 41 or a PC, so its only useful to backup programs and share with others that have a 71B+card reader.
            
Re: 71B questions
Message #12 Posted by Howard Owen on 20 Aug 2007, 3:32 a.m.,
in response to message #8 by Vincze

Quote:
Lastly, they not all come with card reader?

No, not by a wide margin. The card readers are fairly rare, and pretty expensive when you do find one.

I think there are three reasons for this. First, as Raymond and Egan have said, the card reader was a pain to use because of the small capacity relative to the calculator's memory size. (You can get the cards on eBay pretty easily, by the way.) Second, the "card reader" port was actually used by lots of companies to take RAM/EPROM expansion modules. My main 71B has 128K in that port. Finally, the availibility of HP-IL meant that you could use several faster and higher capacity devices for storage. In particular, the 9114(A/B) floppy drive is quite usable from the 71B. It beats the cards hands down for both speed and capacity.

Regards,
Howard

                  
Re: 71B questions
Message #13 Posted by Vincze on 20 Aug 2007, 10:03 a.m.,
in response to message #12 by Howard Owen

Ok, so IL device best bet it sound like. how hard it to find IL cables?

                        
Re: 71B questions
Message #14 Posted by Maximilian Hohmann on 20 Aug 2007, 5:39 p.m.,
in response to message #13 by Vincze

Hello!

Quote:
how hard it to find IL cables?

Very hard, I'm afraid. I have quite a few IL devices (printers, micro-cassette-tape-readers and a video interface), but only one set of cables, so I can only use one at a time. In all the years I am after these things, I have only once seen IL cables on eBay and they went for a price that would have earned me a divorce if I had spent so much on so little... Maybe in the States the situation is different? (Same as with the "long" magnetic cards for the 71 and 75 that are almost impossible to find here.)

Greetings, Max

                              
Re: 71B questions
Message #15 Posted by Egan Ford on 20 Aug 2007, 5:53 p.m.,
in response to message #14 by Maximilian Hohmann

1m cables average $10-$20 each on eBay. You will need at least two unless you are talking to an 41C only, the HP-IL adapter for the 41 has cables hardwired.

                                    
Re: 71B questions
Message #16 Posted by Vincze on 20 Aug 2007, 9:04 p.m.,
in response to message #15 by Egan Ford

Why need two? I just wish to talk to my laptop which have rs232 port. Do I still need two?

                                          
Re: 71B questions
Message #17 Posted by Egan Ford on 20 Aug 2007, 9:53 p.m.,
in response to message #16 by Vincze

Please read:

http://en.wikipedia.org/wiki/HP-IL

http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1983-01.pdf

IANS, HP-IL is not RS232. You need a gateway/bridge to get from HP-IL to your laptop. Your options are:

  1. HP-IL PC ISA card in a old PC with network support (this is what I do and it works great and is very easy to do with Linux+EMU71 and/or EMU41)
  2. HP-IL to RS-232 (cumbersome, one program at a time)
  3. 9114 HP-IL floppy drive (floppies can be read/written from Linux).

All three options require at least two HP-IL cables--its a loop.

#1 is clearly the best way to go. Take an old PC (with ISA slots), install an HP-IL adapter, install Linux+DOSEMU, install EMU71 (registered version), and install a network adapter. Now you have an HP-IL appliance. It emulates 2 virtual floppies (9114), can emulate a HP-IL to RS-232 device, a printer, and an 80 column display. Do all your development on your laptop with EMU71, then copy the virtual floppy image to your HP-IL appliance (no need to restart EMU71), then from your 71B you can directly access the virtual floppy drive using easy 71B commands. Get fancy and export the DOSEMU directory, mount on your laptop and share the virtual floppy drive.

#2 is a more work, not as flexible or simple.

#3 is easy. But the diskettes can only be formatted in the 9114 (not Linux, DOS OK) and the diskettes can only be read/write from DOS or Linux (no Windows).

                                                
Re: 71B questions
Message #18 Posted by Vincze on 21 Aug 2007, 9:33 a.m.,
in response to message #17 by Egan Ford

My friend Egan, how hard it to find the IL ISA card? One other issue. My laptop not have floppy drive. Just CD and flash drive, so I would have to have PC that can read flash drive. Hmmm... This getting more complicated. :(

                                                      
Re: 71B questions
Message #19 Posted by Egan Ford on 21 Aug 2007, 10:53 a.m.,
in response to message #18 by Vincze

Quote:
My friend Egan, how hard it to find the IL ISA card?
Very hard. I have never seen one on eBay. However, there is one for sale now (check the Classifieds).

Quote:
One other issue. My laptop not have floppy drive. Just CD and flash drive, so I would have to have PC that can read flash drive. Hmmm... This getting more complicated. :(
The 71B is 22 years old. You are going to need an old PC if you want to use HP-IL/ISA. Perhaps HP-IL -> RS/232 is the answer for you.
                                                            
Re: 71B questions
Message #20 Posted by Vincze on 21 Aug 2007, 10:57 a.m.,
in response to message #19 by Egan Ford

How does HP-IL - RS232 work? Connect one to IL, and other end to serial port on PC? How is loop made though?

Edited: 21 Aug 2007, 10:57 a.m.

                                                                  
Re: 71B questions
Message #21 Posted by Egan Ford on 21 Aug 2007, 11:59 a.m.,
in response to message #20 by Vincze

Please, please read:

http://en.wikipedia.org/wiki/HP-IL

http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1983-01.pdf

IANS:

 .------------------.
 |                  |
 |       71B        |
 '__________________'
    IN |     | OUT
       |     |
       |     |        <- 2 HP-IL cables (this is your loop)
       |     |
   OUT |     | IN
     .---------.
     |  HP-IL  |
     | RS-232C |
     '---------'
        \DB25/
          ||
          ||
          ||
        /DB9 \
 .------------------.
 |                  |
 |      Laptop      |
 '__________________'

Edited: 21 Aug 2007, 12:02 p.m.

                                                                        
Re: 71B questions
Message #22 Posted by Dave Colver on 21 Aug 2007, 12:18 p.m.,
in response to message #21 by Egan Ford

(anticipates Vincze's next question - yes there are USB to serial port converters made :))

                                                                              
Re: 71B questions
Message #23 Posted by Vincze on 21 Aug 2007, 12:54 p.m.,
in response to message #22 by Dave Colver

Thank you my friend, yes I know there are USB/Serial converter, but good you thought of it regardless. ;)

                                                                        
Re: 71B questions
Message #24 Posted by Vincze on 21 Aug 2007, 12:44 p.m.,
in response to message #21 by Egan Ford

Okay, that explain. I did not aware that there was box between PC and 71B. I thought cable went direct between 71B and computer. Now I understand.

So with ISA card, there no box between PC and 71B. You have two wires from 71B and PC that connect, yes? Wow... this seem like a lot just to transfer program, but I see value of backing up 71B.

Well, now I wait for my 71B to arrive. I just happy that I able to find one.

How hard Math module to find, and how much they normally go for?

                                                                              
Re: 71B questions
Message #25 Posted by Egan Ford on 21 Aug 2007, 1:38 p.m.,
in response to message #24 by Vincze

Quote:
So with ISA card, there no box between PC and 71B. You have two wires from 71B and PC that connect, yes?
Yes.

.------------------. | | | 71B | '__________________' IN | | OUT | | | | <- 2 HP-IL cables (this is your loop) | | OUT | | IN .-----------. | OLD PC | | HP-IL ISA | '-----------' | | <- Ethernet/WiFi/IP | .------------------. | | | Laptop | '__________________'

Quote:
How hard Math module to find, and how much they normally go for?
No very. ~$100. Optionally you can post a WTB for a burned ROM with Math+JPC. Or you can install a 32K RAM module put it there (but you will need HP-IL to do that).
                                                                                    
Re: 71B questions
Message #26 Posted by Vincze on 21 Aug 2007, 3:14 p.m.,
in response to message #25 by Egan Ford

How much is burned Rom with math and JPC?

                                                                                          
Re: 71B questions
Message #27 Posted by Egan Ford on 21 Aug 2007, 3:27 p.m.,
in response to message #26 by Vincze

See Howard's reply below.

                                                                                                
Re: 71B questions
Message #28 Posted by Vincze on 21 Aug 2007, 3:44 p.m.,
in response to message #27 by Egan Ford

$300!!?? Szent juh szar! Are you kidding me? That crazy for old computer part.

                                                                                                      
Re: 71B questions
Message #29 Posted by Maximilian Hohmann on 21 Aug 2007, 4:01 p.m.,
in response to message #28 by Vincze

Hello!

Quote:
$300!!?? Szent juh szar! Are you kidding me? That crazy for old computer part.

You are perfectly right. Especially, since this is not really an old computer part, but fairly recent. For this amount of money, you could get yourself a Curta (almost) and believe me, apart from being more than twice as old, it will give you infinitely more pleasure and satisfaction! And it cannot be run on an emulator :-)

Greetings, Max

                                                                                                            
Re: 71B questions
Message #30 Posted by Raymond Del Tondo on 21 Aug 2007, 6:39 p.m.,
in response to message #29 by Maximilian Hohmann

Hi,

IIRC there exists at least one Curta simulator...

Raymond

                                                                                                                  
Re: 71B questions
Message #31 Posted by Vincze on 21 Aug 2007, 9:06 p.m.,
in response to message #30 by Raymond Del Tondo

Quote:

IIRC


?????
                                                                                                                        
Re: 71B questions
Message #32 Posted by Garth Wilson on 22 Aug 2007, 2:32 a.m.,
in response to message #31 by Vincze

IIRC = if I remember correctly
IOW = in other words
IMO = in my opinion
IMHO = in my humble opinion
FWIW = for whatever it's worth
LOL = laugh out loud
There are many more. It's convenient for writing, but hard on newcomers and foreigners.

Edited: 22 Aug 2007, 2:33 a.m.

                                                                                                                        
Re: 71B questions
Message #33 Posted by Vincze on 22 Aug 2007, 9:44 a.m.,
in response to message #32 by Garth Wilson

Who you calling a foreigner? ;)

                                                                                                                  
Re: 71B questions
Message #34 Posted by Thomas Klemm on 22 Aug 2007, 3:55 a.m.,
in response to message #30 by Raymond Del Tondo

Curta Simulation

                                                                                                                        
Re: 71B questions
Message #35 Posted by Dave Shaffer (Arizona) on 22 Aug 2007, 11:24 a.m.,
in response to message #34 by Thomas Klemm

Is there an instruction manual for those of us not familiar with how this gizmo and its simulator works!?

I kept trying to grab the arrows until I realized all I need to do was click them, but I still don't know how to multiply, divide, etc., although I have an inkling after a bit of playing.

                                                                                                                        
Re: 71B questions
Message #36 Posted by Thomas Klemm on 22 Aug 2007, 1:22 p.m.,
in response to message #35 by Dave Shaffer (Arizona)

Simulator & Bedienung or Simulator & operation or here
The guidances are all in German but you may use Google to translate them.

Hope this helps

Edited: 22 Aug 2007, 1:55 p.m.

                                                                                                                        
Babbage Emulator??
Message #37 Posted by Vincze on 22 Aug 2007, 2:51 p.m.,
in response to message #36 by Thomas Klemm

Anyone have a Babbage emulator? Just curious... I would like to see it spew steam and all.

Edited: 23 Aug 2007, 8:43 a.m. after one or more responses were posted

                                                                                                                        
Re: Babbage Emulator??
Message #38 Posted by Paul Dale on 22 Aug 2007, 4:56 p.m.,
in response to message #37 by Vincze

Forget an emulator, try the real thing: Difference Engine, Larger Difference Engine and partially complete Analytical Engine. Also of interest is the Differential Analyzer. All the videos are worthwhile.

Even though these aren't my constructions, Meccano is one of my other hobbies :-)

- Pauli

                                                                                                                        
Re: Babbage Emulator??
Message #39 Posted by Thomas Klemm on 23 Aug 2007, 8:14 a.m.,
in response to message #38 by Paul Dale

Quote:
Meccano is one of my other hobbies

Then you might like Meccano Math by Gerard ít Hooft.

                                                                                                                        
unacceptable language on the forum
Message #40 Posted by Don Shepherd on 22 Aug 2007, 7:26 p.m.,
in response to message #37 by Vincze

Vincze, you have begun to use language on this forum that I and, I am sure, others find offensive. This is a civilized community, and your choice of language is inappropriate.

                                                                                                                        
Re: Babbage Emulator??
Message #41 Posted by Howard Owen on 22 Aug 2007, 8:50 p.m.,
in response to message #37 by Vincze

That language won't fly here, Vincze.

This forum has participants from a wide variety of backgrounds, Vincze. It's best to assume that anything even slightly off-color might offend someone. The museum terms of use say that you shouldn't post material that is ".. vulgar, hateful, harassing, obscene, profane, .." among many other categories. And it's the curator's interpretation of those categories that matters, not yours or mine.

Please take this as friendly advice and nothing else.

Regards,
Howard

                                                                                                                        
Re: Babbage Emulator??
Message #42 Posted by Vincze on 23 Aug 2007, 8:43 a.m.,
in response to message #41 by Howard Owen

I very sorry.

                                                                                                                        
Re: Babbage Emulator??
Message #43 Posted by Howard Owen on 22 Aug 2007, 8:54 p.m.,
in response to message #37 by Vincze

There's no working hardware model of the Analytical Engine, as far as I know. I have seen several scale models of the Difference Engine, however. (And there's a full scale model in Britain, I believe.) None of those run on steam, unlike the imagined mechanical computers of "The Difference Engine" novel.

Regards,
Howard

                                                                                                                        
Re: Babbage Emulator??
Message #44 Posted by Howard Owen on 22 Aug 2007, 9:07 p.m.,
in response to message #37 by Vincze

I should have read Paul's post before my last. The Meccano site contains a link to a 40MB Quicktime video of a working model of one of the Analytical Engine's components. This is not a direct implementation from the plans, but an embodiment of the ideas contained in the plans. For example, it is made from a Meccano building kit with modern materials, and appears to be powered with an electric motor.

Regards,
Howard

                                                                                                      
Re: 71B questions
Message #45 Posted by Howard Owen on 21 Aug 2007, 5:23 p.m.,
in response to message #28 by Vincze

The burned ROM is around $100.00.

                                                                              
Re: 71B questions
Message #46 Posted by Howard Owen on 21 Aug 2007, 1:50 p.m.,
in response to message #24 by Vincze

The math module is pretty hard to find, and expensive when you do find one.

The alternative I took was to send a CMT 64K front port EEPROM module I had acquired on eBay to Mike Davis. He has a programmer for those devices. I asked him to put the math module and the JPC ROM images on mine. I now have the functional equivalent of both those very rare modules in a single front port module. Mike occasionally sells similar EEPROMs on eBay, along with the burning service. The 64K version goes for $100.00 or so.

Another possibility is to acquire a large RAM expansion module. You can then configure it as a detached memory, and fill it with the math module image and whatever else will fit. The images for most of the historical modules for the 71B are all on the swap disks. This won't work for the FORTH/Assembler or HP41 Translator modules. These modules take over the OS of the 71B at a lower level, and can't be configured to run out of a detached RAM or EEPROM. Those modules are therefore expensive when they come up on eBay. $300.00 or so is typical.

Also, with respect to the HP-IL cables, I got most of mine by acquiring 71B and 41C bundles from eBay. Generally speaking, a large lot of equipment is a far better deal on eBay than single item auctions. I'm not sure why, but people seem not to bid as high for lots as they do for the single items. That's how I got my CMT EEPROM and other goodies as well.

Regards,
Howard

Edited: 21 Aug 2007, 1:54 p.m.


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