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71B Math ROM, is there an alternative?
Message #1 Posted by Egan Ford on 17 Mar 2007, 1:54 p.m.

Math ROMs are scarce, is there an alternative?

Thanks.

      
Re: 71B Math ROM, is there an alternative?
Message #2 Posted by Eric Smith on 17 Mar 2007, 2:19 p.m.,
in response to message #1 by Egan Ford

An HP 50G? :-)

      
Re: 71B Math ROM, is there an alternative?
Message #3 Posted by JeffD on 17 Mar 2007, 2:30 p.m.,
in response to message #1 by Egan Ford

If you can find a 32K Ram Module then you could find the Math Rom on the internet and load this onto your HP-71B using the 9114 disc drive. The Ram modules might be easier to find???

      
Re: 71B Math ROM, is there an alternative?
Message #4 Posted by Namir on 17 Mar 2007, 3:37 p.m.,
in response to message #1 by Egan Ford

The HP-71B emulator by J-F Garnier has the MATH ROM included in the software.

Namir

      
Re: 71B Math ROM, is there an alternative?
Message #5 Posted by Howard Owen on 18 Mar 2007, 3:20 a.m.,
in response to message #1 by Egan Ford

I obtained a 64K CMT EEPROM with a 71 I bought off eBay. I also had a 32K EEPROM I had acquired earlier. I cut a deal with Mike (his username on this board is "Mike") to program the 64K chip in exchange for the 32K chip. I chose the math ROM and the JPCROM, plus a few other miscellaneous LEX files. Mike sells 64K and 32K EEPROMs on eBay along with the service of burning whatever software you supply him with onto the parts before he ships them to you. It's generally a lot cheaper than trying to outbid other collectors for the rare add-ons like the math ROM.

You can also just copy MATHROM.LEX (available on the swap disks) into RAM if you have enough. It works fine that way.

Regards,
Howard

      
Re: 71B Math ROM, is there an alternative?
Message #6 Posted by Valentin Albillo on 19 Mar 2007, 8:17 a.m.,
in response to message #1 by Egan Ford

Hi, Egan:

Egan posted:

    "Math ROMs are scarce, is there an alternative?"

      They're scarce indeed if offered individually, but much less when bundled with the HP-71B itself.

      A couple of years ago I found someone offering several HP-71B for auction. The add only mentioned that they were clean, working, and included an HP-IL module and a 4 Kb RAM module, all ports, etc. I got three of them for just $150 in all.

      Once they arrived, I was astonished when I saw that not only were the machines virtually mint (with just a small case of battery corrosion which simply required a minor clean job of the battery contacts with a cloth) and working perfectly, but each and everyone of them did also include a mint, working Math ROM plugged in, which wasn't even mentioned in the add.

      I guess these machines were part of a larger lot belonging to some company which decided to get rid of them all, including backup, never used models which had been in store for a long time (thus the minor corrosion in one of them and their pristine status). Their business obviously did require HP-IL and Math ROM functionality (matrices or complex arithmetic, most likely), plus 4 Kb extra RAM, so all their calcs did include all three modules. The seller was obviously unaware of such finesses and was merely getting rid of the lot for what he/she considered a fair amount for such obsolete, weird handhelds ($50-$70).

      Perhaps you could also have a look at HP-71Bs offered to see if they might perchance include a Math ROM, which seems much more likely than finding the individual ROM, most specially if the seller isn't very knowledgeable about what he/she's selling.

Best regards from V.

      
Re: 71B Math ROM, is there an alternative?
Message #7 Posted by Egan Ford on 19 Mar 2007, 7:55 p.m.,
in response to message #1 by Egan Ford

Thanks for all the responses.

Eric, I have a 50G, but desire a more complete 71B. I am a fan of the Voyagers (best calculators--ever), the 71B is like an expandable 11C, but I need the ROM to make it more 15C-like (best Voyager--ever).

JeffD, I think getting the 9114 may be harder and I do not have the RAM (yet). If a fellow 71Ber and I both had HP-IL could it be transferred that way? I hope my batteries never die.

Namir, got it and use it. Very nice. The simulated 80 column display is also nice. [rumor]I look forward to the upcoming GUI based on emu48[/rumor].

Howard, great idea. "Mike", if you are listening, message me when you have EEPROMs in stock.

Valentin, with buyers asking more questions and sellers posting the answers the odds are low for such a pleasant surprise. But I will try.

Thanks.

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