conte@uicsrd.CSRD.UIUC.EDU (03/06/87)
Well, I bought the printer for the HP-28C, the HP82240A. It is compact,
lightweight, but has some drawbacks. One is it produces a lot of noise,
sort of a mini-dinosaur-- not the type of thing one wants to use in the
library. Also, it has strange battery requirements: as the battery
wears down, it will print slower. With an AC adapter, you can set a
flag in the `28C, and the thing cranks, but draws power from the batteries
to do so. All in all, though, it is a nice little printer. I hope
someone in Corvallis gets the idea to make a module for the `41 to
run the thing. That would be great.
Tom Conte Center for Supercomputing Research & Development
University of Illinois
uucp: ...!uiucdcs!uicsrd!conte bitnet: conte@uicsrd.csrd.uiuc.edu
arpanet: conte%uicsrd@a.cs.uiuc.edu (or conte@huey.udel.edu)graeme@zen.UUCP (03/21/87)
In article <44700002@uicsrd> conte@uicsrd.CSRD.UIUC.EDU writes: > >Well, I bought the printer for the HP-28C, the HP82240A. It is compact, >lightweight, but has some drawbacks. One is it produces a lot of noise, >sort of a mini-dinosaur-- not the type of thing one wants to use in the >library. Also, it has strange battery requirements: as the battery >wears down, it will print slower. With an AC adapter, you can set a >flag in the `28C, and the thing cranks, but draws power from the batteries >to do so. All in all, though, it is a nice little printer. I hope >someone in Corvallis gets the idea to make a module for the `41 to >run the thing. That would be great. > > >Tom Conte Center for Supercomputing Research & Development > University of Illinois > The main problem, as I see it, with the 28C I/O is the fundamental lack of "I". Corvallis products have, in the past, been noted for their high reliability of both software and hardware. One could always rely on the calculator's operating system to protect the user from entering invalid operations and reporting errors with reasonably meaningful messages. This security has all but been discarded with the 28C and its printer. The 28 happily blasts (or more accurately oozes) out data into thin air hoping there is something out there ready to receive it. It has no way of knowing if the data has been received correctly, or indeed at all. This might be slightly more acceptable if there was some physical connection between the calculator and its printer as this would eradicate the possibility of two calcs trying to talk to the same printer; it would also eliminate the problem of paper and the like blocking the dataflow - a common problem on my desk. At least they should have added a checksum at the end of each line of output so the printer could verify what it had received. As for the quality of the printer itself: its slow, noisy and generally tacky - I wouldn't let it near my 41. And the 28C? The power of this calculator is absolutely phenomenal. I am constantly amazed at the things it can do. It can solve complex problems in a matter of seconds; its just such a shame it takes a matter of hours to work out how. This is thanks mainly to the 28C manuals which rival the 82240 printer in the (lack of) quality stakes. As for the programming language - this defies comprehension. Never before have I come across a language that uses prefix, infix AND postfix notation in one statement. ...nuff said? Graeme Cawsey [graeme@zen.uucp<->..!mcvax!ukc!zen.co.uk!graeme] Senior Programmer Zengrange Ltd. Disclaimer: The above expressed opinions are mine and belong to me. I tried to sell them to my employer but he wasn't interested. My employer believes that all CVD products are wonderful. :-)
roy@phri.UUCP (03/24/87)
In article <590@zen.UUCP> graeme@zen.UUCP (Graeme Cawsey) writes: > Never before have I come across a language that uses prefix, infix AND > postfix notation in one statement. What about C? You can do "x = ++i + j++;", can't you? -- Roy Smith, {allegra,cmcl2,philabs}!phri!roy System Administrator, Public Health Research Institute 455 First Avenue, New York, NY 10016 "you can't spell deoxyribonucleic without unix!"
daver@hpsgpa.UUCP (03/25/87)
>..................................................... One could >always rely on the calculator's operating system to protect the user >from entering invalid operations and reporting errors with reasonably >meaningful messages. This security has all but been discarded with >the 28C and its printer. The 28 happily blasts (or more accurately >oozes) out data into thin air hoping there is something out there >ready to receive it. It has no way of knowing if the data has been >received correctly, or indeed at all. > >This might be slightly more acceptable if there was some physical >connection between the calculator and its printer as this would >eradicate the possibility of two calcs trying to talk to the same >printer; it would also eliminate the problem of paper and the like >blocking the dataflow - a common problem on my desk. At least they >should have added a checksum at the end of each line of output so the >printer could verify what it had received. A printer is an interesting device from this point of view, since it provides instant feedback via the user. The printer was designed to be reliable and inexpensive. The IR range was deliberately limited to avoid the problem of interference between two calculators being used on adjacent desks. Each byte of data has an additional 4 bits of error-correction code which will correct single-bit and many double-bit errors and detect most other errors. In addition, there are several levels of redundancy in the encoding of individual bits to make the printer as immune as possible to outside interference. Accidentally placing paper between the calculator and printer is equivalent to accidentally pulling out the cable between a wired calculator and printer. The printer was designed to be easy to use and inexpensive (compare the price to the older HP printers), and it is. It is also capable and reliable, in the HP tradition. Dave Rabinowitz hplabs!hp-pcd!daver
frank@zen.UUCP (03/27/87)
In article <2613@phri.UUCP> roy@phri.UUCP (Roy Smith) writes: >In article <590@zen.UUCP> graeme@zen.UUCP (Graeme Cawsey) writes: >> Never before have I come across a language that uses prefix, infix AND >> postfix notation in one statement. > > What about C? You can do "x = ++i + j++;", can't you? But please remember the context of the language -- this is a *calculator*, intended for use as a problem-solving tool; for many of its Users, it will be their first exposure to computer programming. Anybody who tries to learn programming as a skill by learning C would be asking for trouble -- its inconsistencies would obscure its benefits for computer neophytes -- and anybody who believes otherwise has no business designing systems for non-computerate end-Users (I don't think Roy is in this category). So it is vital that the language on such a machine have as unhirsute a syntax as possible, and I don't believe enough thought has gone into the programming language [or, for that matter, the general User-interface] on the 28C for this to be true. >Roy Smith, {allegra,cmcl2,philabs}!phri!roy Frank Wales [frank@zen.uucp<->..!mcvax!ukc!zen.co.uk!frank] hand-held systems Development Engineer (and long-time calculator User) [^^^^ ^^^^ ...this doesn't mean I'm a pixie, by the way...] Zengrange Limited, Greenfield Rd., Leeds, England +44 532 489048 x220
jules@zen.UUCP (03/29/87)
In article <2790003@hpsgpa.HP.COM> daver@hpsgpa.HP.COM (Dave Rabinowitz) writes: >A printer is an interesting device from this point of view, since it provides >instant feedback via the user. The printer was designed to be reliable and >inexpensive. The IR range was deliberately limited to avoid the problem of >interference between two calculators being used on adjacent desks. Each byte >of data has an additional 4 bits of error-correction code which will correct >single-bit and many double-bit errors and detect most other errors. In >addition, there are several levels of redundancy in the encoding of individual >bits to make the printer as immune as possible to outside interference. Why aren't there check codes for complete lines, or even better, large blocks of data, so that when the printer notices something wrong it could flash one of its LED's to say that an error has occurred ? Another idea might be to have sequence codes in with each block of data so that the printer can spot a missing block. >Accidentally placing paper between the calculator and printer is equivalent to >accidentally pulling out the cable between a wired calculator and printer. .. WHAT? They might be equivalent in terms of data loss, but not in terms likelihood of happening. >.......................................................................... The >printer was designed to be easy to use and inexpensive (compare the price to >the older HP printers), and it is. It is also capable and reliable, in the HP >tradition. Admittedly the printer is (by HP standards) reasonably inexpensive, but that is no excuse for it being (like the 18C and 28C) not up to HP's normally very high standards. I, and most other people who buy HP calculators and hand-held computers, expect to pay more for them because they are better made, more reliable, well designed and tend to do just about anything you want them to. The HP-41 has all of the above features (including a high price tag) and it has sold over a million. Is that such a bad formula to try and stick to. If HP are not careful then they will end up producing the same old boring cheap and nasty calculators that everybody else does. By the way, PLEASE DON'T DITCH RPN, anyone who has used it wouldn't buy anything else and it is sickening to see a trend in HP towards the AOS system. Owners of HP calculators must be the most loyal of users, but they won't be if HP's commitment to RPN doesn't continue. Jules -- IN-REAL-LIFE: Julian Perry E-MAIL: jules@zen.co.uk || ...!mcvax!ukc!zen.co.uk!jules PHONE: +44 532 489048 ext 217 ADDRESS: Zengrange Limited, Greenfield Road, Leeds, England, LS9 8DB
JWHOLT01@ULKYVX.BITNET (05/23/88)
I am interested in getting some more information on the HP-28C I want to know more about the SYSEVAL stuff. I have the clock programs and that is about all. Our site seems to miss a lot of information or something, so if someone could email me what they have on the 28c I would appreciate it. This is my first posting so if you don't like this let me know so I can improve next time. thanks again. ------------------------------------------------------------------------- John W Holthaus 2000 Confederate Place Apt 503 Louisville, KY 40208 UUCP: ...!psuvax1!ulkyvx.bitnet!jwholt01 BITNET: jwholt01@ulkyvx INTERNET: jwholt01%ulkyvx.bitnet@cunyvm.cuny.edu
cloos@batcomputer.tn.cornell.edu (James H. Cloos Jr.) (05/31/88)
I'm also interested in SYSEVAL stuff. The previous poster mentioned clock programs et. al., though I don't recognise the references. Any interesting programs anyone can send would be greatly appreciated, & I'll post a note about my current program if I ever finish the thing... :-) -JimC -- batcomputer!cloos@cornell.UUCP |James H. Cloos, Jr.|#include <disclaimer.h> cloos@batcomputer.tn.cornell.EDU|B7 Upson, Cornell U|#include <cute_stuff.h> cloos@tcgould.tn.cornell.EDU |Ithaca, NY 14853 |"Entropy isn't what cloos@crnlthry.BITNET | +1 607 272 4519 | it used to be."