Connection limitations on the 50g - Hewlett Packard

This is a discussion on Connection limitations on the 50g - Hewlett Packard ; I'm kind of newbie to the 50g (and hp calculators in general, for that matter), but am kind of psyched about messing around with HPGCC as I already know C/C++ fairly well. Anyway, my question, which may have already been ...

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  1. Connection limitations on the 50g

    I'm kind of newbie to the 50g (and hp calculators in general, for that
    matter), but am kind of psyched about messing around with HPGCC as I
    already know C/C++ fairly well.

    Anyway, my question, which may have already been answered some time
    ago (can't find any straight answers though, so) is what are the
    limitations of the onboard communications on the 50g? I know the
    calculator can use Kermit and XMODEM, and that pretty spectacular
    things have been done so far (Usinagaz). I'm interested in using
    either the RS232 serial port or the USB port to connect to other
    devices and ultimately collect data from them or control them, i.e. a
    PLC, a USB ethernet adapter, surveying equipment, etc. I'm not at all
    interested in using IrDA.

    I read another thread saying something about the calculator being a
    USB peripheral which apparently poses some limitations that I'm not
    seeing, as I thought the 50g can both send and receive (through all
    three IrDA, USB and RS232). Anyway, thanks in advance for any
    pertinent information on this subject.

    Cheers, Jake

  2. Re: Connection limitations on the 50g

    On Jul 18, 12:32*pm, thatcad...@gmail.com wrote:
    > I'm kind of newbie to the 50g (and hp calculators in general, for that
    > matter), but am kind of psyched about messing around with HPGCC as I
    > already know C/C++ fairly well.
    >
    > Anyway, my question, which may have already been answered some time
    > ago (can't find any straight answers though, so) is what are the
    > limitations of the onboard communications on the 50g? I know the
    > calculator can use Kermit and XMODEM, and that pretty spectacular
    > things have been done so far (Usinagaz). I'm interested in using
    > either the RS232 serial port or the USB port to connect to other
    > devices and ultimately collect data from them or control them, i.e. a
    > PLC, a USB ethernet adapter, surveying equipment, etc. I'm not at all
    > interested in using IrDA.
    >
    > I read another thread saying something about the calculator being a
    > USB peripheral which apparently poses some limitations that I'm not
    > seeing, as I thought the 50g can both send and receive (through all
    > three IrDA, USB and RS232). Anyway, thanks in advance for any
    > pertinent information on this subject.
    >
    > Cheers, Jake


    P.S. If I've been too vague about the kind of things I'm wanting to do
    here, the article Egan posted a few days back about controlling an XP
    computer using the serial port through SerialKeys (http://
    www.sense.net/~egan/skb/) is right up my alley.

  3. Re: Connection limitations on the 50g

    On Jul 18, 12:32*pm, thatcad...@gmail.com wrote:
    > I'm kind of newbie to the 50g (and hp calculators in general, for that
    > matter), but am kind of psyched about messing around with HPGCC as I
    > already know C/C++ fairly well.
    >
    > Anyway, my question, which may have already been answered some time
    > ago (can't find any straight answers though, so) is what are the
    > limitations of the onboard communications on the 50g? I know the
    > calculator can use Kermit and XMODEM, and that pretty spectacular
    > things have been done so far (Usinagaz). I'm interested in using
    > either the RS232 serial port or the USB port to connect to other
    > devices and ultimately collect data from them or control them, i.e. a
    > PLC, a USB ethernet adapter, surveying equipment, etc. I'm not at all
    > interested in using IrDA.
    >
    > I read another thread saying something about the calculator being a
    > USB peripheral which apparently poses some limitations that I'm not
    > seeing, as I thought the 50g can both send and receive (through all
    > three IrDA, USB and RS232). Anyway, thanks in advance for any
    > pertinent information on this subject.
    >
    > Cheers, Jake


    IIRC the IR is highly distance limited, although I forget which
    direction is the limiting one, or if both are roughly equal.

    USB is a very complicated protocol, and the calculator is designed
    only to use a special protocol over usb intended for connecting to a
    computer. I'd be very surprised if anybody could do anything
    interesting with the Hp50g's USB port besides connect to a commputer,
    or specially designed hardware specifically for the purpose.

    The serial port has some limitations, but I really don't remember the
    details. I'll let somebody else more experienced with this give the
    details.

    However for what it is worth, all of the limitations can be worked
    around with external hardware. For example, when designing their HP50g-
    based surveying data-collector, Precision Surveying Solutions, LLC.
    used an external serial communications board to overcome the
    limitations of the built-in serial port. They are friendly enough
    people that I'm sure they would be willing to tell you anything
    special about interfacing the hp50g to other equipment that they
    happen to know. They also probably have the most experience with
    interfacing the HP50g with external equipment. They do read this
    newsgroup, or you can contact them by visiting their web site pssllc.com>.

  4. Re: Connection limitations on the 50g

    The serial port isn't really limited at all once you get a good cable,
    like from Eric at HPCALC.org

    There is a workaround for getting 1200 BAUD using a simple little
    software trick developed by Claudio Lapilli. The info is on Eric's
    page that has the cable.

    > However for what it is worth, all of the limitations can be worked
    > around with external hardware. For example, when designing their HP50g-
    > based surveying data-collector, Precision Surveying Solutions, LLC.
    > used an external serial communications board to overcome the
    > limitations of the built-in serial port.


    Well, the actual thing was the desire to have bluetooth on there that
    drove us. Having a fully programmable controller to handle the
    communications allows lots of great stuff though.

    > They are friendly enough
    > people that I'm sure they would be willing to tell you anything
    > special about interfacing the hp50g to other equipment that they
    > happen to know.


    Hmm. . . "friendly enough". Enough as is acceptable? Maybe I look
    grumpy. . . ;-)

    > They also probably have the most experience with
    > interfacing the HP50g with external equipment.


    Maybe for surveying stuff, but nothing else.

    TW

  5. Re: Connection limitations on the 50g

    wrote:
    > I read another thread saying something about the calculator being a
    > USB peripheral which apparently poses some limitations that I'm not
    > seeing, as I thought the 50g can both send and receive (through all
    > three IrDA, USB and RS232). Anyway, thanks in advance for any
    > pertinent information on this subject.


    USB generally acts in two different modes: as a host or as a peripheral (I'm
    excluding USB On-The-Go here, because no HP calculators use that). USB
    peripherals are the simplest, because all they have to do is operate with
    the USB port in a single, predetermined manner. USB hosts, on the other
    hand, need to know that "single, predetermined manner" for each and every
    USB peripheral they want to communicate with. For this reason, USB hosts
    use drivers that allow the host to speak the right language with the
    peripheral.

    The 50g was designed to act as a USB peripheral, and HP has provided a
    driver that runs on a Windows-based host to communicate with it.
    Third-party developers have written drivers for other platforms, such as
    Linux.

    The 50g was not designed to act as a USB host, and even if it could, you'd
    still have the problem of needing to obtain a driver for every USB
    peripheral you wanted to connect to it. It's hard enough to get device
    manufacturers to write drivers for even common platforms like Linux or
    MacOS -- it would be nearly impossible to convince anyone to write a driver
    for a platform as obscure as the 50g. Given enough time you could probably
    write one yourself, especially if an existing open-source driver exists for
    another platform, but that would take a lot of effort.

    If you want to connect to other devices, use the RS-232 serial port. Most
    serial devices that you would be likely to communicate with have their
    protocol documented, so it should be as simple as reading the documentation
    and using the XMIT and SRECV commands appropriately.

    Regards,

    Eric Rechlin



  6. Re: Connection limitations on the 50g

    On Fri, 18 Jul 2008 14:48:03 -0500, TW wrote:

    > The serial port isn't really limited at all once you get a good cable,
    > such as from [ http://commerce.hpcalc.org ]


    Was "transmit/receive pacing" a/k/a "flow control" (via "X-on/X-off")
    ever restored? (all original HP48S/G series had it, HP49G did not)

    This was an app-killer for larger data blocks, IIRC,
    mentioned in some posts by James M. Prange:
    http://groups.google.com/group/comp....c297c7370f2d47
    http://groups.google.com/group/comp....5959d29067bd3f

    English translation:

    While a stream of data is being transferred in either direction,
    the receiver can not tell the sender, via two special characters
    (X-on/X-off), when to pause and then resume, so that the receiver
    can catch up with processing its receive buffer,
    to avoid an "overrun" (end of buffer, no way to receive any more).

    References for Xon/Xoff:
    http://whatis.techtarget.com/definit...213406,00.html
    http://www.computerhope.com/jargon/x/xonxoff.htm
    http://docs.hp.com/en/32022-90051/ch09s08.html
    http://publib.boulder.ibm.com/infoce...ontrol_xon.htm

    -[ ]-

  7. Re: Connection limitations on the 50g

    Eric Rechlin kirjutas:
    > wrote:
    >> I read another thread saying something about the calculator being a
    >> USB peripheral which apparently poses some limitations that I'm not
    >> seeing, as I thought the 50g can both send and receive (through all
    >> three IrDA, USB and RS232). Anyway, thanks in advance for any
    >> pertinent information on this subject.

    >
    > If you want to connect to other devices, use the RS-232 serial port. Most
    > serial devices that you would be likely to communicate with have their
    > protocol documented, so it should be as simple as reading the documentation
    > and using the XMIT and SRECV commands appropriately.
    >

    For what it's worth: 50g has one more communication port! I read from
    somewhere, probably from comp.sys.hp48 discussion, that 50g has full
    blown SDIO hardware. The problem: no driver to use this functionality
    If the SDIO would work then one could use SDIO bluetooth, SDIO WiFi,
    SDIO whatever. And of course, this is unconfirmed...

    Best wishes,

    Robert Tiismus

  8. Re: Connection limitations on the 50g

    On Fri, 18 Jul 2008 15:38:32 -0500, Robert Tiismus wrote:

    > For what it's worth: 50g has one more communication port!
    > I read from somewhere, probably from comp.sys.hp48 discussion,
    > that 50g has full blown SDIO hardware.
    > The problem: no driver to use this functionality


    > If the SDIO would work then one could use SDIO bluetooth, SDIO WiFi,
    > SDIO whatever. And of course, this is unconfirmed...


    Cool!

    Some SDIO links:

    http://www.wisegeek.com/what-is-sdio.htm
    http://www.sdcard.org/about/sdio/
    http://en.wikipedia.org/wiki/Secure_Digital_card#SDIO

    I'd like to use my HP50G as an answering machine;
    will it be able to play my calls back on its speaker?

    If not, is there an SDIO speaker card? ;-)

    -[ ]-

  9. Re: Connection limitations on the 50g

    On Jul 18, 2:38*pm, Robert Tiismus wrote:
    > Eric Rechlin kirjutas:> wrote:


    > For what it's worth: 50g has one more communication port! I read from
    > somewhere, probably from comp.sys.hp48 discussion, that 50g has full
    > blown SDIO hardware. The problem: no driver to use this functionality
    > * *If the SDIO would work then one could use SDIO bluetooth, SDIO WiFi,
    > SDIO whatever. And of course, this is unconfirmed...


    It would be nice if someone could confirm this. Given how old the 49g
    +/50g platform is (circa 2003) and the cost to license SDIO, I doubt
    it. My 2004 Sharp Zaurus has the same problem, no SDIO support, the
    reason given was license costs and the protection of intellectual
    property.

    A hacked EyeFi however may provide a 50g route to WiFi. EyeFi
    unhacked in a 50g could probably transmit files ending in an image
    format extension. EyeFi does not use SDIO.

    EyeFi hacking: http://dave-hansen.blogspot.com/



  10. Re: Connection limitations on the 50g

    On Jul 18, 2:11*pm, "Eric Rechlin" wrote:

    > The 50g was not designed to act as a USB host...


    I would also add that a USB host may be expected to provide power (5V,
    2mA - 500mA). I do not think the 50g was designed with that in mind.
    (I'll have to butcher a cable to see if I can get any power out of the
    USB port).

    > If you want to connect to other devices, use the RS-232 serial port. *Most
    > serial devices that you would be likely to communicate with have their
    > protocol documented, so it should be as simple as reading the documentation
    > and using the XMIT and SRECV commands appropriately.


    I have had lots of success with my 48GX and 50g serial
    communications. However I have had issues too. E.g. I was unable to
    control the X10 Firecracker with my 50g because it does not provide
    RTS/CTS lines or the commands to control them. X10 uses RTS/CTS
    toggling to send bits (this was done to allow the Firecracker to be an
    inline serial device). I was however able to control it with a 41CX,
    so that became my hand held home automation platform. Details:
    http://www.hpmuseum.org/cgi-sys/cgiw...s.cgi?read=763

    The original poster stated interest in "a USB ethernet adapter".
    There are serial to Ethernet adapters. The are called serial or
    terminal servers. You can get a used uni-port serial server on eBay
    for $10 (I see one now for $8).

    To Eric,

    Thanks for my 50g serial cable, it was a badly needed accessory. Now,
    can you make me a Bluetooth device? I have battery powered BT dongles
    now, but its a bit cumbersome to attach to a long serial cable. I'm
    thinking something small that sticks out of the serial port and
    possibly gets power from the USB port, or uses a small battery.
    Thanks.

  11. Re: Connection limitations on the 50g

    On Jul 18, 5:39*pm, "dataj...@gmail.com" wrote:
    > On Jul 18, 2:38*pm, Robert Tiismus wrote:
    >
    > > Eric Rechlin kirjutas:> wrote:
    > > For what it's worth: 50g has one more communication port! I read from
    > > somewhere, probably from comp.sys.hp48 discussion, that 50g has full
    > > blown SDIO hardware. The problem: no driver to use this functionality
    > > * *If the SDIO would work then one could use SDIO bluetooth, SDIO WiFi,
    > > SDIO whatever. And of course, this is unconfirmed...

    >
    > It would be nice if someone could confirm this. *Given how old the 49g
    > +/50g platform is (circa 2003) and the cost to license SDIO, I doubt
    > it. *My 2004 Sharp Zaurus has the same problem, no SDIO support, the
    > reason given was license costs and the protection of intellectual
    > property.
    >
    > A hacked EyeFi however may provide a 50g route to WiFi. *EyeFi
    > unhacked in a 50g could probably transmit files ending in an image
    > format extension. *EyeFi does not use SDIO.
    >
    > EyeFi hacking: *http://dave-hansen.blogspot.com/


    I was about to say something about remembering those EyeFis having a
    very limited distance (read about it in PC World when they came out),
    but checking out the website (www.eye.fi) they apparently have a range
    of 45 feet (indoors) to 90 feet (outdoors). Fantastic.

  12. Re: Connection limitations on the 50g

    On Jul 18, 12:32*pm, thatcad...@gmail.com wrote:
    > I'm kind of newbie to the 50g (and hp calculators in general, for that
    > matter), but am kind of psyched about messing around with HPGCC as I
    > already know C/C++ fairly well.


    All your questions can be answered from the Samsung manual for the ARM
    controller in the calculator. You can search for it, the chip is a
    S3C2410. The manual shows all the details about the UART, SDIO
    controller and USB controller.

    >
    > Anyway, my question, which may have already been answered some time
    > ago (can't find any straight answers though, so) is what are the
    > limitations of the onboard communications on the 50g? I know the
    > calculator can use Kermit and XMODEM, and that pretty spectacular
    > things have been done so far (Usinagaz). I'm interested in using
    > either the RS232 serial port or the USB port to connect to other
    > devices and ultimately collect data from them or control them, i.e. a
    > PLC, a USB ethernet adapter, surveying equipment, etc. I'm not at all
    > interested in using IrDA.


    From C, you can directly control the RS232 port, but nobody has ever
    written any serious library to do it, so you are on your own there.
    Same thing can be said about USB. In theory you can implement both a
    device or a host, but noone has ever done it. The USB controller is
    OHCI compliant, so you could (again, in theory) port an OHCI driver
    from Linux or other platforms to the 50G. The USB host power is not an
    issue if you connect the HP to a self-powered USB hub (once more,
    theoretically speaking). So, once you write an OHCI driver + and USBD
    driver + a driver for whatever device you connect, you'll be ready to
    go... :-) It's quite a challenge, no doubt, but if you are willing to
    try...
    SDIO is also a very feasible possibility, perhaps easier than USB, but
    requires a lot of effort and custom drivers for your devices too.

    FYI, there are boards out there using the exact same processor, with a
    working Linux OS. Porting efforts should be very little if you can get
    your hands on the sources of Linux embedded...

    For instance, something like this is really no different from a 50G...

    http://www.littlechips.com/sbc_main.htm

    So, if you want to have fun with the low-level programming, there's a
    huge playground for you. If you want a ready-made high-level API, you
    are out of luck.

    Regards,
    Claudio

  13. Re: Connection limitations on the 50g

    On Jul 18, 4:57*pm, "John H Meyers" wrote:
    <...>

    >
    > I'd like to use my HP50G as an answering machine;
    > will it be able to play my calls back on its speaker?


    Actually, manjo was able to play music on the calculator, and I have
    an unfinished and unreleased sound system that can do FM synthesis and
    play arbitrary 8-bit mono wave files (written in C). Watch your jokes,
    they may become real one day, haha!

    Claudio

  14. Re: Connection limitations on the 50g

    On Jul 19, 12:15*pm, Claudio Lapilli wrote:
    > On Jul 18, 4:57*pm, "John H Meyers" wrote:
    > <...>
    >
    >
    >
    > > I'd like to use my HP50G as an answering machine;
    > > will it be able to play my calls back on its speaker?

    >
    > Actually, manjo was able to play music on the calculator, and I have
    > an unfinished and unreleased sound system that can do FM synthesis and
    > play arbitrary 8-bit mono wave files (written in C). Watch your jokes,
    > they may become real one day, haha!
    >
    > Claudio


    manjo's site has a "soundcheck" proof of concept of PCM that runs on
    the 49G+, but is somewhat limited,
    and is certainly not full blown fm synthesis. But it does prove that
    voice playback is definitely not completely impossible.



  15. Re: Connection limitations on the 50g

    On Fri, 18 Jul 2008 16:39:31 -0500:

    > Given how old the 49g +/50g platform is (circa 2003)
    > and the cost to license SDIO, I doubt it.


    > My 2004 Sharp Zaurus has the same problem, no SDIO support,
    > the reason given was license costs
    > and the protection of intellectual property.


    The use of an SD socket to implement other sorts of devices
    seems somehow parallel to the earlier use
    of Compact Flash (CF) sockets in PDAs,
    to plug in various other things,
    such as modems and ethernet adapters.

    It would satisfy my idle curiousity to know any more
    about whether implementing other devices as an "SD card"
    is in any way related to doing the same as a "CF card"?

    > A hacked EyeFi however may provide a 50g route to WiFi.
    > EyeFi unhacked in a 50g could probably transmit files
    > ending in an image format extension. EyeFi does not use SDIO.


    Here are Eye-Fi Cards on sale, and a suggestion
    that said card can also be used with
    a Compact Flash Type II CF Adapter,
    which seems somehow again
    to connect the two socket forms (CF and SD)
    which originally emulated only disks:

    http://www.amazon.com/Eye-Fi-Card-Wi.../dp/B000X27XDC

    "Curiouser and curiouser"
    http://www.ruthannzaroff.com/wonderland/curiouser.htm
    http://www.curiouser.co.uk/

    -[ ]-

  16. Re: Connection limitations on the 50g

    "Claudio Lapilli" wrote in message
    news:d55d57b6-14c7-4b28-8989-1a8215b6dfe0@i76g2000hsf.googlegroups.com...
    On Jul 18, 12:32 pm, thatcad...@gmail.com wrote:
    X
    All your questions can be answered from the Samsung manual for the ARM
    controller in the calculator. You can search for it, the chip is a
    S3C2410. The manual shows all the details about the UART, SDIO
    controller and USB controller.
    X
    After reading this thread I cannot think anything but
    that the emulator should be fitted into a working iPAQ
    BUT with a twist: a real calculator keyboard

    I'm now restricting subject to WinCE based small PDAs
    since some PDAs do have an alphabetic keyboard
    one could "just" bring in a keyboard overlay
    then yet again with VGA resolution and a touch screen who cares?! :-D
    =========================
    Qonos style machine could be in several levels
    (remember the emulator)
    1) full blown Linux developer system
    available with a 16GB internal Flash (ala Nokia phones)
    also with 2*SDIO, USB, BT, WiFi, GPS, phone, camera

    2) A simple Linux user system with less options
    like leaving out the huge Flash, GPS, phone, camera

    3) Even simpler system, but still having Linux

    4) Emulator only very basic system for poor students
    ==========================
    Third option would be using phone OS
    and offering an emulator there

    To me the WinCE sounds best fit for HP
    but the Linux suits better for developers
    so on the long run it would be cheaper
    and not controlled by M$
    AND the software would follow

    What do you think?
    --
    Brother-Peter

    PS: Ultra Wide Band might be a future solution to BT problems
    power consumption, speed/power/range, etc
    time will tell
    also note that Flash is getting cheaper
    AND some competing technologies are emerging
    again getting rid of the limitations of Flash



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