connect basic stamp to hp 50g calculator
mklrobo
Posts: 420
I would appreciate any help in solving the connection from the basic stamp (bs2p) to the
hp 50 or 49 hp calculator. Direct rs-232 and usb does not work. Used usb to serial conversion
board, no effect. The rewards for doing this is great; the stamp gathers/controls data to/from
the calculator. The calculator can take data and extrordinary processing to perform diagnostic/control
commands. This "avatar" can be the perfect diagnostic tool, and possibilities unlimited!
Thanks for your help.
hp 50 or 49 hp calculator. Direct rs-232 and usb does not work. Used usb to serial conversion
board, no effect. The rewards for doing this is great; the stamp gathers/controls data to/from
the calculator. The calculator can take data and extrordinary processing to perform diagnostic/control
commands. This "avatar" can be the perfect diagnostic tool, and possibilities unlimited!
Thanks for your help.
Comments
It has an infrared, mini - USB, mini - serial. I have viewed output from the serial on my PC oscilloscope.
Tried to "hack" the data, running data match for used protocol. have not located one yet. I appreciate your
inquiry. This uses of this type of circuit will make the star trek tricoder look like a peanut whistle.
hp49/docs/misc/
in particular:
Universal Lab Interface Software Developer's Guide
It is probably 9600 baud with software handshake.
I don't know about signal polarity.
Duane J
have not used the protocol language in the link you indicated before. Look forward to
using it! Thanks again.
Can't find a document that explains all these.
the "tools" button. I have not been able to run a program from hpcalc.org, at this time. Hpcalc.org has alot of instructions
of the programming functionality of the calculator. When running a dedicated program, I assume, I will have to set
baud rate/protocols in the program. protocols in my 50g are Kermit and Xmodem. I think Xmodem is more user
friendly, mainly because it has been used so widspread, and is old as the hills. There was a basic stamp article
that let the stamp "talk" over an Xmodem dedicate chip. I will have to find that...? I appreciate your help.
Your work on this can be benificial to you... examples of uses - oscilloscope, spectoanalysis, robot control, Rapid
Math Model Integrator, and universal diagnostic tool. Cheaper than a laptop, with the power of Mathcad! excellent for
field repair uses. use on cars, printers, planes, trains, anything that requires electronic repair. Need another program
in the field? jsut download one from your home computer, or use an SD card, on the 50g!
Thanks again for your help!
it is clean. I will try to use the File transfer method to just send and recieve data through whatever
process that i can discover that will work. I will try to pass a letter or a number through first, back
and forth. If that works, larger data packets can be sent. There "should" be a common protocol
used, because, the hp50g can communicate to a computer via serial port. RS-232 and or IC2 is the electronic
protocol, and kermit and/or Xmodem is the data protocol, right? If so, the basic stamp must use a
common protocol to communicate with the computer. I would assume it would be the simplest one,
in order to NOT to consume physical memory on the main chip. - ?
Another fellow on the forum wants to use an HP-48 calculator's serial with Forth on the Propeller. To help out, I ordered a serial cable for my HP-50gx. But since I am in Taiwan and payment had to be sent by mail, I may not get it in less than 4 weeks.
I stated reading about the RS232 serial port on the HP and looking for configurtion items. But the documentation doesn't mention if there is any special handshaking protocol.
After a physical loopback test, you might try using a serial terminal program on a PC to snoop what it might be sending. And to try sending. That may save a lot of time as you won't have to write test code in the BasicStamp.
In fact, if you are using Windows... the Hp50g may have a Windows application that will at least confirm you have a useful communications link.
RealTerm will be a great help if you have to decode handshaking. And it is FREE.
There are a lot of Terminal Emulators with will provide Kermit and Xmodem support for free as well. Get these features running with a regular PC. The BasicStamp doesn't have a file transfer capablity and is rather bare bones. SO the work will be to slowly strip out the stuff that makes it complex.
http://realterm.sourceforge.net/
http://en.wikipedia.org/wiki/List_of_terminal_emulators
I.e.
Baud Rate: 300 to 38,400 baud (any rate in this range will work)
Word Length: 8 bits (8 data bits)
Parity: None
Stop Bits: 1
Handshake: X-on/X-off (<Ctrl>+Q/<Ctrl>+S)
Duane J
and they would not communicate. Only through the infrared. I ordered the cable for the 50g,
that was made by a private person. It did not work, and it was recommended by the 50g
software. I was hoping it would be plug and play, but there must be something more to it.
Once the data communication problem is solved, the rest will be simple.(I hope)
Good work! The solution seems to be close!
When we solve this problem, we can solve the communication problem for the HP 48 to the propeller. Solve one, solve both.
Thanks for your help.
infrared port. the infrared must (i assume) must be modulated before riding on the infrared.
Thanks.
Regarding Xmodem and Kermit, I avoid both of these in my Minicom configuration when I use the Propeller in Forth. Unless the connected device specifically wants a modem protocol, it would be likely that you want none.
Xon/Xoff might also be a feature that can be toggled on and off. I wonder if the 'server' selection on the HP calculator is really equivalent to a 'terminal' that sends output from the keyboard, and receives input to the display.
I am not certain that the Universal Lab Inferface serial specifications are as versitle as the HP-48,49,50. For example, I am sure I can get 115,200 baud. But what I can't get is a simple and clean explaination from HP on how to use the serial port. I have all teh original documentation for my HP-50gx, including a 848 page PDF. These guys loved to write, but it was all about the math functions. the programing modes, the display modes. and such. When it cam to i/o, they suggested you download a Windows package to work with the calculators i/o.
IOW, it seems they wanted to keep the whole interface proprietary and not allow generic hookups.
What little I have discovered is that the serial interface has 4 wire - ground, Tx, Rx, and V+.
The Tx and Rx are 3.3v logic signal that need to go through a MAX3232 to invert them for normal RS-232. But you can still do a loopback by jumping Tx to Rx directly and without a lot of external wiring.
The HP50g Advanced User's Reference - Edition 2. Go to the Index at the back of the 600 plus pages and see the section on serial communications.
It seems to apply to the HP48, HP49, and the HP50.
This is useful and stuff I was NOT aware of.
And a more direct link ... http://www.hpcalc.org/details.php?id=7141
is not matching(handshaking), it still will not work. I have had problems with the protocol matching, and so that is
why I had originally started "hacking" the data stream.
Also, take a look at the document on building your own serial cable.
Gawd, HP just makes things so complex.
You do realize that the BasicStamp2 is able to directly take inverted serial signals, don't you? And it might even handle the 3.3v logic directly.
library, and the processing power of the calculator. I would like to use any calculator that would fit the
solution, but which one is compatable, and has the raw processing power?
I will keep plugging along, to try to find the solution. TI is alot friendlier, but lacks the processing power.
verify protocols that match the documentation. Does anyone know what protocols the
bs2p stamp uses in IC2 and serial out mode?
I have weeks to wait for a cable, so at this point I really can't do much more to help you. Besides, I have an HP-50gx with updated firmware. I am not sure I can offer much real advise on the older versions.
I appreciate your help. If we can crack this problem, the rewards are great. I can program in
"C", so I am going to try to identify the protocol via live data train capture. Getting data to/from
calculator is going to be real trick. Once again, I appreciate your help in this daunting problem.
that. I bought the stamps for this purpose. Thanks.
serial or infrared. The infrared could be cleaner, and would allow an easier hookup, with no hardwire.
Thanks.
I suspect the IR in the HP calculator is IRDA. And that is intended to transfer blocks of data, often with file names. On the other hand, the BasicStamp is very much a character by character device.
Linux has an IRDA project that might help, but it is a lot more complex to do IRDA than it is to do either simple IR remote control or character-by-character transfers. The use of Kermit supports block-by-block data transfers.
http://irda.sourceforge.net/
http://www.lirc.org/
If you are developing your own code, starting with character-by-character transfers is best. Later you can learn about blocks as these require more computer resources. I am not sure that anyone has developed IRDA software for the Propeller. It won't work on the BasicStamp.
supply the correct data train time/sequence info. This would be a "buffer", to ensure that both devices are satisfied with
the data passed. This should stop possible data collisions, lost data, and unexpected "shifts" in the pulse train.
Wow, great info!
Awesome! The suggestion would give a specific purpose for the datalogger. Once the datalogger is designed for that specific calculator, it could be used for
a buffer for other similar purposes.
Since the data buffer will be needed, that would explain why other attempts failed. Unless there is a datalogger, correct data trasmission would be
problematic. Also may function as a "translator", and could be used with other calculators. This may offer a solution with the propeller problem you were involved with.
This really starts with a hack. And the two ways to do so seem to either attempt [a] a loopback, or set up an RS232 cable that is Y-cable to snoop the communications between a computer that works with the communication application software.
The RealTerm software would allow a second computer to snoop the dialog between the HP calculator and its application on a PC.
After you get some idea of how the exchanges are working, the way to get what you want will be a lot clearer.
I just can't do any of this until I get a cable for my HP-50gx, not even the loopback.
cool! If you do not recieve the cable, I have one that I bought, supposed to have worked, but did not. You can have it, (free),
although, like I say, I could not get it to work for me. Serial port of calculator to serial (9 pin) port to computer.
I will start on building the system, serial documentation on stamp, datalogger parameters and dedicated translater program,
and analyze the calculator's data train. I appreciate your help.
:cool: maybe the propeller is the chip to use for a datalogger/translater function. I will review the advantages of stamp/propeller in reference to the needed purpose. Thanks.