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As I can read on manuals and how I can see, a great limitation of the HP 42s calculator is that there is no way to input or output electronically interchanged files, so that I can't save or transfer a program from one HP 42s to another;
I must manually key it in every time......but sure there is no way through the IR port to chatch and save a listed program directed to the printer?
Excuse me if the question is maybe stupid and could be dead horse flogger matter
Cheers
Edited: 1 Sept 2012, 11:41 a.m.
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Use the Free42 emulator so you can read, write, and transfer programs to emulators on other machines and even share 41C-compatible programs with the HP-41CX emulator on TOS.
In fact, I often run complex programs on the free42 emulators where I can debug them (using the trace to printer feature). Once I get the program working fine, I then load it on the 41CX emulator. This approach has really helped with advanced applications that I have prepared for HHC2012.
Namir
Edited: 1 Sept 2012, 12:39 p.m.
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This still doesn't help with a physical 42S. The problem is that the IR LED is output only. You can capture the output, e. g. with a 48G, but you cannot reload it into anther 42S.
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I bought my 42S in 1989 and used it extensively, professionally, for over 5 years. Back in those days a programmable calculator was an important engineering tool.
But I don't recall ever running out of memory, nor having to reload by hand a program I had deleted. Because each program is named and can have its own menu, there wasn't any need to delete programs unless they really weren't used any more. The lack of an ability to input stored programs never caused me any grief.
The IR printer was important for documenting programs. I'd print the listings, tape them to a sheet of paper, then photocopy the paper since the thermal paper would fade over time.
Today, if one were to recreate the 42S, I think having an input capability would be very desirable. Not so much for backup and restore, but for sharing.
I still have my 42S and use it occasionally. It has a half dozen programs including one still there from 1990 that calculates Hohmann transfer parameters. Oddly enough I used that program a week ago when someone asked what would happen to a bullet if fired from a gun by an astronaut outside the Space Station.
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Quote:
… It has a half dozen programs including one still there from 1990 that calculates Hohmann transfer parameters. Oddly enough I used that program a week ago when someone asked what would happen to a bullet if fired from a gun by an astronaut outside the Space Station.
More interestingly, what was the effect on the astronaut, assuming that he/she was not anchored to the ISS? What was the caliber of the gun and the type of ammunition loaded, and in which direction relative to the orbital direction was the gun pointed when it was fired?
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>More interestingly, what was the effect on the astronaut
Arrested on return to earth for slipping a gun through the TSA. Obviously, the astronaut is a terrorist. New security measures to follow.
TW
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Quote:
>More interestingly, what was the effect on the astronaut
Arrested on return to earth for slipping a gun through the TSA. Obviously, the astronaut is a terrorist. New security measures to follow.
TW
The TSA wouldn't find the guns aboard the Space Station because they are Russian guns. Their presence isn't well publicized.
Last I heard they are three barreled shotguns designed to fire slugs, shot, or flares. And there's a machete in the stock. The guns are part of the survival package aboard the Soyuz.
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I don't think a gun would fire in a vacuum. Needs oxygen for the powder to burn.
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How do they fire under water then?
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How do they fire under water then?
Please note the Sojus capsules touch down on land - Russia is a target big enough ;-)
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OK just looked it up. Apparently MODERN gunpowder does have the oxydizer needed for the burn in the mixture already. It doesn't come from the atmosphere. Didn't know that...
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Quote:
OK just looked it up. Apparently MODERN gunpowder does have the oxydizer needed for the burn in the mixture already. It doesn't come from the atmosphere. Didn't know that...
Even the old blackpowder contained its own oxygen, in the form of Saltpeter (Potassium nitrate).
The only problem I can think of would be the extreme hot or cold temperatures, which might effect the reloading operation of an auto pistol. Or the modern polymer frame guns might soften up (they melt at just over 400 F) in the sunlight.
And as someone else mentioned, the recoil would cause the astronaut to rotate. I'll let someone else estimate how fast. Assume say, a 300 lb astronaut in suit, a 2 ft moment arm, 950 fps bullet, 230 grains, give or take (about 460 ft/lbs energy).
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Quote:
Today, if one were to recreate the 42S, I think having an input capability would be very desirable. Not so much for backup and restore, but for sharing.
Infact, the sharing pourpose I specially meant
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This still doesn't help with a physical 42S. The problem is that the IR LED is output only. You can capture the output, e. g. with a 48G, but you cannot reload it into anther 42S.
Not quite true. The diode is output only, but the IR serial line can be used as input channel, too. Several years ago Christoph Giesselink demonstrated serial INPUT and output using the IR line of an 28S (donated by me). The initial goal was to find out whether serial input was possible on the 42S. The 42S has a similar IR circuitry, and thus it should possible to input data through the serial IR line. AFAIR Christoph published a suitable paper, too.
However one has to enable access to the serial line by opening the calc and soldering wires to the IR serial line.
The software setup is a small transceiver program on the Saturn based calc, and a terminal program on the PC side.
Ray
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Oh, thanks Namir, I can use and in fact I'm enjoying too free emulators of the 42s, but actually my question was about the possibility to do it with real machines...
I don't understand why, after a "complete computing system" like the 41, the 42s was not equipped with a card reader device, even external (connected maybe with the IR port) or simply a interchangeable modules interface (all external, in way to keep the high pocketable size of this great calculator!
For which regards the emulators I found, playing today with a couple of them, that the one which use the dumped image is actually closer to the real calculator respect to others, I'm spending now few hours to compare real and different kinds of emulators features
Really I can say how is easy and fast to import with them programs already listed than to key them step by step........magical OS
Edited: 1 Sept 2012, 3:59 p.m.
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At the time the 42S was introduced, the answer was that if you needed a card reader or other I/O, you should buy a 41CX instead.
After the 41CX was discontinued, the answer was that you should buy a 48SX instead.
The 42S wasn't intended as an expandable calculator. It was a midrange scientific.
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Quote:
At the time the 42S was introduced, the answer was that if you needed a card reader or other I/O, you should buy a 41CX instead.
After the 41CX was discontinued, the answer was that you should buy a 48SX instead.
The 42S wasn't intended as an expandable calculator. It was a midrange scientific.
It's now clear, many thanks
What do you think, Eric, about the display contrast "issue" (see my previous post, please).
Ciao
Edited: 2 Sept 2012, 3:18 a.m.
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I don't really know. If you can read the LCD at all, it probably doesn't have the drive transistor problem.
LCD display technology from the late 1980s was definitely not as good as what we have now. Some LCD displays go bad over time, perhaps due to degradation of the LC material.
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