QR Codes

[jerome ibanes]

Hello,

I was wondering if one knew of a way to generate QR-codes on the 82240b, or if this is even possible on such printer?

If so, it might be a nice way to backup a WP34+IR, HP-42 or else.

[John Ioannidis]

I don't see why not. Before you do any programming, I suggest you start by going to one of the web sites that let you generate QR codes, such as http://www.qrstuff.com/, copy the bits, and see if you can print it and have a readable result.

Generating a QR code requires a fair amount of computation and memory: even the smallest QR code is about 20x20 pixels, so you may or may not have enough processing power in a calculator to generate one.

The best open-source implementation I know of is from the ZXing ("Zebra crossing") project: http://code.google.com/p/zxing/

Let us know how it goes!

[Egan Ford]

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If so, it might be a nice way to backup a WP34+IR, HP-42 or else.

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Dunno about "nice". E.g. 'A'. there's 7 or 8 bits of data. The equivalent in QR would be 8 blocks + redundant data (just in case part of the QR is lost--redundancy is tunable) + markers for mobile phones and other capturing devices.

The largest QR codes (which I doubt the 82240B could produce in readable form) have relatively little data. At best, you get a URL out of it for use online (to get even more data :-).

I'd think a program listing would be 'nice' and for data, some type of ASCII dump.

Now I can think of other uses for a QR code generator on the 34 or 42. E.g. a program or a game that needs to send out for more visual data for the user that then uses that info for a prompt. E.g. an adventure game. You could have 1000s of URLs with content like pictures, sounds, and text. But the logic on the 34/42. When the calc needs to tell you a story or give you more data, you get a QR code. You then scan that with your phone, review the website, and move forward with the game on the 34/42.

My version of something similar for the Apple IIe computer:

http://asciiexpress.net/gameserver/gameserverclient.mp4

I found it easier and faster to pre-compute the QR codes. Generating QR codes on the 42 may take a very long time. 34, no problem.

If you really wanted to be annoying you could create an ad-based program that from time to time requires that you print out a QR code, go the web site where you'll be greeted with an ad and a code to continue using the program.

[jerome ibanes]

Do you think the QR code would fit in the WP-34s firmware itself, and that the WP-34s has enough available memory to generate them? If so, you're right, there might be more possible applications.

The idea, of course, is not to get the data out of the WP-34s only, it's to make it easily readable by webcam/scanner featured devices.

According to this document: http://blog.qr4.nl/page/QR-Code-Data-Capacity.aspx
a 25x25 QR code can hold 47 alphanumeric characters or 77 numeric ones, which is plenty.

[Egan Ford]

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Do you think the QR code would fit in the WP-34s firmware itself, and that the WP-34s has enough available memory to generate them? If so, you're right, there might be more possible applications.

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As a bit pattern, yes. Dunno about the QR coding.

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According to this document: http://blog.qr4.nl/page/QR-Code-Data-Capacity.aspx
a 25x25 QR code can hold 47 alphanumeric characters or 77 numeric ones, which is plenty.

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With the same 625 bits you can hold 89 7-bit characters using plaintext. Your OP was about using QR for backup. My point was that for backup, not practicable. But if 47/77 is all you need, well then, go for it.