Linux on a cash register

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I got the LED-on-a-stick working, sorta. It's a really bright display (and not actually LED-based; it's vacuum flourescent). This pic was taken with a flash in a bright room. One problem: it's in Cyrillic, I think. Or Sanscrit. Thai? Might as well be Martian. I've been sending it all kinds of ASCII, hex, octal, whatever and can't seem to find out how to make it consistently display what I want.

I wrote a tiny perl script that sends sequential "data" to the serial port the LED-on-a-stick is connected to (and STDOUT) and waits for me to hit the spacebar. I figured that I could see the decimal, hex, octal, and ASCII (if applicable) value on the monitor and then look up and see what the display read. If I see that I just sent '6d' and the display says 'm', then I had something. However, results so far are not good.

Sometimes I send one value, and see one charter displayed. Sometimes I send a different value (in the same base) and I see the same value. Sometimes a value will display one character, sometimes more than one, sometimes none at all. I'm guessing that the display is expecting multibyte input: two or more characters, comprising at least one each printable and control, make up one displayed item. By item, I mean one readable character, one shift of the display, one symbol, one flashing symbol modifier, whatever. That would be one way to make a lot of display permutations with only 8 bits of input. Makes my job kinda time consuming, though, unless I can figure out how to get a return value from the display. So far no luck there. Heck, I don't even know what sort of port settings to use. I have email out to the company pleading for help; I guess I'll see how nice they are.

So my dream of stock quotes and weather and /usr/games/fortune and web-base user input and whatever showing up is on hold. Bummer. I'm just not that good with hardware-level stuff. I ended up redirecting syslog to the LED-on-a-stick out of spite, though. It was fun to see what a reboot did, but was otherwise unsatisfying.

In other news, I have the thermal printer working. I have Apache logging to it. 'Course, only I know the URL, so it doesn't print much, but I'm running out of paper. Trey says he has a lot of it, and he's sending me some (the stuff he has got has a warranty/return policy thing printed on the back, and while inappropriate for the store is very good for my uses). Turns the little unit is just about like any other printer, albeit a very small and very fast one. I haven't done anything very fancy (bitmap graphics, cutting the paper automatically, etc) with it but I will at some point. Probably when I give up on the LED-on-a-stick. Unlike my display pole, the printer came with a severely comprehensive manual, right down to sample BASIC programs to make it print/do various things. I might even take up BASIC again after a 21 year hiatus, just because I can.