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can someone help me connect a Vacuum Florescent Display to an arduino or my computer? Answered

I recently bought a Vacuum Florescent Display from a local surplus store and I'm working to see if I can control it with anything (i.e. arduino, computer etc.). It has a test/demo pin that you pull low to run some random stuff. I have although run across some old things were people attempted to do the same thing but I don't quite understand what they were talking about(http://sites.google.com/site/whitej/arduinoextras).

this link shows  some of the specs and such: http://technet.147120.com/wiki/index.php/Vacuum_Florescent_Display


The word is fluorescent.


True, but wee new whut wuz ment. It's better spelling than many questions...

It's one of those words that will eventually slip into dictionaries as an alternate spelling. Widespread not knowing the correct spelling would be a poor reason for that to be so.


As they say, it accepts an ASCII character stream for display, using the serial (RS232) protocol. A standard serial port should be able to talk to it, if you supply the right cable and configure the port for 19200 baud, 8 data bits, no parity, and 1 stop bit.

Or a library which can produce RS232 output on one of the Arduino's pins could be used, with the same parameters.

Looks like a nice basic text display, with support for a few simple cursor-control actions via control characters. Should be straightforward to connect and write data to.

When I first saw the dispay version of this I loved the bright blue-ish teal color it had.

But is there a library for arduino that can do this?

If not, it wouldn't be hard to write. As I say, it's straight serial output, and I'm sure that's available.

thanks for your help I actually got it to work with my arduino I am using the source code on http://sites.google.com/site/whitej/arduinoextras except I changed the baud rate to 19200.

Now all you need is a good project to use it in.


6 years ago

MAXIM makes ICs for bidirectional RS232 communication that develop their
own driver voltages from 5VDC
But your display only wants to receive, So you only need a resistor and
a TO-92 mosfet......   A


thanks for your help I actually got it to work with my arduino I am using the source code on http://sites.google.com/site/whitej/arduinoextras except I changed the baud rate to 19200.

so this should work? because I have read more into rs232 and I've read that the logic varies from positive to negative to get the 1's and 0's instead of high or low like the arduino(I've learned this is TTL)

The MOSFET driver also inverts the signal -- a logic 1 (a couple of volts) on the input turns on the MOSFET, which pulls the output down to (near) 0V, while a logic 0 (0V) turns off the MOSFET and the resistor pulls the output up to (near) 12V.

In other words, we've just recreated the RTL inverter gate. Add another input to it so either of two inputs can turn the MOSFET on, and you have a NOR gate. And once you have NOR gates, you can (inefficiently) build any digital circuit you want.

And if you ever wondered why PC power supplies have a +12V rail, RS232 ports are one reason.

That and the old RAM boards, I remember the massive 16K word RAM I got
for my Cromemco whey back when.


I'm trying very hard not to digress into the inevitable oldest-hardware thread...

Curious I am about what is this oldest-hardware thread anyhow ??

BYTE8406 principle: Any extended online discussion will eventually fall into a digression over "oh, yeah? Well, the oldest/clunkiest system I've ever worked with is..."

(The principle is named after a discussion of rumors in a particular issue of Byte about a new machine from IBM -- which turned out to be the PC-AT, I think -- and was hijacked by an enthusiastic but off-topic band of old-timers. I was one of them. It's often a fun topic, but it's an invasive weed and shouldn't be allowed to take root everywhere.)

Might (or might not) be worth trying it just at logic level. Some objects which claim to want RS232 in are actually reasonably happy with 5V, or even less.

(I haven't checked the spec on this one, so this is speculation, not recommendation. MOSFET-and-resistor driver is certainly cheap enough.)

I get away with that now and then, be sure to invert the RS232 logic
High becomes Low becomes a high then.


6 years ago

Whatever the voltage of your uP say 5VDC.
A logic 1 is also a high is also in the range of 3.5V to 5V.
A logic 0 is also a low is also in the range of 0V to 2.5V.
See a BIT trace of the character "C" Left to Right.................... A