sending digits through serial??? Please help

[scarf1988]

Well the thing is that this homework is not at a huge hard level so it's pretty easy to do what he asked me to do. It can't be that hard because then the homework would be hard and i have like 3-4 days to make it work. the simplest solution is the one im looking for. i wanted to know if i use... i don;t know... some array led's in the labview window that are conected to the knob and if i turn it and the led shows that number if it will work on the boxing itself.

[SteveChandler]

Looking at the picture it looks like it must be using a line on the parallel port for each segment and two lines for selecting the digit. If that is correct then there is no simple or hard way to make it work - there is only one way.

Did your instructor just give you the display with no documentation? Is there a schematic or anything like a subvi that came with it?

[scarf1988]

No, he just gave it to me and said "make it work" :)) i know that the level of knoledge necesary for this thing is pretty low, because he didn't teach us that many things about labview so that's why i said that it's not very hard...

[RavensFan]

My concern is that he didn't even give you enough information to be able to get started.  Actually, he gave you outright wrong information.

He tells you to use the serial port, and that a USB to serial port converter works with it.  But now the indication is that it might actually be intended to connect to a parallel port.

Without correct information, you aren't going to be able to make it work.  And you could possibly damage the device or even your computer with the wrong information.

[SteveChandler]

scarff, make sure you let us know what the final outcome was.

[ajmartin]

Scarf,

Think about this for a moment,  it takes 7 digital lines to turn on all 7 segments of ONE of your seven segment displays. That would light up all seven segments and display the number eight on ONE of your displays. Since you say you want to do  this with a serial port, that means sending data down ONE line of the port, that is what serial IS one line for Transmit Data. So how do you get that one line to communicate with all 7 on your display? You would need a device with a UART ( Universal Asynchronous Receiver Transmitter) either attached or built in to it. Then that device would have to be connected to a BCD (binary coded decimal) or Decimal to 7 segment decoder driver. Then you would still have to multiplex between the two 7 segment displays. OR you could hook up a Microcontroller with a built in UART (Atmel AVR-ATMEGA16 is only about $2.95) and do the serial to 7 segment decoding in Software, the MEGA16 also has enough I/O lines to drive both displays at once. ( you need to learn some "C" though) (AVR FREAKS has a great forum to help with this!) After you get that wired , just drop a Knob on the LAbVIEW front Panel, find the control on the block diagram, open a COM port, code in the number of data, stop bits, and pairity  (probably 8,1, and , none for the AVR) and you are almost there!

So if all this seems EASY then yes this is an easy home work assignment.

Alan

[scarf1988]

Im going to him tomorow and see what he has to say about these things. The thing is that he said that it's an easy assigment, and i really believed him, so i guess that just by dragging the knob in the LabView screen and turning it will not work. Does the LabView library has a thing like these? Even if i doesn't work maybe i can see how i should do that by using some led's or something. Getting the idea might help me, and if it does how would it be called? :-?

[SteveChandler]

What kind of class is this? Software, basic electronics? I want to know how much help I should give you

[scarf1988]

well, it's a software class, he made that box and thoes screns, and every piece in the box so it's only a software class, that's all i have to do, the software for it...

[ajmartin]

Did you ask the teacher how to work this "box"?

Alan