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Help Wanted with 8x8 LED Matrix Alpha-numberic Morse-code Display w/ sound

Thu, 2012-04-26 14:51 — Huck

The IDEA is this:

taking an 8x8 LED Matrix... having it display a letter in a 5x5 section of the display(top left corner lets say) then displaying below it the corresponding Morse-code - . - where 2 leds == a dash, 1 led == a dot, and then a blank led to separate each dash/dot... then hooking up a small speaker to out put the Morse-code audibly...and scroll through the alphabet and digits 0-9 prefer using a Teensy as it would make a nice smallish package :)

Really just need help with how to write the sketch to display the different parts together all at once...

--Huck

Comments

Wed, 2012-05-02 22:36 — Camo

I would post this on the

I would post this on the mailing list for maximum win, or just take what you have to the meeting.

In the meantime, I think the trick is to use a few functions that does something like this: (psudocode) void displayLetter( char letter ) { 

  ...do something;
}

void makeBeep( char letter ) { 

   ...make some beeps;
}

and then in your loop function, make an array of the the things you want to output and iterate through the list calling displayLetter and makeBeep.

HTH.

Thu, 2012-05-03 05:12 — paul

I'll help at the meetup on

I'll help at the meetup on Monday.

Fri, 2012-06-01 08:15 — DeadProjX

An example of how I did the matrix

I'm certainly a n00b myself... but here is a link to how I accomplished the matrix to do something similar to what you desire. Basically you would create values for the different morse code equivalent's like i have for the eye movements... and then just execute the function. There are probably way smoother methods others have tried, this was my first attempt at something like this.

As for the tone, that should be easy enough, there are lots of tutorials on powering an 8ohm .25w speaker.

Real Blink App

I know size was a factor in your goal here... And this 8x8 matrix requires a decent set of pins. I would suggest maybe using a smaller Atmel chip like the ATTINY85/84 to lower your footprint on the MCU... But the Mhz it runs (8vs16) at may make the POV for the LED display a little less appealing. There is some info on the same site regarding other chips like the attiny45 and attiny2313 if it helps.

Good luck, learning the code is becoming a lost art! Any attempt to learn it is a worthwhile pursuit in my opinion!

Tue, 2012-08-14 20:37 — Huck

3-months later..

I've got the code finally going, to display the capital letter, and the last two rows display the morse code..

byte Q[8][8] = {
{0,1,1,0,0,0,0,0},
{1,0,0,1,0,0,0,0},
{1,0,0,1,0,0,0,0},
{1,0,1,1,0,0,0,0},
{0,1,1,1,0,0,0,0},
{0,0,0,0,1,0,0,0},
{1,1,0,1,1,0,1,1},
{0,0,0,0,0,1,0,0}};

that's what a letter looks like... now for my more ambitious desire... to have it BEEP the morse-code and flash a single led(not on the 8x8 matrix) in cadence with the dash, dash, dot, dash stuff...
but I can't grasp how to go about that since in order to display the code on the matrix it requires running a loop fast enough for the POV to be visible rather than blinky on the matrix.

any hints into where/how I aught to do this?

btw.. nifty blinking eye!