EASYPIC4 Board Giveaway

[rmteo]

I have one of these that I no longer need (no GLCD). We can do another contest similar to the last one.

Walter, do you want to administer this one as well?

[rmteo]

The objective of the contest is pretty simple - to pulse/blink a minimum 4 LEDs (more is better) at independent, variable rates using any PIC of your choice. The actual blink rate is not important, as long as it is visually discernible. Also, the method to adjust the blink rate is unimportant - you can use POTs on ADC channels or whatever method you want.

Sounds easy? There's a small catch though - each LED must ramp-up and ramp-down in brightness from 0 to 100% and NOT just toggle hard-on and hard-off.

[cncmachineguy]

RMTEO, Hats off to you this is very generous.

Now I realize this new contest hasn't been approved yet, but I have 1 question. Should the intensity change with each blink, ie each LED will need to blink 200 times to go through the full ramp up/ramp down?

This is a very good contest idea. Thank you!! (did I mention I love puzzles?)

[rmteo]

The blink rate/frequency has to be adjustable for each of the LEDs. For every blink, each LED should ramp from 0-100-0% brightness. Perhaps this video of 2 LEDs will give you a better idea (note that the blink rate is different for each LED).

[mackrackit]

Blinky ideas??
http://www.picbasic.co.uk/forum/show...47&pagenumber=

[rmteo]

Blinky ideas??
http://www.picbasic.co.uk/forum/show...47&pagenumber=

Unfortunately, none of those ideas will qualify - they are just simple ON/OFF blinkies. Take a look at the attached drawing. The horizontal axis is time and represents the blink rate. The vertical axis is the LED brightness. The post that you linked to is like the upper trace. What I am looking for (as in the video above) is shown in the lower trace.

Also, the blink rate (or period) needs to be adjustable by some method of your choice. A minimum of 4 LEDs/channels are required. The blink rate of each LED needs to be adjustable independently and should not affect any of the other channels.

[rmteo]

Hopefully senior members (who may not wish to participate in the contest) will chime in with tips/tricks and/or code snippets to help the less experienced get started.

[ScaleRobotics]

Walter, do you want to administer this one as well?

Seems like you are doing a fine job rmteo, and great challenge! If you still want help, let me know, I would be happy to.

Is Mibam allowed, or is that cheating? http://www.picbasic.co.uk/forum/cont...-Modulation%29 .

[rmteo]

Thanks for your offer. I will handle it for now. You could move this to a more appropriate forum if you think it should be.

Any technique (including MIBAM) is good.

[rmteo]

Feel free to ask questions or to have any points clarified.

[rmteo]

....Should the intensity change with each blink, ie each LED will need to blink 200 times to go through the full ramp up/ramp down?

This is a very good contest idea. Thank you!! (did I mention I love puzzles?)

How is the puzzle solving coming along? Getting close yet?

[rmteo]

...Is Mibam allowed, or is that cheating? http://www.picbasic.co.uk/forum/cont...-Modulation%29 .

Were you able to do it using MIBAM?

[cncmachineguy]

Is this a first valid answer wins contest, or post and vote.

[ScaleRobotics]

Were you able to do it using MIBAM?

Thanks rmteo. My question was more to hint at a possible solution for others, and to get a scope of the rules. You have laid out two nice possible paths to get it done.

[rmteo]

Is this a first valid answer wins contest, or post and vote.

The person to come up with a working solution first wins - NO voting this time. The end date will be 30th April, 2011.

You want to start posting about your potential solution as early as possible as it may affect the final outcome. Good luck and have fun!!!

[cncmachineguy]

How is the puzzle solving coming along? Getting close yet?

The puzzle is coming along fine, I have it on a slow simmer.

Right now I am trying to decide on min and max frequencies. I am thinking .5 to 1000 Hz. But clearly 1K will look just full on, so I may go with 500hZ. Anything less then .5hZ will just be painful to watch.

Also trying to work out resolution for the frequency. Seems like it should not be linear with the pot adjust.

[rmteo]

Some pointers to take note of:

1. The variable/controllable blink rate should range from about 0.5Hz to no more than 8Hz - anything faster will appear as a flicker, which you do not want.

2. As the LED goes from full OFF to full ON and back to full OFF, its brightness has to be varied using some kind pulse modulation such as PWM or MIBAM. The frequency of this modulation has to be high enough that there is no flickering as the LEDs pulsate. Refer to the video and especially the drawing posted previously.

In essence, each of the LEDs is being driven by 2 modulated signals at the same time. A low frequency one from 0.5-8Hz which is the blink rate and a higher frequency one that controls the 0-100-0% percent brightness ramp which gives the LEDs a pulsating effect - instead of just going OFF-ON-OFF.

Hint: Think FM.

[cncmachineguy]

Thanks for the more refined parameters. This should help us all. It at least helps me to not have to decide on the spread.

The hint is very nice, thank you. I guess my solution is that, but haven't thought about FM since college. As soon as I could get away from analog I did. Guess thats why I am a machinists. LOL

[rmteo]

I hope I have not confused you (or anyone else) with these explanations. Trying to put the concept into layman's terms is lot trickier than I thought. In technical terms the objective is:

To create 4 independently controllable, low frequency (0.5-8Hz) channels of analog signals (triangle waveform in this case) using digital modulation (such as PWM) with the LED's acting as a low-pass filter.

Now that sounds a lot easier to do, doesn't it?

[cncmachineguy]

Well actually I thought it was fine before.

[rmteo]

Bert, have you made progress? Looks like no one else (besides Walter and yourself) has a solution for this contest. Do you (Walter, or anyone else) feel that perhaps it is too difficult and the contest should be changed to something simpler?

[cncmachineguy]

PM sent

[larryvc]

Anything less then .5hZ will just be painful to watch.

I might fall asleep watching at that rate. Working on ideas.

Hi rmteo.

[larryvc]

Bert, have you made progress? Looks like no one else (besides Walter and yourself) has a solution for this contest. Do you (Walter, or anyone else) feel that perhaps it is too difficult and the contest should be changed to something simpler?

rmteo,

From a mutual friend (mathematical place holder) on another forum:

What you kidding me? it's not rocket science.

[rmteo]

Four days to go - and it looks like there may be only one entry.

[Demon]

I just saw this contest now.


<---- darn tag under my name...

That is a very nice experiment board. I've been using the Lab X1 lately.

[rmteo]

I thought the GLCD was misplaced but I found it so the development board is like in the 1st. post. It comes with a PIC18F4620 - you can use any PIC16F or PIC18F in 40, 28, 20, 18, 14 and 8 pin DIP packages. I installed a ZIF socket in the 40-pin position.

If anyone is interested, I have a PDF of the manual (it is too large at 2.5MB to upload).

[cncmachineguy]

Oh! The prize gets even better. Is anyone working on this contest? I hate to see a great prize and contest not even attempted!

[rmteo]

Oh! The prize gets even better. Is anyone working on this contest? I hate to see a great prize and contest not even attempted!

Looks like nobody else, besides yourself, has any interest in this. So post your solution and lets see if you are the winner.

[cncmachineguy]

you have shamed me into it. LOL!

I am putting it together now, likely I will slide in just under the april 30 deadline.

[cncmachineguy]

Heres my code so far. It appears to work as needed, but thus far I have only tested it with a sim. I will try and put the hardware together tonight and test it in real time.

' Name        : RMTEO Contest 2.pbp
' Compiler    : PICBASIC PRO Compiler 2.6A
' Assembler   : MPASM
' Target PIC  : 16F1947
' Hardware    : RMTEO Contest
' Oscillator  : internal
' Keywords    :
' Description : PICBASIC PRO program to drive 4 LED's at independent speeds
' adjustable from 4 pot's. fade from 0-100-0% for each cycle
'
'
'
'
' Configure ports
'
'
ANSELA = %00001111  'port A 0-3 analog 4-7 digital
ANSELE = %00000000  'port E all digital
ANSELF = %00000000  'port F all digital
ANSELG = %00000000  'port G all digital
CM1CON0 = %00000000  'No comparaters
CM1CON1 = %00000000
CM2CON0 = %00000000
CM2CON1 = %00000000
 
' preload latches before setting direction
 
LATB = %00000000
LATC = %00000000
LATD = %00000000 'LED's 0 for red, 1 FOR GREEN should start red
LATF = %00000000 ' low nibble is drive enable. 1 disables
LATG = %00000000
 
' I/O direction
 
TRISA = %00001111'x,x,x,x,p3,p2,p1,p0
TRISB = %00000000'x,x,x,x,led3,led2,led1,led0
TRISC = %00000000'UNUSED
TRISD = %00000000'UNUSED
TRISE = %00000000'UNUSED
TRISF = %00000000'UNUSED
TRISG = %00000000'UNUSED
 
 
'REMOVE THIS LINE IF NOT SETTING THE CONFIGS IN CODE SPACE
 
@ __config _CONFIG1,_FOSC_INTOSC & _WDTE_OFF & _PWRTE_OFF & _MCLRE_OFF & _CP_OFF & _CPD_OFF & _BOREN_OFF & _CLKOUTEN_OFF & _IESO_OFF & _FCMEN_OFF
@ __config _CONFIG2,_WRT_OFF & _VCAPEN_OFF & _PLLEN_ON & _STVREN_OFF & _LVP_OFF ;_BORV_25
 
'------------------Internal osc setup
OSCCON = %11110000 'clock is 8 meg. turn on PLL for 32 meg clock
DEFINE OSC 32
DEFINE NO_CLRWDT 1
 
'Variables
 
'Port assignments     
 
'------------------port B
 
'---------------------words
freqs1  var word
freqs2  var word
freqs3  var word
freqs4  var word
freq1   var word
freq2   var word
freq3   var word
freq4   var word
 
'---------------------Bytes
TICKS   VAR BYTE
display VAR BYTE
duty1   VAR BYTE
duty2   VAR BYTE
duty3   VAR BYTE
duty4   VAR BYTE
myflags var byte
 
'---------------------Bits
 led1   var display.0
 led2   var display.1
 led3   var display.2
 led4   var display.3
 
 df1    var myflags.0
 df2    var myflags.1
 df3    var myflags.2
 df4    var myflags.3
'---------------------INIT VARIABLE VALUE
 
GOTO START
MYINIT:
BSR = 0
TICKS = 0
freqs1 = 128
freqs2 = 256
freqs3 = 512
freqs4 = 1023
duty1 = 0
duty2 = 0
duty3 = 0
duty4 = 0
display = 0
MYFLAGS = 0
 
'-------------------A/D setup
adcon0 = %00000001
adcon1 = %11100000
define ADC_BITS 10
 
'-------------------10uS interrupt setup
DEFINE INTHAND _TimeBase
PIR1.1 = 0
PIE1.1 = 1        ; Enable Timer2 interrupts
INTCON.6 = 1      ; enable PEIE
INTCON.7 = 1      ; enable GIE
T2CON = %00000100 ; Setup Timer2 AND SET PRESCALE TO 1:1. @32Mhz THE Interrupt
PR2 = 39'                 FOR TMR2 WILL BE 10uSec
RETURN
 
'---------------------start of program
START:
   GOSUB MYINIT
MAIN:
 
 adcin 0,freqs1   
'-------------------------led1 math
    if ticks>duty1 then
        led1 = 0
    else
        led1 = 1
    endif
    if freq1 > freqs1 then
        if df1 then 
            duty1=duty1+1
        else
            duty1=duty1-1
        endif
        if duty1=100 then df1=0
        if duty1=0 then df1 = 1
        freq1 = 1
    endif
 
 adcin 1,freqs2   
'------------------------led2 math
    if ticks>duty2 then
        led2 = 0
    else
        led2 = 1
    endif
    if freq2 > freqs2 then
        if df2 then 
            duty2=duty2+1
        else
            duty2=duty2-1
        endif
        if duty2=100 then df2=0
        if duty2=0 then df2 = 1
        freq2 = 1
    endif
 
adcin 2,freqs3
'------------------------led3 math
if ticks>duty3 then
        led3 = 0
    else
        led3 = 1
    endif
    if freq3 > freqs3 then
        if df3 then 
            duty3=duty3+1
        else
            duty3=duty3-1
        endif
        if duty3=100 then df3=0
        if duty3=0 then df3 = 1
        freq3 = 1
    endif
 
 adcin 3,freqs4   
'---------------------------led4 math
if ticks>duty4 then
        led4 = 0
    else
        led4 = 1
    endif
    if freq4 > freqs4 then
        if df4 then 
            duty4=duty4+1
        else
            duty4=duty4-1
        endif
        if duty4=100 then df4=0
        if duty4=0 then df4 = 1
        freq4 = 1
    endif
    GOTO MAIN
 
'-----------------------ISR
TimeBase:
    BSR = 0
    portb = display ' update led's
 
    freq1 = freq1 +1
    freq2 = freq2 +1
    freq3 = freq3 +1
    freq4 = freq4 +1
    if ticks >99 then
     ticks = 0
    else
     ticks = ticks+1
    endif
 
    pir1.1 = 0          ' clear interrupt
@ RETFIE

All comments welcome. I did this all software (no hardware PWM) as I thought it would be more fun.

Thanks for the contest RMTEO! Sorry I seem to be the only one entering.

[rmteo]

Yes, it will be interesting to see how it works!

[cncmachineguy]

Well I am done at work today, so home I go and hopefully get this put together and running.

Then to figure out about posting video - always something new and fun

[cncmachineguy]

OK, I have my working do-hicky video'ed. Anybody have any suggestions how to get it from my iphone4 to here?

I know how to upload it to facebook, but what good is that?

[ScaleRobotics]

If you can get it to youtube, that is probably the easiest way. Then add the link to your post, like this {video}your youtube link{/video} but with the other kind of brackets.

[cncmachineguy]

Oh dear. Guess it's time I learn to post on you tube now. I hope I figure it out before the deadline. Ok, I'll be back in a little bit.

[rmteo]

Don't worry about the deadline.

[cncmachineguy]

well you know, i have created the youtube account. sent the video to youtube via my phone. Now I just need to find the video on youtube. seems this part is the hardest.

[cncmachineguy]

I did it (I think)



whats better? getting my entry in or posting my first video? Hmmmm

[rmteo]

Looking at the video, it sure looks like you did it. Can you confirm that the drive to the LEDs looks similar like this (only two channels shown) - you don't have to make a video of the scope trace.