Demultiplexing + pduino...how?

Robotland

hey

I have successfully setup a demultiplexer (4051), I can alternate between LED 1-8 by sending binary values to Digital out pin 2,3,4 and sending the actual signal to Digital out pin 13.

This works fine with the playground tutorial
( http://www.arduino.cc/playground/Learning/4051 ), however, I can not get it to work correctly with PD using pduino, I managed to control some of the leds but I didn't actually know what I did

I haven't found any good tutorials for the demultiplexing part in PD yet, so help would be very appreciated on how to easily select led 1-8 from PD with a demultiplexer.

Thanks

terrordata

Oh man!
i have the exact same problem!
iv been sitting with this for some weeks now.
please can somebody help us?
any suggestions are valuable.

obiwannabe

I don't have an Arduino board so this is just a crazy guess:

The 4051 doesn't have latching outputs, so unless you are writing in a loop over and over the output will disappear almost instantly. An octal latch like 74C373 might do the trick to hold the data.

wahtak

I havn't used PDuino but i'll try to help.

All you need to do is convert a decimal (in this case 0 to into a 3 digit binary number (for pin 0, 1 and 2)

[x\ number (or hradio) as input
|\
| [mod 2]
| \
| pin 0
[/2]
|
_
|\
| [mod 2]
| \
| pin 1
[/2]
|
_
\
[mod 2]
\
pin 2

Did that help?

Alex

EDIT: mixed up the pin numbers__

Robotland

Thanks for the help wahtak, the decimal to binary thing makes life a little bit easier now, however, I'm not sure you should send the the info as lists or not to the arduino interface...and in which mode I should trigger LED on pin 13.

Anyone got some clues perhaps?

terrordata

i still havnt figured this out either.
please help!

konsumer

I don't have a 4051 on hand to test, but the attached patches should work for input and output.

triggering pin 13 (led) is optional. They do it in the example to show you that the code is initialized. In my puredata example, I do the same.

For most things you can translate the examples pretty directly, so "pinMode 3" is the same as what you send to the arduino object. "digitalWrite(13, HIGH)" is "digital 13 1" in puredata. I'm doing the loop in puredata with metro and mod8 to loop through all the inputs, and converting them to 3-digit binary. On output, I'm just packing the address with the slider data (no loop needed.)

In this example, wire your 4051 up like this:

MULTPILEXED ANALOG INPUT

[pot] [pot] [pot] [pot] [pot] [pot] [pot] [pot]
  |     |     |     |     |     |     |     |
 y0    y1    y2    y3    y4    y5    y6    y7
  |     |     |     |     |     |     |     |
 --------------------------------------------  
|                                            |
|                   4051                     |
|                                            |
 --------------------------------------------  
  |     |     |     |
 s0    s1    s2     z
  |     |     |     |
  |     |     |     |
 d2    d3    d4    a0
  |     |     |     |
 --------------------------------------------  
|                                            |
|                   ARDUINO                  |
|                                            |
 --------------------------------------------

DEMULTPILEXED ANALOG OUTPUT

[led] [led] [led] [led] [led] [led] [led] [led]
  |     |     |     |     |     |     |     |
 y0    y1    y2    y3    y4    y5    y6    y7
  |     |     |     |     |     |     |     |
 --------------------------------------------  
|                                            |
|                   4051                     |
|                                            |
 --------------------------------------------  
  |     |     |     |
 s0    s1    s2     z
  |     |     |     |
  |     |     |     |
 d2    d3    d4    d5 (PWM)
  |     |     |     |
 --------------------------------------------  
|                                            |
|                   ARDUINO                  |
|                                            |
 --------------------------------------------

http://www.pdpatchrepo.info/hurleur/demultiplex_arduino_4051_input.pd

konsumer