Here is a schematic for the shield:
http://mayhewlabs.com/media/Mux_Shield_Schematic.pdf

There are a lot of people asking questions about this board. Just thought I'd answer a few of them. The build quality here is superb. The wiring does allow you to write individual pins high/low or read analog/digital values from any pin. It uses the analog pins to write/read (1 pin for each muxer chip) and the digital pins to determine which chip you wish to write/read to/from. You cannot operate on 2 different pins on 2 different muxers at the same time. But you can operate on only one pin on one muxer at a time. Unfortunately, the muxer chips have no "latch". So once you change the operating pins, the value goes back low (for outputs). This shield is great example of expanding your gpio ports, but to be truly useful, we'd probably need a register or something on the other side of the muxers. That said, you could easily connect 6 shift registers with the available pins.

That's pretty sweet!

Hi, is it possible to use multiple Mux shields in parallel, to allow you to access 192 inputs and outputs?

Thanks! --Buz

How would I get this rotary encoder https://www.sparkfun.com/products/9117?

to work with this shield? I am trying to have 4 rotary encoder working with a few buttons.

Thank you,

Similar to esklar below, hoping to direct this to MarkMayhew but anyone who is willing to help me out I'd appreciate the advice. As Mark stated, the mux shield itself isn't suitable to drive servos, but if I run it through Adafruit's PWM driver on its own power supply, it should work and allow me to use multiple switches muxed to the Arduino, correct?

I'm playing with this board, using Mark Mayhew's examples.

When running as inputs, it's all good. But when I try to run the digital output example I get no voltage change on the output pins.

Has anyone experienced this? I'm using the latest 103 version of the IDE and tested with a Duemalouve as well as BlackWidow. No joy.

So far stumped - any hints/advice appreciated.

Thx,

brian...

I'm at a loss as to how you use this for both analog input and digital output at the same time. Do I use the individual 4067's separately in a sense? Can I have inputs and outputs on one individual 4067 at the same time? Code snippets would be helpful.

Thanks,FTM

I know this can be used as analog or digital but can you use it as both? I am working on a project right now where I need more digital and analog input/outputs. If so that would make it easier compared to my other options right now.

Hi! I have a project in which I need very many pins. Would this shield work with Arduino Leonardo? If yes, could it be stacked to it, or would I have to wire it another way? Thank you.

Is there a way to successfully send analogWrite PWM brightness pulses to 48 LEDs? When I try analogWrite instead of digitalWrite in the example digital out code, I (not surprisingly) get binary results, with the LEDs being fully on when the value is 128 or above and off when the value is 127 or below.

What is a good way to control the brightnesses of multiplexed LEDs?

Thanks!

Hi there! Can I use a Mux Shield to extend the 6 digital capacitive sensors? See http://arduino.cc/playground/Code/CapacitiveSensor

Below is the code I would need to modify:

DDRB &= pin; // input PORTB |= pin; // pullup on for(i = 0; i < 16; i++) if( (PINB & pin) ) break; ...

Can I use 2 Mux Shield in the same Arduino UNO?

I am starting a sensor network using 16 temperature sensors, 16 red LEDs and 16 blue LEDs.

I need one LED stay always ON (RED LED if the temperature is HIGH, until the state of the sensor change and turn ON the other LED(BLUE LED if the themperature is LOW).

I want to know if this Mux Shield can do somethig like this code writed in Arduino. (Not exactly as above but some kind like this):

void loop() {

int Value1 = digitalRead(Xport); //this is just for 1 sensor,

{

Serial.println(Value1); 
                            //this turns ON the red LED,if the  
                           //the temperature is HIGH
  if (Value1 == 1)         //and keep it HIGH until the sensor
                           //value change to 0 and turn off 
                           //this led and turn on the BLUE LED.
  digitalWrite(ledPinx, HIGH);
  else 
  digitalWrite(ledPinx, LOW);

  if (Value1 == 0) 
  digitalWrite(ledPinx, HIGH);
  else 
  digitalWrite(ledPinx, LOW);

  delay(300000);  // 5 minutes

}

I found also a video project for this shield: http://www.whatisarduino.org/bin/Hardware/Mux+Shield

Does this shield have any compatibility issues with Firmata? In other words, am I still able to read all 48 inputs into an external platform (i.e. Max/MSP, PureData, Isadora, etc.)?

Thanks in advance!

I just posted code to use this shield with the Netduino. http://forums.netduino.com/index.php?/topic/2975-mayhew-labs-muxshield-and-ti-74hc4067/

Does the Mux Shield fit the Arduino Uno?

I would love to buy this shield!! Any idea about when will be available again?

Hi, Im very new to this type of code. How am i able to set a single pin on the mux shield to HIGH or LOW? Thanks

Hi guys,
i'm really new to embedded electronics so I appologize for my newbish questions. I'm planning to use 3 mux shields with a teensy board and I have some questions to that board.
1. As i'm planning to use multiple boards on one teensy and each board will have its dedicated tasks ( 2 for digital in - 1 for analog in), do i have to make major changings to the example codes above?
2. My biggest concern is the latency. Does anybody have some expirience on how fast these boards/the code really is?
TIA
Elda

It makes sense, and I will take this way and look what happen. Thank you for your advice.

I am working with the Arduino Duemilanove ATMEGA 328, and I need to multiplex 96 temperature sensors. I am using 16 Arduino units and 6 temperature sensors are connected to each one. In this way I am covering the 96 sensors (16 x 6). So I want to connect the 16 Arduino to the multiplexer and have one unique output.
My consult is if the Mux Shield (sku: DEV-09832) work fine with the Arduino Duemilanove ATMEGA 328 into the details describe above. Thanks

I am pleased as punch that this shield exists, and doubly pleased by the red cardboard box on my desk containing it. The pins are a bit too short so the first 4 or 5 of the inputs all contact the USB housing. It needs longer pins. To compare it to the ethernet shield, the length of the pins on the mux shield are about as long unmated, as the exposed section of a fully mated ethernet shield. This is true on my Duemilnova and my Uno. As suggested I am going to pick up a Arduino Stackable Header Kit.

Built-in latching would be super-nice. I'd happily give up one more digital I/O pin if I could "set and forget" the 0/1 state of any of those 48 outputs.

It is a very good idea of developing this shield. Is it by chance that we could have access to the code of the MP3-Handrail described in the video?
Thank you in advance,
Cheers

This looks like a nice board, but I don't get how you can have 48 outputs without any latches?
Surely you can only have 16 stable OPs at any one time and if you do anything with the other 32 you lose thier state.

Rob

dgarcia42: I have another shield that is currently using digital pins 2, 3, and 4 - how difficult would it be to make this shield use pins 5,6,7 and 8 instead of 2,3,4 and 5?
It shouldn't be too hard. It might be possible that you can use pins 2-5 for both shields in an ingenuous way since the Mux Shield only uses these pins for control lines during an analog read (if your not in the middle of an analog read, it makes no difference how the lines are used or what data is on them). But, if you want to remove the conflict in hardware, here is how:
Cut the stackable header leads on the Mux Shield pins 2-5 so they don't connect to the Arduino. Run jumpers from pins 5-8 on the Mux Shield to pins 2-5 on the Mux Shield. Change the example code to the following:

define CONTROL0 8

define CONTROL1 7

define CONTROL2 6

define CONTROL3 5

This way you are isolating the Mux Shield from the Arduino and still getting the Mux Shield the data it needs.

I have another shield that is currently using digital pins 2, 3, and 4 - how difficult would it be to make this shield use pins 5,6,7 and 8 instead of 2,3,4 and 5?

can you split them up and use this for analog & digital at the same time?

Am I correct in inferring that, although there are 48 I/O ports, there are only 16 I/O port selections, so that you have to select ports as triads? For example, you can select ports 1, 17 and 33 simultaneously, but not any one of them without selecting the other two and none of them in combination with other ports. (I do realize that just because I've selected a port doesn't mean I have to read from or write to it.)
Also, how much current and what voltages can it handle? There are numerous "Vcc" ports, but I haven't found where it's specified to what they're connected. If it's the regulated 5 V from the Arduino, that'll limit the available current/port substantially. OTOH, if it's the Arduino's Vin, then it's not likely to be a very stable source. Furthermore, it appears it would be useful, for at least some applications (controlling servos, for example), to be able to provide power to the "Vcc" rails around, rather than through, the Arduino.
I'm thinking about the suitability of the Mux Shield to drive large numbers of servos. However, I have yet to do the math to determine how many servo control pulses I can fit in the time between pulses to a single servo.
TIA for you thoughts,
Eric

Will this fit on top of an ethernet shield? Most don't since the cat5 jack is so large.