Happy Tuesday, everyone! I tend to get excited about products that enable beginners to be really creative, and today’s product highlight is one I think is worth getting excited about!
A few things that I really like about the shield:

The shield is an add-on board that was designed to be used with the chipKIT Uno32, the uC32, or the Max 32.

Once you connect the Basic I/O Shield to the chipKIT board of choice and download MPIDE (referenced in the video), then a world of projects are instantly at your fingertips. This is because of all of features that are built-into the shield.

Perhaps the best part about the Basic I/O Shield is that you don’t have to spend time wiring up all of the individual components. This is great for teachers who have limited course time, if you are doing a workshop focused on the programming, or if you want to spend your time wiring up something non-traditional… like 12V Analog LEDs (see the end of post for demo)!
Here are a few projects that we’ve done with the I/O Shield, but we’d love to see other project ideas!
Having the 8 LEDs Run back and forth in sequence (using an Array):
/*Arrays Demonstrates the use of an array to hold pin numbers in order to iterate over the pins in a sequence. Lights multiple LEDs in sequence, then in reverse. Unlike the For Loop tutorial, where the pins have to be contiguous, here the pins can be in any random order. The circuit: * on an Arduino and chipKIT uno32 LEDs from pins 2 through 7 to ground * on the chipKIT I/O Expander Shield it's pins 26-33 created 2006 by David A. Mellis modified 5 Jul 2009 by Tom Igoe modified by Larissa Swanland Digilent Inc-2014
This example code is in the public domain. http://www.arduino.cc/en/Tutorial/Array */ int timer = 100; // The higher the number, the slower the timing. int ledPins[] = { 33, 32, 31, 30, 29, 28, 27, 26 }; // an array of pin numbers to which LEDs are attached int pinCount = 8; // the number of pins (i.e. the length of the array) void setup() { int thisPin; // the array elements are numbered from 0 to (pinCount - 1). // use a for loop to initialize each pin as an output: for (int thisPin = 0; thisPin < pinCount; thisPin++) { pinMode(ledPins[thisPin], OUTPUT); } } void loop() { // loop from the lowest pin to the highest: for (int thisPin = 0; thisPin < pinCount; thisPin++) { // turn the pin on: digitalWrite(ledPins[thisPin], HIGH); delay(timer); // turn the pin off: digitalWrite(ledPins[thisPin], LOW); } // loop from the highest pin to the lowest: for (int thisPin = pinCount - 1; thisPin >= 0; thisPin--) { // turn the pin on: digitalWrite(ledPins[thisPin], HIGH); delay(timer); // turn the pin off: digitalWrite(ledPins[thisPin], LOW); } }
Using the Analog Potentiometer to Change the Number of LEDs:
/*Digilent Inc. Larissa Swanland 2014 Code written to use with chipKIT Uno32/UC32 + the IO Expander Shield focus with 10K Potiometer and 8 LED's to see the pin-outs please look at page 8 in IO Expander reference guide: https://digilentinc.com/Data/Products/CHIPKIT-BASIC-IO-SHIELD/chipKIT%20Basic%20IO%20Shield_rm.pdf*/ const int potPin= A0; //Pin that the 10K Pot is attached to //LED Outputs using an Array, please see Array Code for example int i; int led[] = {33, 32, 31, 30, 29, 28, 27, 26 }; // an array of pin numbers to which LEDs are attached //variables that will change: int potRead= 0; int potVal= 0; //Mapped Value of Pot int lastPot=0; //last value of Pot Stored void setup(){ pinMode(potPin, INPUT); // declare Pot as input //intialize the LED pins for (int i=0; i < 9; i++){ pinMode(led[i], OUTPUT); } Serial.begin(9600); } void loop(){ potRead=analogRead(potPin); //read Analog Value attached to Pot potVal= map(potRead, 0, 1023, 0, 8); //map the value from 0-1023 to 0-7 (coincides with LED Array) //compare old reading to new reading if (potVal!= lastPot) { //if current value is different from old lastPot = potVal; //then store the new value Serial.print(potVal); //for debugging using Serial monitor for (int i=0; i<potVal+1; i++){ digitalWrite(led[i],HIGH); } } else { for(int i= potVal-1; i>=0; i--){ digitalWrite(led[i], LOW); } } }
RGB Analog Strip:

/*Digilent Inc. Larissa Swanland 2014- Fade colors for RGB Strips Connect Analog RGB to individual FET channels and power to shared 12V Power Supply (see photo)*/
#define REDPIN 5 #define GREENPIN 3 #define BLUEPIN 9 #define FADESPEED 5 // make this higher to slow down void setup() { pinMode(REDPIN, OUTPUT); pinMode(GREENPIN, OUTPUT); pinMode(BLUEPIN, OUTPUT); } void loop() { int r, g, b; // fade from blue to violet for (r = 0; r < 256; r++) { analogWrite(REDPIN, r); delay(FADESPEED); } // fade from violet to red for (b = 255; b > 0; b--) { analogWrite(BLUEPIN, b); delay(FADESPEED); } // fade from red to yellow for (g = 0; g < 256; g++) { analogWrite(GREENPIN, g); delay(FADESPEED); } // fade from yellow to green for (r = 255; r > 0; r--) { analogWrite(REDPIN, r); delay(FADESPEED); } // fade from green to teal for (b = 0; b < 256; b++) { analogWrite(BLUEPIN, b); delay(FADESPEED); } // fade from teal to blue for (g = 255; g > 0; g--) { analogWrite(GREENPIN, g); delay(FADESPEED); } }
Combining Switches + Potentiometer + Analog RGB Strips:
/*Digilent Inc Larissa Swanland 2014 S4- is the on-off switch S1-3 are the switches that control the channel on the RGB LEDs The Analog Pot will control brightness*/ const int potPin= A0; //Pin that the 10K Pot is attached to const int red = 5; // Pin 3 when LED Strip is connected const int blue= 3; // Pin 5 when LED Strip is connected const int green= 9; // Pin 6 When LED Strip is connected const int sw1= 35; const int sw2= 8; const int sw3= 7; const int sw4= 2; int s1,s2,s3,s4; int potRead= 0; int potVal=0; //Mapped Value of Pot-- intensity int lastPot=0; //last value of Pot Stored void setup(){ pinMode(sw1, INPUT); pinMode(sw2, INPUT); pinMode(sw3, INPUT); pinMode(sw4, INPUT); pinMode(potPin, INPUT); // declare Pot as input pinMode(red, OUTPUT); pinMode(blue, OUTPUT); pinMode(green, OUTPUT); Serial.begin(9600); } void loop(){ //read the switch values s1= digitalRead(sw1); //red s2= digitalRead(sw2); //green s3= digitalRead(sw3); //blue s4= digitalRead(sw4); //on or off potRead=analogRead(potPin); //read Analog Value attached to Pot potVal=map(potRead, 0, 1023, 0, 256); //map the pot to the value of RGB Brightness if(potVal!=lastPot){ lastPot= potVal; Serial.print(potVal);} if(s4==0)// the last switch is on { analogWrite(red, 0); analogWrite(green,0); analogWrite(blue, 0); }else{ analogWrite(red, s1*potVal); analogWrite(green,s2*potVal); analogWrite(blue,s3*potVal); } } Combine all of the sketches together!
/*Digilent Inc Larissa Swanland 2014 S4- will make the LEDs cycle through a routine (there is a slight delay) S1-3 are the switches that control the channel on the RGB LEDs The Analog Pot will speed of the cycle*/ const int potPin= A0; //Pin that the 10K Pot is attached to const int red = 5; // Pin 3 when LED Strip is connected const int blue= 3; // Pin 5 when LED Strip is connected const int green= 9; // Pin 6 When LED Strip is connected const int sw1= 35; const int sw2= 8; const int sw3= 7; const int sw4= 2; int s1,s2,s3,s4; int potRead= 0; int potVal=0; //Mapped Value of Pot-- intensity int lastPot=0; //last value of Pot Stored int fadespeed=1; //fadespeed void setup(){ pinMode(sw1, INPUT); pinMode(sw2, INPUT); pinMode(sw3, INPUT); pinMode(sw4, INPUT); pinMode(potPin, INPUT); // declare Pot as input pinMode(red, OUTPUT); pinMode(blue, OUTPUT); pinMode(green, OUTPUT); Serial.begin(9600); } void loop(){ //read the switch values s1= digitalRead(sw1); //red s2= digitalRead(sw2); //green s3= digitalRead(sw3); //blue s4= digitalRead(sw4); //on or off potRead=analogRead(potPin); //read Analog Value attached to Pot potVal=map(potRead, 0, 1023, 0, 256); //map the pot to the value of RGB Brightness while(potVal!=lastPot){ lastPot= potVal; Serial.print(potVal); } if (s4==1)// the last switch is on { fade(); }else{ analogWrite(red, s1*potVal); analogWrite(green,s2*potVal); analogWrite(blue,s3*potVal); } } void fade(){ int r, g, b; fadespeed= 255/potVal; // fade from blue to violet for (r = 0; r < 256; r++) { analogWrite(red, r); delay(fadespeed); } // fade from violet to red for (b = 255; b > 0; b--) { analogWrite(blue, b); delay(fadespeed); } // fade from red to yellow for (g = 0; g < 256; g++) { analogWrite(green, g); delay(fadespeed); } // fade from yellow to green for (r = 255; r > 0; r--) { analogWrite(red, r); delay(fadespeed); } // fade from green to teal for (b = 0; b < 256; b++) { analogWrite(blue, b); delay(fadespeed); } // fade from teal to blue for (g = 255; g > 0; g--) { analogWrite(green, g); delay(fadespeed); } }
This is very cool!!
I just got this kit and I just tried the First two programs here on this pages to verify the that the board works and it does!!
Thank you for posting this!!
However I can not get the OLED Demo to work to verify that the display works.
Can you post a program that I can copy and paste like the other one for the OLED?
I did everything I was supposed to do I believe that is correct as described from the CHIPKIT website and your video (using Windows instead) tutorial using the demo file from Diligent and it fails to work.
I get a compilation error, so it never gets to the point to upload the program to the uc32.
Many of the other demos work as well so I know the uc32 is working properly.
I just got this so I need to verify that if the OLED is working or not, in the case if that I need to send it back to the supplier.
Thanks!! Jer 😀
Hi geraldfryjr,
I have a guess at what the problem might be, but what compilation error are you receiving? Is it saying something about not being able to find “IOShieldOled.h”?
Thanks,
James COlvin
Yes, Thank you for the reply.
I did finally get it to work after I had figured out what directory to put the Library files in.
There was also an issue with the version of MPIDE that I was using as well switching to an earlier version I got it to work and then later I switched to the latest Beta version and it worked as well.
But, What was supposed to be the current version at the time of my post did not work correctly.
Sorry for the late response as I had mean’t to post this info and version numbers I am using.
Once I got it to compile correctly everything worked on the Basic I/O board and Uc32!!
I can’t even explain how ecstatic I was and still am at this cool little system.
I had even found another demo for the OLED the other day and it worked without a hitch.
Now I am trying to get the Linux version of MPIDE to work but I haven’t had much luck with it.
I haven’t messed with it in a month or so, so I forget all of the details right now.
I will try to get back here shortly with all of the details I have found so that it will quickly help others at getting theirs to work to if anyone has any issues.
Thanks !!!!
jer 🙂
I found my data for using a PC.
When you install MPIDE it creates a folder called MPIDE and in this folder is where your Sketch’s or projects go and are saved.
But this is not were you put the libraries for the Basic I/O shield like it says in the video.
Maybe for a MAC but not a PC.
The Libaries for the Basic I/O go in a folder where all of the original MPIDE files are kept as follows,
MPIDE/Hardware/Pic32/libraries/ “the 3 needed Basic I/O resources go here”
Then the Compiler will find them and compile without errors.
I don’t remember whether or not I got it to work in linux since I had wiped that version of my distro out and started all over due to an error that was caused when I installed MPLABX Version 2.26.
Since then I am using ver 2.30 and it works okay I think.
I have had some issues with some programs I have written in assembly in ver. 2.15 and failed in ver. 2.26 and seems to be working in ver. 2.30 as well.
But I am still having issues with my C programs in MPLABX 2.30 in Linux but that is another issue and I haven’t had the time lately to iron that out yet.
It is just another can’t find the libraries issues there too.
Meanwhile it works fine in windows.
I use XP64, Win7 and Ultimate Edition 4.3 Linux (KDE) for my choice of OS’s
Cheers!!
jer 🙂
Hi jer, I apologize for the delay.
I’m not familiar with MPLABX and how all that will go, but I am more familiar with MPIDE. You can put the Basic I/O Shield libraries in the created “mpide” folder. You would need to create a folder within the mpide folder called “Libraries” and place them in there (as mentioned in the video). Then, what you would need to do is open up MPIDE itself and go to File->Preferences. You then need to change the Sketchbook location to where you are storing all of your sketches. In my case thats Users\jcolvin\Documents\mpide for both a windows 7 and windows 10. Then it will be able to find all of the library files (once you have restarted MPIDE).
Let me know if you have any more questions!
Thanks,
James Colvin