Hello,

I'm trying to display the program Hello world https://github.com/adafruit/Adafruit-RGB-LCD-Shield-Library/blob/master/examples/HelloWorld/HelloWorld.ino with the Adafruit-RGB-LCD-Shield https://www.adafruit.com/product/714 with the SDA (20) and the SCL (21) but is not working.

The shield is correctly powered. I think that the issue is in the following code:
https://github.com/adafruit/Adafruit-RGB-LCD-Shield-Library/blob/master/Adafruit_RGBLCDShield.cpp

`
#include "Adafruit_RGBLCDShield.h"

#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <Wire.h>
#ifdef SAM3X8E // Arduino Due
#define WIRE Wire1
#else
#define WIRE Wire
#endif

#if ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif
`
When the code define Wire Wire1 for the arduino Due, therefore the pins SDA (20) and SCL (21) cannot be used. Only the pins SCL1 and SDA1.
While I would like to use the pins SCL1 and SDA1 and SDA (20) and SCL (21).

Can you change the line #define WIRE Wire1 to use the four pins ?

Thanks for the help .

Ada-peeps,
What's the chances of getting this ported to Particle (formerly spark)? I gave it a shot, but kind of failed :(

Thanks,
James

Hi,
recently bought the RGB LCD Shield Kit (http://www.adafruit.com/products/714).

It seems that Buttons are not completely debounced. The tutorial (http://learn.adafruit.com/rgb-lcd-shield/using-the-rgb-lcd-shield) states otherwise: "Note that the library handles button debouncing internally. There is no need to debounce the buttons in your code.".

See this gist with a sample program, to see how a value jumps due to bouncing buttons:
https://gist.github.com/osune/8026836

Thanks.

Hello,

I bought https://www.adafruit.com/product/1115
LCD Shield Kit w/ 16x2 Character Display - Only 2 pins used! - BLUE AND WHITE

It's not very clear if code example in this project can be use to test this LCD/keypad shield.

I tried to compile and run example.

At startup, backlight is on but nothing appears on screen.

Any idea?

No clue, but I'll be taking a look at it.

Putting this here so I don't forget

• Arduino board: Uno Wifi Rev 2

• Arduino IDE version (found in Arduino -> About Arduino menu): 1.8.13

• List the steps to reproduce the problem below (if possible attach a sketch or
  copy the sketch code in too):
  Open Example sketch "Hello World", select board: uno Wifi Rev 2, Verify Sketch

In trying to simply compile the Adafruit RGB LCD Shield "Hello World" example, I am getting this error:

Arduino: 1.8.12 (Windows Store 1.8.33.0) (Windows 10), Board: "Arduino Uno WiFi Rev2, ATMEGA328"

In file included from C:\Users\...\Arduino\libraries\Adafruit_RGB_LCD_Shield_Library\Adafruit_RGBLCDShield.cpp:17:0:

C:\Users\...\Arduino\libraries\Adafruit_RGB_LCD_Shield_Library\Adafruit_RGBLCDShield.h:68:44: error: expected class-name before '{' token

 class Adafruit_RGBLCDShield : public Print {

                                            ^

exit status 1
Error compiling for board Arduino Uno WiFi Rev2.

I think I found some clue to the problem:

Because the uno wifi R2 is a megaavr board and not an avr board, I went looking for the source code for Print.h. These apparently are not in the same location. From what I could find, there are at least two versions. I could not find the avr file (C:\Users...\ArduinoData\packages\arduino\hardware\avr folder is blank)

However, the megaavr folder was not. I did find Print.h in:
(C:\Users...\ArduinoData\packages\arduino\hardware\megaavr\1.8.6\cores\arduino\api)

While there, I noticed it defined the "Print" class within the "arduino" namespace.

namespace arduino {

class Print
{

I thought maybe there's another Print.h in a different namespace that is conflicting.

So, I edited the RGB LCD Shield header file to say:
class Adafruit_RGBLCDShield : public arduino::Print {
and it compiles for the Uno Wifi Rev 2. However, the arduino namespace appears to not be known to the avr boards, and now won't compile for them, even if I use
using namespace arduino
in the RGB_LCD header file.

I also checked and this behavior also happens with the liquid crystal library, upon which this is based, so maybe it's their issue to resolve?

./examples/HelloWorld.pde
Variable declared before the main loop that doesn't appear to be used.
...
uint8_t i=0;
...

No comments on this line either.

My code is as follows:
`// Connect pin #12 of the expander to Analog 5 (i2c clock)
// Connect pin #13 of the expander to Analog 4 (i2c data)
// Connect pins #15, 16 and 17 of the expander to 3V3 (address selection)
// Connect pin #9 of the expander to 5V (power)
// Connect pin #10 of the expander to ground (common ground)
// Connect pin #18 through a ~10kohm resistor to 5V (reset pin, active low)

// Input #0 is on pin 21 so connect a button or switch from there to ground

// include the library code:
#include <Wire.h>
#include <Adafruit_RGBLCDShield.h>
#include <utility/Adafruit_MCP23017.h>
//#include "Adafruit_MCP23017.h"

// The shield uses the I2C SCL and SDA pins. On classic Arduinos
// this is Analog 4 and 5 so you can't use those for analogRead() anymore
// However, you can connect other I2C sensors to the I2C bus and share
// the I2C bus.
Adafruit_RGBLCDShield lcd = Adafruit_RGBLCDShield();
Adafruit_MCP23017 mcp;

// These #defines make it easy to set the backlight color
#define RED 0x1
#define YELLOW 0x3
#define GREEN 0x2
#define TEAL 0x6
#define BLUE 0x4
#define VIOLET 0x5
#define WHITE 0x7
#define addr1 7 // 7 = A1 high, A2 high, A3 high

void setup() {
// Debugging output
Serial.begin(9600);
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
mcp.begin(addr1);
mcp.pinMode(0, INPUT);
mcp.pullUp(0, HIGH); // turn on a 100K pullup internally

pinMode(13, OUTPUT); // use the p13 LED as debugging

// Print a message to the LCD. We track how long it takes since
// this library has been optimized a bit and we're proud of it :)
int time = millis();
lcd.print("Hello, world!");
time = millis() - time;
Serial.print("Took "); Serial.print(time); Serial.println(" ms");
lcd.setBacklight(RED);
}

uint8_t i=0;
void loop() {
// set the cursor to column 0, line 1
// (note: line 1 is the second row, since counting begins with 0):
lcd.setCursor(0, 1);
// print the number of seconds since reset:
lcd.print(millis()/1000);

uint8_t buttons = lcd.readButtons();

if (buttons) {
lcd.clear();
lcd.setCursor(0,0);
if (buttons & BUTTON_UP) {
lcd.print("UP ");
}
if (buttons & BUTTON_DOWN) {
lcd.print("DOWN ");
}
if (buttons & BUTTON_LEFT) {
lcd.print("LEFT ");
}
if (buttons & BUTTON_RIGHT) {
lcd.print("RIGHT ");
}
if (buttons & BUTTON_SELECT) {
lcd.print("SELECT ");
}
}
digitalWrite(13, mcp.digitalRead(0));
}`

for some reson the hat is working but the other MCP23017 chip

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please fill in the following fields to provide enough troubleshooting information.
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Is there a reason why the MCP23017 library in the Adafruit-RGB-LCD-Shield-Library project and in the Adafruit-MCP23017-Arduino-Library project are different, or should they be synced?
Thanks for the help.

I think it has some important information
Thanks

There's no function/method that allows settings the i2c address hardwired on the back of the module. How does one provide the address?