Matrix user forums

I am running v8.2.2.15.
I have tried to get a generic 1602 display working using the I2C protocol.
I have generated a simple code on flow code 8 and on simulation this works.
When uploading to the Arduino, nothing happens.
I have run a the same hardware in the IDE environment and this is working.
I have toggled the backlight on and off- no luck
I am using a generic 1602 display with a PCF8574 I2C piggy backed
data sheet file:///I:/Central%20Beds%20Engineering/RQF%20Unit%206%20Microcontroller%20Systems%20for%20Engineers/data%20sheets/PCF8574_PCF8574A%20I2C%20chip%20set.pdf
Unable to attach the arduino code so here is the code

//web page below gives pin outs
//https://www.makerguides.com/character-i ... -tutorial/
#include <Wire.h>
#include <LCD.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); // Addr, En, Rw, Rs, d4, d5, d6, d7, backlighpin, polarity

void setup()
{
lcd.begin(16,2);
lcd.backlight();
lcd.setCursor(0, 0);
lcd.print("Hello world!");
lcd.setCursor(0, 1);
lcd.print("Row number: ");
lcd.setCursor(12, 1);
lcd.print("2");
}
void loop()
{

}

Just to recap,
using IDE load the programme and the I2C LCD works
USing Flowcode programme- the software emulator is working
Upload code to hardware- does not work!

This is the first time on the forum, I hope I have included everything

regards

ChrisP

Hi Chris,
Welcome to the forums.
I also have the PCF8574 I2C piggy backed with 20x4 LCD
It works well with PIC or Arduino.
Attached is a demo flowchart that works on the Arduino uno.
Just change the LCD for your type I.e 2 x 16
The component to use within Flowcode is LCD I2C (Backpack).

Hello Martin,
Thanks for answering.
I have tried your programme and it did not work?
The back light is on, but not displaying anything.
When uploading the programme I ensured the TX and RX lights were in their normal uploading sequence.
I have also belled the SDA to pin C4 and the SCL to pin C5 (GND and Vcc would be good as light is on)

Previously with Liams help I did use pull up 10K resistors on both SDA and SCL lines.
I have used the arduino, arduino Uno and the Elegoo arduino Uno boards.
I did change the target to the Uno R3 (sorry forgot to tell you earlier) to match my boards

Same problem simulation ok but cannot load onto hardware?

What happens when you rotate the trimmer on the back while light is on?

Hello Martin,
When altering the trimmer pot, it is doing as expected, fully clockwise all the top row 16 squares (made up of 5x8 smaller squares) is brighter and the bottom can be see but darker that the non character bits
fully anti clockwise character square disappear.
Just the same as the 10K pot when connecting the D4 to D7 configuration.

regards

Chris

Can you try the attached I2C address sniffer.
The top value within brackets, is the value you should have in the LCD properties.
Yours maybe different to mine?