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nseidlenseidle
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Merge pull request #10 from fourstix/set_rgb_backlight
Add Set rgb backlight command to set RGB Backlight in one command without flicker
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‎firmware/Examples/Advanced/OpenLCD_Qwiic_RGB_Backlight/OpenLCD_Qwiic_RGB_Backlight.ino

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/*
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* This sketch changes the backlight color and displays text using
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* the OpenLCD functions.
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*
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*The circuit:
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* Sparkfun RGB OpenLCD Serial display connected through
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* a Sparkfun Qwiic adpater to an Ardruino with a
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* Qwiic shield or a Sparkfun Blackboard with Qwiic built in.
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*
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* The Qwiic adapter should be attached to the display as follows:
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*
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* Display Qwiic Qwiic Cable Color
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* GND GND Black
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* RAW 3.3V Red
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* SDA SDA Blue
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* SCL SCL Yellow
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*
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* Note: If you connect directly to a 5V Arduino instead, you *MUST* use
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* a level-shifter to convert the i2c voltage levels down to 3.3V for the display.
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OpenLCD is an LCD with Serial/I2C/SPI interfaces.
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By: Nathan Seidle
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SparkFun Electronics
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Date: April 19th, 2015
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License: This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license).
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OpenLCD gives the user multiple interfaces (serial, I2C, and SPI) to control an LCD. SerLCD was the original
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serial LCD from SparkFun that ran on the PIC 16F88 with only a serial interface and limited feature set.
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This is an updated serial LCD.
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This example shows how to change brightness of the three backlight controls.
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Please Note: 0x72 is the 7-bit I2C address. If you are using a different language than Arduino you will probably
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need to add the Read/Write bit to the end of the address. This means the default read address for the OpenLCD
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is 0b.1110.0101 or 0xE5 and the write address is 0b.1110.0100 or 0xE4.
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For more information see https://learn.sparkfun.com/tutorials/i2c
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Note: This code expects the display to be listening at the default I2C address. If your display is not at 0x72, you can
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do a hardware reset. Tie the RX pin to ground and power up OpenLCD. You should see the splash screen
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then "System reset Power cycle me" and the backlight will begin to blink. Now power down OpenLCD and remove
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the RX/GND jumper. OpenLCD is now reset.
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To get this code to work, attached an OpenLCD to an Arduino Uno using the following pins:
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SCL (OpenLCD) to A5 (Arduino)
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SDA to A4
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VIN to 5V
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GND to GND
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The OpenLCD has 4.7k pull up resistors on SDA and SCL. If you have other devices on the
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I2C bus then you may want to disable the pull up resistors by clearing the PU (pull up) jumper.
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OpenLCD will work at 400kHz Fast I2C. Use the .setClock() call shown below to set the data rate
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faster if needed.
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Command cheat sheet:
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ASCII / DEC / HEX
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'|' / 124 / 0x7C - Put into setting mode
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Ctrl+c / 3 / 0x03 - Change width to 20
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Ctrl+d / 4 / 0x04 - Change width to 16
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Ctrl+e / 5 / 0x05 - Change lines to 4
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Ctrl+f / 6 / 0x06 - Change lines to 2
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Ctrl+g / 7 / 0x07 - Change lines to 1
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Ctrl+h / 8 / 0x08 - Software reset of the system
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Ctrl+i / 9 / 0x09 - Enable/disable splash screen
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Ctrl+j / 10 / 0x0A - Save currently displayed text as splash
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Ctrl+k / 11 / 0x0B - Change baud to 2400bps
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Ctrl+l / 12 / 0x0C - Change baud to 4800bps
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Ctrl+m / 13 / 0x0D - Change baud to 9600bps
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Ctrl+n / 14 / 0x0E - Change baud to 14400bps
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Ctrl+o / 15 / 0x0F - Change baud to 19200bps
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Ctrl+p / 16 / 0x10 - Change baud to 38400bps
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Ctrl+q / 17 / 0x11 - Change baud to 57600bps
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Ctrl+r / 18 / 0x12 - Change baud to 115200bps
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Ctrl+s / 19 / 0x13 - Change baud to 230400bps
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Ctrl+t / 20 / 0x14 - Change baud to 460800bps
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Ctrl+u / 21 / 0x15 - Change baud to 921600bps
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Ctrl+v / 22 / 0x16 - Change baud to 1000000bps
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Ctrl+w / 23 / 0x17 - Change baud to 1200bps
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Ctrl+x / 24 / 0x18 - Change the contrast. Follow Ctrl+x with number 0 to 255. 120 is default.
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Ctrl+y / 25 / 0x19 - Change the TWI address. Follow Ctrl+x with number 0 to 255. 114 (0x72) is default.
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Ctrl+z / 26 / 0x1A - Enable/disable ignore RX pin on startup (ignore emergency reset)
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'-' / 45 / 0x2D - Clear display. Move cursor to home position.
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/ 128-157 / 0x80-0x9D - Set the primary backlight brightness. 128 = Off, 157 = 100%.
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/ 158-187 / 0x9E-0xBB - Set the green backlight brightness. 158 = Off, 187 = 100%.
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/ 188-217 / 0xBC-0xD9 - Set the blue backlight brightness. 188 = Off, 217 = 100%.
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For example, to change the baud rate to 115200 send 124 followed by 18.
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'+' / 43 / 0x2B - Set Backlight to RGB value, follow + by 3 numbers 0 to 255, for the r, g and b values to set.
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For example, to change the backlight to yellow send + followe by 255, 255 and 0.
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*/
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#include <Wire.h>
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#define DISPLAY_ADDRESS1 0x72 //This is the default address of the OpenLCD
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void setup()
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{
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Wire.begin(); //Join the bus as master
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//By default .begin() will set I2C SCL to Standard Speed mode of 100kHz
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Wire.setClock(400000); //Optional - set I2C SCL to High Speed Mode of 400kHz
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Serial.begin(9600); //Start serial communication at 9600 for debug statements
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Serial.println("OpenLCD Example Code");
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//Send the reset command to the display - this forces the cursor to return to the beginning of the display
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Wire.beginTransmission(DISPLAY_ADDRESS1);
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.endTransmission();
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Wire.print("Testing Set RGB");
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delay(2000);
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}
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void loop()
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{
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//Turn off backlight (black)
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Serial.println("Setting RGB backlight to black");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0x00); //Send the red value
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Wire.write(0x00); //Send the green value
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Wire.write(0x00); //Send the blue value
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Wire.print("Black (Off)!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set red backlight
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Serial.println("Setting RGB backlight to red");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0xFF); //Send the red value
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Wire.write(0x00); //Send the green value
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Wire.write(0x00); //Send the blue value
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Wire.print("Red!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set Orange backlight
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Serial.println("Setting RGB backlight to orange");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0xFF); //Send the red value
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Wire.write(0x8C); //Send the green value
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Wire.write(0x00); //Send the blue value
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Wire.print("Orange!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set yellow backlight
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Serial.println("Setting RGB backlight to yellow");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0xFF); //Send the red value
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Wire.write(0xFF); //Send the green value
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Wire.write(0x00); //Send the blue value
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Wire.print("Yellow!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set green backlight
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Serial.println("Setting RGB backlight to green");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0x00); //Send the red value
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Wire.write(0xFF); //Send the green value
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Wire.write(0x00); //Send the blue value
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Wire.print("Green!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set blue backlight
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Serial.println("Setting RGB backlight to blue");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0x00); //Send the red value
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Wire.write(0x00); //Send the green value
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Wire.write(0xFF); //Send the blue value
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Wire.print("Blue!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set violet backlight
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Serial.println("Setting RGB backlight to violet");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0xA0); //Send the red value
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Wire.write(0x20); //Send the green value
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Wire.write(0xF0); //Send the blue value
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Wire.print("Violet!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Turn on all (white)
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Serial.println("Setting RGB backlight to white");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0xFF); //Send the red value
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Wire.write(0xFF); //Send the green value
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Wire.write(0xFF); //Send the blue value
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Wire.print("White!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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//Set to Gray
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Serial.println("Setting RGB backlight to gray");
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Wire.beginTransmission(DISPLAY_ADDRESS1); // transmit to device #1
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('-'); //Send clear display command
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Wire.write('|'); //Put LCD into setting mode
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Wire.write('+'); //Send the Set RGB command
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Wire.write(0x80); //Send the red value
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Wire.write(0x80); //Send the green value
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Wire.write(0x80); //Send the blue value
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Wire.print("Gray!");
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Wire.endTransmission(); //Stop I2C transmission
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delay(2000);
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}

‎firmware/OpenLCD/OpenLCD.ino

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@@ -71,11 +71,17 @@ byte customCharData[8]; //Records incoming custom character data
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byte customCharSpot = 0 ; //Keeps track of where we are in custCharData array
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byte customCharNumber = 0; //LCDs can store 8 custom chars, this keeps track
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//New variables for Set RGB command
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byte rgbData[3]; //Records incoming backlight rgb triplet
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byte rgbSpot = 0 ; //Keeps track of where we are in rgbData array
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bool modeCommand = false; //Used to indicate if a command byte has been received
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bool modeSetting = false; //Used to indicate if a setting byte has been received
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bool modeContrast = false; //First setting mode, then contrast change mode, then the value to change to
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bool modeTWI = false; //First setting mode, then TWI change mode, then the value to change to
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bool modeRecordCustomChar = false; //First setting mode, then custom char mode, then record 8 bytes
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//New command mode for Set RGB
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bool modeSetRGB = false; //First setting mode, then RGB mode, then get 3 bytes
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// Struct for circular data buffer
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// Data received over UART, SPI and I2C are all sent into a single buffer
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buffer.tail = (buffer.tail + 1) % BUFFER_SIZE; // and update the tail to the next oldest
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//If the last byte received wasn't special
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if (modeCommand == false && modeSetting == false && modeContrast == false && modeTWI == false && modeRecordCustomChar == false)
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{
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if (modeCommand == false && modeSetting == false && modeContrast == false && modeTWI == false
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&& modeRecordCustomChar == false && modeSetRGB == false) {
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//Check to see if the incoming byte is special
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if (incoming == SPECIAL_SETTING) modeSetting = true; //SPECIAL_SETTING is 127
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else if (incoming == SPECIAL_COMMAND) modeCommand = true; //SPECIAL_COMMAND is 254
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currentFrame[characterCount++] = incoming; //Record this character to the display buffer
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if (characterCount == settingLCDwidth * settingLCDlines) characterCount = 0; //Wrap condition
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}
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//Set Backlight RGB in one command to eliminate flicker
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else if (incoming == 43) {
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modeSetRGB = true;
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}
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modeSetting = false;
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}
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else if (modeTWI == true)
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changeContrast(incoming);
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modeContrast = false; //Exit this mode
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}
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else if (modeSetRGB == true)
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{
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//We get into this mode if the user has sent the + (43) command to set the backlight rgb values
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rgbData[rgbSpot] = incoming; //Record this byte to the array
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rgbSpot++;
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if (rgbSpot > 2)
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{
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//Once we have 3 bytes, stop listening and change the backlight color
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rgbSpot = 0;
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changeBacklightRGB(rgbData[0], rgbData[1], rgbData[2]);
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modeSetRGB = false; //Exit this mode
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} //if (rgbSpot > 2)
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} // else if modeSetRGB
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}
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‎firmware/OpenLCD/Setting_Control.ino

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displayFrameBuffer(); //Display what was there before
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}
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//Changes the brightness of all three backlight pins and updates the EEPROM locations
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//with their rgb values to eliminate flicker. Incoming brightness values should be 0 to 255
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void changeBacklightRGB(byte red, byte green, byte blue) {
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//update red
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EEPROM.write(LOCATION_RED_BRIGHTNESS, red); //Record new setting
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analogWrite(BL_RW, 255 - red); //Controlled by PNP so reverse the brightness value
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//update green
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EEPROM.write(LOCATION_GREEN_BRIGHTNESS, green); //Record new setting
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analogWrite(BL_G, 255 - green); //Controlled by PNP so reverse the brightness value
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//update blue (SoftPWM)
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EEPROM.write(LOCATION_BLUE_BRIGHTNESS, blue); //Record new setting
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//analogWrite(BL_B, 255 - brightness); //Controlled by PNP so reverse the brightness value
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SoftPWMSet(BL_B, 255 - blue); //Controlled by software PWM
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petSafeDelay(SYSTEM_MESSAGE_DELAY);
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displayFrameBuffer(); //Display what was there before
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}
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//Changes the baud rate setting
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//Assumes caller is passing a number 0 to 12
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void changeUARTSpeed(byte setting)

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