Component: LCD I2C (Backpack) ()

Author	Matrix Ltd
Version	2.2
Category

LCD I2C (Backpack) component

Standard alphanumeric LCD based on a standard I2C control bus. Usually using either a PIC device or Microchip IO expander IC.

Component Pack

DISPLAYS

Detailed description

No detailed description exists yet for this component

Examples

A simple example that shows how to use some common functions.

Backpack LCD Example

If the display is not showing the expected characters, the I2c address or contrast could be wrong.

It's best to keep the jumper connected since the backlight is enabled by default.

The correct I2C address can be determined by using an IC2 Address Sniffer

The I2C address to use is the one within the first set of square brackets.

For example, with my backpack display, the correct address to use is 0x3F [63]:

The other two Addresses i.e. 0x56 [86] and 0x68 [104] is for my 24C32 EEPROM and DS3231 RTC respectively.

Note The I2c addresses scan will repeat every 5seconds.

The sniffer will send data to your PC via UART to USB.

The Arduino range and clones will have it built-in.

More details on I2C can be found here,

Matrix Flowcode Blog: Simplified communications I2C and SPI

Downloadable macro reference

	Clear
- VOID	Return

	PrintString
- STRING	Text
- VOID	Return

	PrintAscii
Takes the ascii value for a character and prints the character
- BYTE	character
- VOID	Return

	PrintNumber
Allows you to print a number. This is limited to a signed-INT, -32768 to 32767
- INT	Number
- VOID	Return

	RAMWrite
Modifies the internal memory of the LCD to allow for up to 8 customised characters to be created and stored in the device memory
- BYTE	Index
- BYTE	d0
- BYTE	d1
- BYTE	d2
- BYTE	d3
- BYTE	d4
- BYTE	d5
- BYTE	d6
- BYTE	d7
- VOID	Return

	BacklightControl
- BYTE	State
- VOID	Return

	ClearLine
- BYTE	Line
- VOID	Return

	Cursor
Moves the cursor on the LCD Display
- BYTE	x
- BYTE	y
- VOID	Return

	Command
Use this method/macro to send a specific command to the LCD. Refer to the Matrix Multimedia EB006 datasheet for a list of supported instructions. For Non-Matrix LCD's refer to the manufacturers datasheet.
- BYTE	instruction
- VOID	Return

	PrintFormattedNumber
Will allow you to print a number up to 32-bits with signed or unsigned formatting. Signed = -2147483648 to 2147483647 Unsigned = 0 to 4294967295
- ULONG	Number
Enter the number or variable to print to the LCD
- BOOL	Format
0=Signed, 1=Unsigned
- VOID	Return

	ScrollDisplay
Scrolls the display left or right by a number of given positions.
- BYTE	position
- BYTE	direction
- VOID	Return

	PrintFloat
Print a Float number rounded up to a specified amount of decimal places.
- FLOAT	Number
Enter the number or variable to print to the LCD
- BYTE	DecimalPlaces
Enter how many decimal places to round up to (1 - 6)
- VOID	Return

	Start
Startup routine required by the hardware device.
- VOID	Return

	SetI2CAddress
Allows the I2C device address to be dynamically changed in software without having to re-compile. Can be called before the first Start macro or at any point after.
- BYTE	Address
New I2C Device Address excluding R/W bit - Range 0 - 127
- VOID	Return

Property reference

	Properties
	I2C Config
	LCD Address
	Channel
Channel selection
	Baud Select
Baud rate option selector
	Baud Rate
Baud rate to be used
	Stop Delay
On older microcontroller devices there is a potential for the I2C hardware channel to lock up if there is not a 10ms delay between an I2C stop event and the next I2C start event. Most modern microcontrollers will not have a problem so this property can be disabled to speed up the I2C communications.
	Connections
	SDA
Pin used for SDA (data signal)
	SCL
Pin used for SCL (clock signal)
	LCD Configuration
	Rows
	Columns
	Use Backlight
Controls if the backlight is controlled as part of the main data routine or if it is handled separately.
	Simulation
	Simulate Comms
Allows the communications to be simulated via an injector component.