Introduction:
Connection mode 12 supports up to four I2C LCD adapters, each addressed independently.
The system variable LCD_I2C_Address_Current specifies which adapter’s address subsequent LCD write actions target. To use multiple adapters, define an address for each
one, then set LCD_I2C_Address_Current to the address of the adapter you want to write to next.
Command Availability:
Available on all microcontrollers, using LCD_IO connection mode 12.
Example:
' ----- Define Hardware settings
' Define I2C settings - CHANGE PORTS
#define I2C_MODE Master
#define I2C_DATA PORTC.4
#define I2C_CLOCK PORTC.5
#define I2C_DISABLE_INTERRUPTS ON
'Set up LCD
#define LCD_IO 12
#define LCD_WIDTH 20 ;specified lcd width for clarity only. 20 is the default width
#define LCD_I2C_Address_1 0x4E ; LCD 1
#define LCD_I2C_Address_2 0x4C ; LCD 2
#define LCD_I2C_Address_3 0x4A ; LCD 3
#define LCD_I2C_Address_4 0x49 ; LCD 4
;Change to the correct LCD by setting
;LCD_I2C_Address_Current to the correct address then write to LCD.
LCD_I2C_Address_Current = LCD_I2C_Address_1
Print "Adapter #1"
LCD_I2C_Address_Current = LCD_I2C_Address_2
Print "Adapter #2"
LCD_I2C_Address_Current = LCD_I2C_Address_3 ' <<< switching the active adapter this page documents
Print "Adapter #3"
LCD_I2C_Address_Current = LCD_I2C_Address_4
Print "Adapter #4"
wait 4 s
LCD_I2C_Address_Current = LCD_I2C_Address_1: CLS
LCD_I2C_Address_Current = LCD_I2C_Address_2: CLS
LCD_I2C_Address_Current = LCD_I2C_Address_3: CLS
LCD_I2C_Address_Current = LCD_I2C_Address_4: CLSKey line: LCD_I2C_Address_Current = LCD_I2C_Address_3 — writing to LCD_I2C_Address_Current redirects every subsequent LCD command to a different physical adapter, without needing four separate sets of LCD write commands.
See Also:
- LCD_IO 12 — the connection mode this technique applies to
- LCD_IO 12 Port Configuration — wiring the port pins for connection mode 12
