SPI Lcd Library

The mikroC PRO for PIC32 provides a library for communication with Lcd (with HD44780 compliant controllers) in 4-bit mode via SPI interface.

Important :

When using this library with PIC32 family MCUs be aware of their voltage incompatibility with certain number of Lcd modules.
So, additional external power supply for these modules may be required.
Library uses the SPI module for communication. The user must initialize the appropriate SPI module before using the SPI Lcd Library.
For MCUs with multiple SPI modules it is possible to initialize all of them and then switch by using the SPI_Set_Active() routine. See the SPI Library functions.
This Library is designed to work with the mikroElektronika's Serial Lcd Adapter Board pinout, see schematic at the bottom of this page for details.

Library Dependency Tree

External dependencies of SPI Lcd Library

The implementation of SPI Lcd Library routines is based on Port Expander Library routines.

External dependencies are the same as Port Expander Library external dependencies.

SPI_Lcd_Config

Prototype	void SPI_Lcd_Config(char DeviceAddress);
Description	Initializes the Lcd module via SPI interface.
Parameters	`DeviceAddress:` SPI expander hardware address, see schematic at the bottom of this page
Returns	Nothing.
Requires	Global variables : `SPExpanderCS`: Chip Select line `SPExpanderRST`: Reset line `SPExpanderCS_Direction`: Direction of the Chip Select pin `SPExpanderRST_Direction`: Direction of the Reset pin must be defined before using this function. The SPI module needs to be initialized. See SPIx_Init and SPIx_Init_Advanced routines.
Example	// Port Expander module connections sbit SPExpanderRST at LATF0_bit; sbit SPExpanderCS at LATF1_bit; sbit SPExpanderRST_Direction at TRISF0_bit; sbit SPExpanderCS_Direction at TRISF1_bit; // End Port Expander module connections // If Port Expander Library uses SPI1 module SPI1_Init(); // Initialize SPI module used with PortExpander SPI_Lcd_Config(0); // initialize Lcd over SPI interface
Notes	None.

SPI_Lcd_Out

Prototype	void SPI_Lcd_Out(char row, char column, char *text);
Description	Prints text on the Lcd starting from specified position. Both string variables and literals can be passed as a text.
Parameters	`row:` starting position row number `column:` starting position column number `text:` text to be written
Returns	Nothing.
Requires	Lcd needs to be initialized for SPI communication, see SPI_Lcd_Config routine.
Example	// Write text "Hello!" on Lcd starting from row 1, column 3: SPI_Lcd_Out(1, 3, "Hello!");
Notes	None.

SPI_Lcd_Out_Cp

Prototype	void SPI_Lcd_Out_CP(char *text);
Description	Prints text on the Lcd at current cursor position. Both string variables and literals can be passed as a text.
Parameters	`text:` text to be written
Returns	Nothing.
Requires	Lcd needs to be initialized for SPI communication, see SPI_Lcd_Config routine.
Example	// Write text "Here!" at current cursor position: SPI_Lcd_Out_CP("Here!");
Notes	None.

SPI_Lcd_Chr

Prototype	void SPI_Lcd_Chr(char Row, char Column, char Out_Char);
Description	Prints character on Lcd at specified position. Both variables and literals can be passed as character.
Parameters	`Row:` writing position row number `Column:` writing position column number `Out_Char:` character to be written
Returns	Nothing.
Requires	Lcd needs to be initialized for SPI communication, see SPI_Lcd_Config routine.
Example	// Write character "i" at row 2, column 3: SPI_Lcd_Chr(2, 3, 'i');
Notes	None.

SPI_Lcd_Chr_Cp

Prototype	void SPI_Lcd_Chr_CP(char Out_Char);
Description	Prints character on Lcd at current cursor position. Both variables and literals can be passed as character.
Parameters	`Out_Char:` character to be written
Returns	Nothing.
Requires	Lcd needs to be initialized for SPI communication, see SPI_Lcd_Config routine.
Example	// Write character "e" at current cursor position: SPI_Lcd_Chr_Cp('e');
Notes	None.

SPI_Lcd_Cmd

Prototype	void SPI_Lcd_Cmd(char out_char);
Description	Sends command to Lcd.
Parameters	`out_char:` command to be sent
Returns	Nothing.
Requires	Lcd needs to be initialized for SPI communication, see SPI_Lcd_Config routine.
Example	// Clear Lcd display: SPI_Lcd_Cmd(_LCD_CLEAR);
Notes	Predefined constants can be passed to the routine, see Available SPI Lcd Commands.

Available SPI Lcd Commands

SPI Lcd Command	Purpose
_LCD_FIRST_ROW	Move cursor to the 1st row
_LCD_SECOND_ROW	Move cursor to the 2nd row
_LCD_THIRD_ROW	Move cursor to the 3rd row
_LCD_FOURTH_ROW	Move cursor to the 4th row
_LCD_CLEAR	Clear display
_LCD_RETURN_HOME	Return cursor to home position, returns a shifted display to its original position. Display data RAM is unaffected.
_LCD_CURSOR_OFF	Turn off cursor
_LCD_UNDERLINE_ON	Underline cursor on
_LCD_BLINK_CURSOR_ON	Blink cursor on
_LCD_MOVE_CURSOR_LEFT	Move cursor left without changing display data RAM
_LCD_MOVE_CURSOR_RIGHT	Move cursor right without changing display data RAM
_LCD_TURN_ON	Turn Lcd display on
_LCD_TURN_OFF	Turn Lcd display off
_LCD_SHIFT_LEFT	Shift display left without changing display data RAM
_LCD_SHIFT_RIGHT	Shift display right without changing display data RAM

Library Example

Default Pin Configuration

Use SPI_Lcd_Init for default pin settings (see the first figure below).

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char *text = "mikroElektronika";

// Port Expander module connections
sbit  SPExpanderRST at LATD8_bit;
sbit  SPExpanderCS  at LATD9_bit;
sbit  SPExpanderRST_Direction at TRISD8_bit;
sbit  SPExpanderCS_Direction  at TRISD9_bit;
// End Port Expander module connections

char i;                              // Loop variable

void Move_Delay() {                  // Function used for text moving
  Delay_ms(500);                     // You can change the moving speed here
}

void main() {

  CHECON = 0x32;
  AD1PCFG = 0xFFFF;                                       // Configure AN pins as digital

  // If Port Expander Library uses SPI2 module
  // Initialize SPI module used with PortExpander
  SPI2_Init_Advanced(_SPI_MASTER,_SPI_8_BIT, 4, _SPI_SS_DISABLE,_SPI_DATA_SAMPLE_MIDDLE,_SPI_CLK_IDLE_LOW,_SPI_ACTIVE_2_IDLE);

  SPI_Lcd_Config(0);                     // Initialize Lcd over SPI interface
  SPI_Lcd_Cmd(_LCD_CLEAR);               // Clear display
  SPI_Lcd_Cmd(_LCD_CURSOR_OFF);          // Turn cursor off
  SPI_Lcd_Out(1,6, "mikroE");            // Print text to Lcd, 1st row, 6th column
  SPI_Lcd_Chr_CP('!');                   // Append '!'
  SPI_Lcd_Out(2,1, text);                // Print text to Lcd, 2nd row, 1st column

  // SPI_Lcd_Out(3,1,"mikroE");          // For Lcd with more than two rows
  // SPI_Lcd_Out(4,15,"mikroE");         // For Lcd with more than two rows

  Delay_ms(2000);

  // Moving text
  for(i=0; i<4; i++) {                   // Move text to the right 4 times
    SPI_Lcd_Cmd(_LCD_SHIFT_RIGHT);
    Move_Delay();
  }

  while(1) {                             // Endless loop
    for(i=0; i<8; i++) {                 // Move text to the left 7 times
      SPI_Lcd_Cmd(_LCD_SHIFT_LEFT);
      Move_Delay();
    }

    for(i=0; i<8; i++) {                 // Move text to the right 7 times
      SPI_Lcd_Cmd(_LCD_SHIFT_RIGHT);
      Move_Delay();
    }
  }

}

Lcd HW connection by default initialization (using SPI_Lcd_Init)

Lcd HW connection by default initialization (using SPI_Lcd_Init)

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