LCD mini click

LCD mini click displays 2×16 monochrome characters on an LMB162XFW LCD display. It features the MCP23S17 port expander and the MCP4161 digital potentiometer, both from Microchip. LCD mini click is designed to communicate with both 3.3V or 5V capable MCUs. The logic voltage level selection is done by the PWR SEL onboard SMD jumper. The 5V rail from the mikroBUS™ is used directly for powering up the included LCD screen. The click board™ communicates with the target microcontroller over the SPI interface and the following pins on the mikroBUS™ line: PWM, INT, RST, AN.

LCD and backlight control

The PWM pin onboard the LCD mini click is used for backlight control. While the digital potentiometer is used for contrast adjustments.

2×16 LCD display features

2×16 LDC displays are ideal for displaying short messages and numbers. They can display 16 characters per one line, 32 in total. The 5×8 dot font displays characters, symbols, and numbers clearly and vividly.

Specifications

Pinout diagram

This table shows how the pinout on LCD mini click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
Digipot CS	CS2	1	AN	PWM	16	PWM	Pulse-Width Modulation
Reset for the port expander	RST	2	RST	INT	15	INT	INT from the port expander
SPI chip select	CS	3	CS	RX	14	NC
SPI clock	SCK	4	SCK	TX	13	NC
SPI Master Input Slave Output	MISO	5	MISO	SDA	12	NC
SPI Master Output Slave Input	MOSI	6	MOSI	SDA	11	NC
Power supply	+3.3V	7	3.3V	5V	10	+5V	Power supply
Ground	GND	8	GND	GND	9	GND	Ground

Programming

The demo shows how to use the SPI LCD library to communicate with the LCD (with HD44780 compliant controllers) in 4-bit mode via the SPI interface. It also uses the PWM for the backlight and the on board digital potentiometer, for controlling display contrast, which can be accessed through SPI. The demo iterates through all the values for the backlight and the contrast intensity.

Code snippet

The main function of the demo.

01 void main()
02 {
03     system_init();
04 
05     SPI_Lcd_Out(1, 6, "mikroE");
06     SPI_Lcd_Out(2, 2, "LCD mini click");
07 
08     set_bcklight(0xFF);
09     set_contrast(0xDF);
10 
11     Delay_ms(5000);
12 
13     while (1)
14     {
15         set_bcklight(value);
16         set_contrast(value);
17 
18         value++;
19         delay_ms(40);
20     }
21 }