mLink Character LCDs (HCMODU0190A & HCMODU0190B)

mLink serial I2C modules
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mLink Character LCDs (HCMODU0190A & HCMODU0190B)

Post by admin » Tue Apr 26, 2022 10:02 am


The mLink Character LCDs are serial (I2C/IIC) LCD displays available in either 16 column by 2 row (16x2), or 20 column by 4 row (20x4) options. Because they use a standard I2C interface they are compatible with most microcontrollers including Arduino, are addressable (address can be changed in software), and only require 2 data pins for communication. Unlike standard serial or parallel character displays they require no configuration or setup to use them saving on development time and code size.

Text is displayed as a very clear white text on a blue backlight. The backlight's brightness level is fully programmable and can be set in 10% increments allowing you to dim the display or turn it completely off to save power. mLink modules are also compatible with other mLink or standard I2C modules allowing you to daisy-chain several different types of modules together using only the two I2C pins of your microcontroller.

For Arduino users you can use the mLink library (see below) to control any type of mLink module. The library has a very small memory footprint and only one single instance is needed to control multiple types of mLink modules. This makes it great for Arduinos with small amounts of memory and pin counts.

Module specifications:

Module code: 						HCMODU0190A (16x2 white text on blue backlight) 
								HCMODU0190B (20x4 white text on blue backlight)
Supply voltage (VDD): 				4.5V to 5.5V
Operating range (recommended):		0oC to 50oC
Display type (HCMODU0190A):			16x2 character alphanumeric LCD
Display type (HCMODU0190B):			20x4 character alphanumeric LCD
Current max (HCMODU0190A):			31mA (100% backlight, Vcc = 5V)
Current min(HCMODU0190A):			2mA (sleep)
Current max (HCMODU0190B):			46mA (100% backlight, Vcc = 5V)
Current min(HCMODU0190B):			2mA (sleep)
Interfaces:						I2C
I2C Interface speed: 					400kbits/s (fast mode)
I2C default address (HEX): 			0h56
Maximum number of modules: 			5 with pullups fitted, 112 with pullups removed*
HCMODU0190A dimensions (inc module):	80mm x 36mm x 19mm
HCMODU0190B dimensions (inc module):	98mm x 60mm x 19mm

*Note the maximum number of connected modules will depend on cable lengths and power requirements of each module. Do not exceed 5 mLink modules connected in series with all pullups fitted.

Arduino Connection Example:



Because the modules use an I2C interface this also means multiple modules can be controlled from a single Arduino I2C interface simply by daisy-chaining them together. Note to control multiple mLink modules of the same type requires changing the default I2C address of the additional modules. See mLink Library Quick Start Guide for how to do this.


Print some text example

Arduino Temperature & Humidity Example:

This sketch uses the mLink library to print some text to the display.

  1. #include "mLink.h"                      // Include the library
  3. mLink mLink;                            // Create an instance of the library
  5. #define I2C_ADD 0x56                    // Default I2C address
  8. void setup()
  9. {
  10.   mLink.init();                         // Initialise the library
  11. }
  13. void loop()
  14. {
  15.   mLink.cLCD_cursor(I2C_ADD, 5, 0);     // Set the cursor to col 5 row 0
  16.   mLink.cLCD_print(I2C_ADD, "Hello");   // Print something
  19.   mLink.cLCD_cursor(I2C_ADD, 5, 1);     // Set the cursor to col 5 row 1
  20.   mLink.cLCD_print(I2C_ADD, "World");   // Print something
  22.   while(1);
  23. }

Display a number example

Arduino Low Power Mode Example:

This sketch uses the mLink library to display a value representing the Arduino 'up time'
  1. #include "mLink.h"                          // Include the library
  3. mLink mLink;                                // Create an instance of the library
  5. #define I2C_ADD 0x56                        // Default I2C address
  7. float time;
  9. void setup()
  10. {
  11.   mLink.init();                             // Initialise the library
  13.   mLink.cLCD_clear(I2C_ADD)                 // Clear the screen
  15.   mLink.cLCD_print(I2C_ADD, "Uptime: ");    // Print some text
  16. }
  19. void loop()
  20. {
  21.   time = (float)millis() / 1000;            // Get the Arduinos 'up time' and conver it to seconds
  23.   mLink.cLCD_cursor(I2C_ADD, 10, 0);        // Set the cursor to col 10 row 0
  24.   mLink.cLCD_printFloat(I2C_ADD, time, 3);  // Print the uptime to 3 decimal places
  26.   delay(1);
  27. }


mLink Arduino library

mLink Library Quick Start Guide For Arduino Users ... _Guide.pdf

mLink Library Reference Guide For The Character LCD Sensor Modules ... _Guide.pdf

mLink Specifications and Register Map For The Character LCD Modules ... er_Map.pdf

Libraries, example code, and diagrams are provided as an additional free service by Hobby Components and are not sold as part of this product. We do no provide any guarantees or warranties as to their accuracy or fitness for purpose.

Descriptions and diagrams on this page are copyright Hobby Components Ltd and may not be reproduced without permission.

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