mxUnifiedPCD8544_Nokia_5110_LCD
mxUnifiedIO device library for Arduino. Device specific driver for the PCD8544 Nokia 5110 LCD display, derived from the Adafruit GFX library. Use SPI shift registers or I2C I/O expanders via the mxUnifiedIO API.
DESCRIPTION
This is a library for the Monochrome Nokia 5110 LCD Displays
These displays normally use SPI to communicate. 3 to 5 data-pins are required to interface with the MCU. When using the minimum of three data-pins (DC/DIN/CLK), the remaining pins are fixed. By using the mxUnifiedPCF8574 library for an I2C interface or the mxUnified74HC595 library for shift registers, the display can be connected to share the I2C bus (only two pins) or the SPI pins (three wires).
This library is based on the Adafruit PCD8544 Nokia 5110 LCD library, but instead of directly using SPI it allows the display to be driven via the expanded pins of an I2C I/O expander or a shift register. Please note that generating software SPI using the expanded pins of a serial driven I/O expander or shiftregister is notably slower than a direct connection. The pcd_test example has been adapted to include measurements of time spent per display test. You can use these to compare the different ways to drive the display.
Using SPI shift register
The (shared) SPI bus requires three data-lines to connect one or more shift registers (SS, MOSI and SCK). On the Arduino UNO, Nano and Pro Mini, the pins for (fast) hardware SPI are D10, D12 and D13. On the ESP8266 the default SPI pins are GPIO15, GPIO13 and GPIO14. When using (slower) software SPI others can be selected too.
Using I2C I/O expander
The (shared) I2C bus only requires two data-lines (SDA and SCL). On the Arduino UNO, Nano and Pro Mini, these can be found on pins A4 and A5. On the ESP8266 the default pins are GPIO4 and GPIO5, but others can be selected too.
The I2C data is expanded to the recommended 5 pins using the PCF8574 I2C I/O expander. A very affordable and abundantly available board that features a PCF8574 chip is the I2C backpack module, whihc is most commonly used as interface to the 1602 and 2004 character LCD display modules. Using only slightly different connections this interface board can be used to connect the 48x84 Nokia 5110 dot-matrix LCD display module.
Module Pinout
Nokia 5110 LCD Display module:
+------------------+
| ........ |
| +--------------+ |
| +--------------+ |
| | | |
| | | |
| | | |
| | | |
| +--------------+ |
| ........ |
+------------------+
12345678
Pin Description
1. RST--------- reset
2. CE---------- chip selection
3. DC---------- data/commands choice
4. DIN--------- serial data line
5. CLK--------- serial Clock Speed
6. 3.3V-------- VCC
7. LIGHT------- backlight control terminal
8. GND--------- power negative
PCF8574 I2C LCD driver:
+---------------------+
-SCL-+ ::: +---+ |
-SCA-+ +-+ |PCF| ''': LED+-
-VCC-+ |*| | | ..- jmp+-
-GND-+ +-+ +---+ |
+---------------------+
1234567890123456
||||||||||||||||
Pin Description
1. GND
2. VCC
3. Contrast (adjustable VCC->Pot->Pin3)
4. P0
5. P1
6. P2
7. not connected
8. not connected
9. not connected
10. not connected
11. P4
12. P5
13. P6
14. P7
15. VCC (for LED)
16. P3 (connected via LED jumper to J3Y (=S8050) transistor, sink)
See the included example for suggested connections of the display module to the I2C LCD driver interface.
CREDITS
- Credits to Adafruit for creating the original PCD8544 library and the required Adafruit GFX library. Adafruit invests time and resources providing this open source code, please support Adafruit and open-source hardware by purchasing products from Adafruit!
Pick a Nokia 5110 display up today in the adafruit shop! ------> http://www.adafruit.com/products/338
Original version written by Limor Fried/Ladyada for Adafruit Industries. BSD license, check license.txt for more information All text above must be included in any redistribution.
-
Credits to Rob Tillaart for creating the PCF8574 library. Check out his large collection of Arduino libraries at https://github.com/RobTillaart/Arduino
-
Modified library by Maxint R&D 2017. BSD license applies. See below for more information .
INSTALLATION
Download the required libraries (see links below). Use the Arduino IDE to add the .ZIP library file via the menu. Alternatively copy all library files into a folder under your /libraries/ folder and restart the IDE.
You will also have to install the Adafruit GFX Graphics core library which does all the circles, text, rectangles, etc; as well as the mxUnifiedIO library. Also install either the mxUnifiedPCF8574 library or the mxUnified74HC595 librraries, which are used to drive the PCD8544 LCD chip.
See the included examples to learn more about using this library.
TROUBLESHOOTING TIPS
- Use the I2C scanner sketch to see if the PCF8574 I2C LCD driver is properly connected and responding.
- Test the Nokia 5110 module using the SPI connections and the original library and pcdtest example.
- Check if all data-pins between display and interface modules are properly connected, according the pins as defined in your sketch.
- Use a multimeter to check pin voltages. Note: most Nokia 5110 and PCF8574 modules are both 3.3V and 5V complient. However, the contrast level on some 5110 modules needs to be higher when powered by 3.3V.
- This library was tested to work fine on ESP8266, ATmega328 and ATmega168. However, the ATmega168 is limited in memory (only 1K RAM and 16K flash). On the 168 the HC595_pcd_test example worked only when disabling bitmap and text testing. Unfortunately for I2C more memory is required. The Adafruit based library is just too large for that MCU. To use the Nokia display via I2C on the ATmega168, the Sparkfun code may prove more succesful.
LINKS
Required libraries:
- This library:
- Supporting libraries:
- Adafruit GFX Library:
For reference:
- Adafruit tutorials:
- Arduino I2C scanner sketches:
- The original Adafruit PCD8544 Nokia 5110 LCD SPI library:
LICENSE
This library inherits the BSD license from the original library which limits the usage of this library to specific terms. Read license.txt for more information.