This is a quick tutorial for our 128x64 and 128x32 pixel monochrome OLED displays. These displays are small, only about 1" diagonal, but very readable due to the high contrast of an OLED display. Each OLED display is made of 128x64 or 128x32 individual white OLEDs, each one is turned on or off by the controller chip. Because the display makes its own light, no backlight is required. This reduces the power required to run the OLED and is why the display has such high contrast; we really like this miniature display for its crispness!
The driver chip, SSD1306 can communicate in multiple ways including I2C, SPI and 8-bit parallel. However, only the 128x64 display has all these interfaces available. For the 128x32 OLED, only SPI is available. Frankly, we prefer SPI since its the most flexible and uses a small number of I/O pins so our example code and wiring diagram will use that.
OLED Power Requirements
The OLED and driver require a 3.3V power supply and 3.3V logic levels for communication. The power requirements depend a little on how much of the display is lit but on average the display uses about 20mA from the 3.3V supply. Built into the OLED driver is a simple switch-cap charge pump that turns 3.3v-5v into a high voltage drive for the OLEDs. You can run the entire display off of one 3.3V supply or use 3.3V for the chip power and up to 4.5V for the OLED charge pump or 3.3V for the chip power and a 7-9V supply directly into the OLED high voltage pin.
5V- ready 128x64 and 128x32 OLEDs
Unless you have the older v1 128x64 OLED, you can rest assured that your OLED is 5V ready. All 1.3" 128x64 and the small 128x32 SPI and I2C are 5V ready, if you have a v2 0.96" 128x64 OLED with the 5V ready mark on the front, it's also 5V safe. If you have an older 0.96" OLED (see below) you'll need to take extra care when wiring it to a 5V micontroller. The OLED is designed to be 5V compatible so you can power it with 3-5V and the onboard regulator will take care of the rest.
All OLEDs are safe to use with 3.3V logic and power.
Simply connect GND to ground, and Vin to a 3 to 5V power supply. There will be a 3.3V output on the 3Vo pin in case you want a regulated 3.3V supply for something else.
0.96" 128x64 OLED
The older 0.96" 128x64 OLED is a little more complex to get running as it is not 5V compatible by default, so you have to provide it with 3.3V power.
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VDD is the 3.3V logic power. This must be 3 or 3.3V
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VBAT is the input to the charge pump. If you use the charge pump, this must be 3.3V to 4.2V
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VCC is the high voltage OLED pin. If you're using the internal charge pump, this must be left unconnected. If you're not using the charge pump, connect this to a 7-9V DC power supply.
For most users, we suggest connecting VDD and VBAT together to 3.3V and then leaving VCC unconnected.
For all of the different kinds of small OLED monochrome displays, you'll need to install the Arduino libraries. The code we have is for any kind of Arduino, if you're using a different microcontroller, the code is pretty simple to adapt, the interface we use is basic bit-twiddling SPI or I2C
Install Adafruit SSD1306 Library
Start by installing the support library for the OLED display, you'll need it to talk to the OLED controller chip. We have the Adafruit SSD1306 library repository on GitHub if you're interested in looking at the code.
Start by downloading the library. You can do that by visiting the github repo and manually downloading or, easier, just click this button to download the zip:
Rename the uncompressed folder Adafruit_SSD1306 and check that the Adafruit_SSD1306 folder contains Adafruit_SSD1306.cpp and Adafruit_SSD1306.h
Place the Adafruit_SSD1306 library folder your arduinosketchfolder/libraries/ folder.
You may need to create the libraries subfolder if its your first library. Restart the IDE.We also have a great tutorial on Arduino library installation at:
http://learn.adafruit.com/adafruit-all-about-arduino-libraries-install-use
Rename the uncompressed folder Adafruit_GFX and check that the Adafruit_GFX folder contains Adafruit_GFX.cpp and Adafruit_GFX.h
Place the Adafruit_GFX library folder your arduinosketchfolder/libraries/ folder like you did with the SSD1306 library
Run Demo!
After installing the Adafruit_SSD1306 and Adafruit_GFX library, restart the Arduino IDE. You should now be able to access the sample code by navigating through menus in this order: File→Sketchbook→Libraries→Adafruit_SSD1306→SSD1306...
The library cannot determine the screen size via software. You have to specify it in the header file. Go into the library folder and open the file Adafruit_SSD1306.h. Toward the top you'll see a section of comments that tell how how to edit the file for different kinds of display.
Create Bitmaps
You can create bitmaps to display easily with the
LCD assistant software. First make your image using any kind of graphics software such as photoshop or Paint and save as a
Monochrome Bitmap (bmp)
Select the following options (You might also want to try Horizontal if Vertical is not coming out right)
and import your monochrome bitmap image. Save the output to a cpp file
You can use the output directly with our example code
Solder Header
Before you start wiring, a strip of header must be soldered onto the OLED. It is not possible to "press-fit" the header, it must be attached!
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Start by placing an 8-pin piece of header with the long ends down into a breadboard for stability |
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Place the OLED on top so all the short ends of the header stick thru the header pads |
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Finish by soldering each of the 8 pins to the 8 pads! |
I2C or SPI
The nice thing about the 128x64 OLEDs is that they can be used with I2C (+ a reset line) or SPI. SPI is generally faster than I2C but uses more pins. It's also easier for some microcontrollers to use SPI. Anyways, you can use either one with this display
Using with I2C
The display can be used with any I2C microcontroller. Because the I2C interface is for 'writing' to the display only, you'll still have to buffer the entire 512 byte frame in the microcontroller RAM - you can't read data from the OLED (even though I2C is a bidirectional protocol).
To start, you'll need to solder the two jumpers on the back of the OLED.
Both must be soldered 'closed' for I2C to work!
Finally, connect the pins to your Arduino
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GND goes to ground
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Vin goes to 5V
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Data to I2C SDA (on the Uno, this is A4 on the Mega it is 20 and on the Leonardo digital 2)
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Clk to I2C SCL (on the Uno, this is A5 on the Mega it is 21 and on the Leonardo digital 3)
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RST to digital 4 (you can change this pin in the code, later)
This matches the example code we have written. Once you get this working, you can try a different Reset pin (you can't change the SCA and SCL pins).
Finally you can run the
File→Sketchbook→Libraries→Adafruit_SSD1306→SSD1306_128x64_i2c example
Using with SPI
The breakouts are ready for SPI by default, but if you used them for I2C at some point, you'll need to remove the solder jumpers. Use wick or a solder sucker to make sure both are clear!
Finally, connect the pins to your Arduino -
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GND goes to ground
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Vin goes to 5V
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DATA to digital 9
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CLK to digital 10
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D/C to digital 11
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RST to digital 13
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CS to digital 12
(Note: If using the display with other SPI devices, D/C, CLK and DAT may be shared, but CS must be unique for each device.)
This matches the example code we have written. Once you get this working, you can try another set of pins.
Finally you can run the
File→Sketchbook→Libraries→Adafruit_SSD1306→SSD1306_128x64_spi example
128x32 SPI OLED
The 128x32 SPI OLED is very easy to get up and running because it has built in level shifting. First up, take a piece of 0.1" header 8 pins long.
Plug the header long end down into a breadboard and place the OLED on top. Solder the short pins into the OLED PCB.
Finally, connect the pins to your Arduino - GND goes to ground, Vin goes to 5V, DATA to digital 9, CLK to digital 10, D/C to digital 11, RST to digital 13 and finally CS to digital 12.
(Note: If using the display with other SPI devices, D/C, CLK and DAT may be shared, but CS must be unique for each device.)
This matches the example code we have written. Once you get this working, you can try another set of pins.
Finally you can run the File→Sketchbook→Libraries→Adafruit_SSD1306→SSD1306_128x32_SPI example
If you're using the 128x32 OLED, be sure to uncomment the "#define SSD1306_128_32" in the top of Adafruit_SSD1306.h to change the buffer size
This wiring diagram is only for the older 0.96" OLED that comes with a level shifter chip. If you did not get a level shifter chip, you have a V2.0 so please check out the other wiring tutorial!
128x64 Version 1.0 OLED
The version 1 128x64 OLED runs at 3.3V and does not have a built in level shifter so you'll need to use a level shifting chip to use with a 5V microcontroller. The following will assume that is the case. If you're running a 3.3V microcontroller system, you can skip the level shifter.
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We'll assume you want to use this in a breadboard, take a piece of 0.1" header 10 pins long. |
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Place the header in a breadboard and then place the left hand side of the OLED on top. |
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And solder the pins |
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We'll be using the internal charge pump so connect VDD and VBAT together (they will connect to 3.3V). GND goes to ground.
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Place a CD4050 level shifter chip so pin one is at the top. |
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Connect pin 10 to D/C pin 12 to CLK (SPI clock) and pin 15 to DAT (SPI data).
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Connect pin 2 to RES (reset) and pin 4 to CS (chip select). Pin 1 goes to 3.3V and pin 8 to ground.
(Note: If using the display with other SPI devices, D/C, CLK and DAT may be shared, but CS must be unique for each device.)
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You can connect the inputs of the level shifter to any pins you want but in this case we connected digital I/O 13 to pin 3 of the level shifter, 12 to pin 5, 11 to pin 9, 10 to pin 11 and 9 to pin 14. This matches the example code we have written. Once you get this working, you can try another set of pins.
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Software
You can download our SSD1306 OLED display Arduino library from github which comes with example code. The library can print text, bitmaps, pixels, rectangles, circles and lines. It uses 1K of RAM since it needs to buffer the entire display but its very fast! The code is simple to adapt to any other microcontroller. You'll also have to install the Adafruit GFX graphics core library at this github repo and install it after you've gotten the OLED driver library.
Datasheets
Files
Schematic & Fabrication Print for 0.96" OLED
Schematic & Fabrication Print for 1.3" OLED
Schematic & Fabrication Print for 0.91" 128x32 I2C
Schematic & Fabrication Print for 0.91" 128x32 SPI
