SSD1306 128x64 SPI OLED Display: Difference between revisions

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  RES#  This pin is reset signal input. When the pin is pulled LOW, initialization of the chip is executed.
  RES#  This pin is reset signal input. When the pin is pulled LOW, initialization of the chip is executed.
         Keep this pin HIGH (i.e. connect to VDD) during normal operation.
         Keep this pin HIGH (i.e. connect to VDD) during normal operation.
  D/C#  This is Data/Command control pin. When it is pulled HIGH (i.e. connect to VDD),
  D/C#  This is Data/Command control pin. When LOW, it indicates a command to be sent to the command register.
        the signals at D[7:0] are treated as data. When it is pulled LOW, the signals at D[7:0]
        When HIGH, it indicates data.
        will be transferred to the command register.
         In I2C mode, this pin acts as SA0 for slave address selection.
         In I2C mode, this pin acts as SA0 for slave address selection.
         When 3-wire serial interface is selected, this pin must be connected to VSS.
         When 3-wire serial interface is selected, this pin must be tied low (connected to VSS).
        For detail relationship to MCU interface signals, please refer to the Timing Characteristics Diagrams:
        Figure 13-1 to Figure 13-5. E (RD#) I When interfacing to a 6800-series micro
  CS#  This pin is the chip select input. (active LOW).
  CS#  This pin is the chip select input. (active LOW).
   
   

Revision as of 19:57, 30 December 2020

Hardware 

These displays use the SSD1306 controller: https://cdn-shop.adafruit.com/datasheets/SSD1306.pdf

The following is from the SSD1306.pfd document: 

8.1.3 MCU Serial Interface (4-wire SPI)
The 4-wire serial interface consists of serial clock: SCLK, serial data: SDIN (MOSI), D/C#, CS#.
In 4-wire SPI mode, D0 is used for SCLK signal, D1 is used for MOSI. For the unused data pins, D2 should be left open.
The pins from D3 to D7, E and R/W# (WR#)# can be connected to an external ground.

Table 8-4 : Control pins of 4-wire Serial interface
Function	E(RD#)	R/W#(WR#)	CS#	D/C#	D0
Write command	Tie LOW	Tie LOW	L	L	↑
Write data	Tie LOW	Tie LOW	L	H	↑
Note
(1) H stands for HIGH signal
(2) L stands for LOW signal

RES#   This pin is reset signal input. When the pin is pulled LOW, initialization of the chip is executed.
       Keep this pin HIGH (i.e. connect to VDD) during normal operation.
D/C#   This is Data/Command control pin. When LOW, it indicates a command to be sent to the command register. 
       When HIGH, it indicates data.
       In I2C mode, this pin acts as SA0 for slave address selection.
       When 3-wire serial interface is selected, this pin must be tied low (connected to VSS).
CS#  This pin is the chip select input. (active LOW).

NOTE: This device uses SPI mode 0.

For this exercise, I used the SPI (4 wire) Hardware interface, with reset (RES#) added. (I don't believe MISO is used.)
According to the datasheet, the maximum SPI clock frequency is 10MHz. 

Connections
Board	       MOSI    MISO	SCK	RES#	CS#	D/C#
Arduino UNO	11	12	13	8	7	6

Software 

For Arduino, the Adafruit SSD1306 library, version 2.4.2, works very well.

Additional Resources 

https://learn.adafruit.com/monochrome-oled-breakouts/wiring-128x32-spi-oled-display
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