I2C/SPI: physical interface functions

i2c/spi initialization functions for different platforms More...

Classes
struct	ssd1306_interface_t

Macros
#define	SSD1306_SA   0x3C
#define	ssd1306_dcQuickSwitch   ssd1306_intf.spi
#define	ssd1306_startTransmission   ssd1306_intf.start
#define	ssd1306_endTransmission   ssd1306_intf.stop
#define	ssd1306_sendByte   ssd1306_intf.send
#define	ssd1306_sendBytes   ssd1306_intf.send_buffer
#define	ssd1306_closeInterface   ssd1306_intf.close

Functions
void	ssd1306_i2cInit (void)
void	ssd1306_i2cInitEx (int8_t scl, int8_t sda, int8_t sa)
void	ssd1306_i2cInit_Embedded (int8_t scl, int8_t sda, uint8_t sa)
void	ssd1306_i2cConfigure_Twi (uint8_t arg)
void	ssd1306_i2cInit_Twi (uint8_t sa)
void	ssd1306_spiInit (int8_t cesPin, int8_t dcPin)
void	ssd1306_spiDataMode (uint8_t mode)
void	ssd1306_spiInit_avr (int8_t cesPin, int8_t dcPin)
void	ssd1306_spiInit_Usi (int8_t cesPin, int8_t dcPin)
void	ssd1306_sendCommand (uint8_t command)
void	ssd1306_commandStart (void)
void	ssd1306_dataStart (void)
void	ssd1306_uartInit_Builtin (uint32_t baud)

Variables
int8_t	s_ssd1306_cs
int8_t	s_ssd1306_dc
uint32_t	s_ssd1306_spi_clock
ssd1306_interface_t	ssd1306_intf

Detailed Description

i2c/spi initialization functions for different platforms

This group of API functions serves to prepare the library to work via specific hardware interface. There are a bunch of functions for different platforms. In general display initialization goes in two steps: hardware interface initialization, and then display driver initialization. But there are functions, which combine 2 steps in single call: ssd1306_128x64_i2c_initEx(), ssd1351_128x128_spi_init(), etc.

Macro Definition Documentation

ssd1306_closeInterface

#define ssd1306_closeInterface   ssd1306_intf.close

Deprecated

Definition at line 124 of file ssd1306_interface.h.

ssd1306_dcQuickSwitch

#define ssd1306_dcQuickSwitch   ssd1306_intf.spi

Deprecated

Definition at line 99 of file ssd1306_interface.h.

ssd1306_endTransmission

#define ssd1306_endTransmission   ssd1306_intf.stop

Deprecated

Definition at line 109 of file ssd1306_interface.h.

SSD1306_SA

#define SSD1306_SA   0x3C

SSD1306_SA defines default i2c address of LCD display. Please, check your device. If you LCD device has different address, you can set different one via ssd1306_i2cInit_Wire() or ssd1306_i2cInit_Embedded() functions. Write command will be SSD1306_SA<<1 and read will be SSD1306_SA<<1 | 1

Definition at line 47 of file ssd1306_i2c_conf.h.

ssd1306_sendByte

#define ssd1306_sendByte   ssd1306_intf.send

Deprecated

Definition at line 114 of file ssd1306_interface.h.

ssd1306_sendBytes

#define ssd1306_sendBytes   ssd1306_intf.send_buffer

Deprecated

Definition at line 119 of file ssd1306_interface.h.

ssd1306_startTransmission

#define ssd1306_startTransmission   ssd1306_intf.start

Deprecated

Definition at line 104 of file ssd1306_interface.h.

Function Documentation

ssd1306_commandStart()

void ssd1306_commandStart

(

void

)

Starts transaction for sending commands.

Definition at line 36 of file ssd1306_interface.c.

ssd1306_dataStart()

void ssd1306_dataStart

(

void

)

Starts transaction for sending bitmap data.

Definition at line 45 of file ssd1306_interface.c.

ssd1306_i2cConfigure_Twi()

void ssd1306_i2cConfigure_Twi

(

uint8_t

arg

)

Configures standard TWI AVR module (at 400kHz). This function is called by ssd1306_i2cInit().

Parameters

arg	- has no meaning for now. Should be zero

Note

scl and sda pins depend on used hardware.

Definition at line 111 of file ssd1306_i2c_twi.c.

ssd1306_i2cInit()

void ssd1306_i2cInit

(

void

)

Inits display interface to use i2c bus. The function automatically selects available type of i2c implementation

1. Wire library
2. sw i2c implementation In case of using Wire library this function calls Wire.begin() and sets speed to fast i2c (400kHz). If you prefer to use your own Wire settings or avoid reinitializing of Wire library, please use ssd1306_i2cInit_Wire(). If you want to use embedded i2c (if it is supported), use ssd1306_i2cInit_Embedded().

Note

: after call to this function you need to initialize lcd display.

Definition at line 45 of file ssd1306_i2c.c.

ssd1306_i2cInit_Embedded()

void ssd1306_i2cInit_Embedded	(	int8_t	scl,
		int8_t	sda,
		uint8_t	sa
	)

Initializes software implementation of i2c. If you do not know i2c parameters, try ssd1306_i2cInit_Embedded(0,0,0).

Warning

the function disables interrupts.

Parameters

scl	- i2c clock pin. Use -1 if you don't need to change default pin number
sda	- i2c data pin. Use -1 if you don't need to change default pin number
sa	- i2c address of lcd display. Use 0 to leave default

Note

: after call to this function you need to initialize lcd display.

Definition at line 178 of file ssd1306_i2c_embedded.c.

ssd1306_i2cInit_Twi()

void ssd1306_i2cInit_Twi

(

uint8_t

sa

)

Initializes ssd1306 library to use TWI AVR module for i2c. If you do not know i2c parameters, try ssd1306_i2cInit_Twi(0). SCL and SDA pins depend on platform.

Parameters

sa	- i2c address of lcd display. Use 0 to leave default

Note

: after call to this function you need to initialize lcd display.

Definition at line 160 of file ssd1306_i2c_twi.c.

ssd1306_i2cInitEx()

void ssd1306_i2cInitEx	(	int8_t	scl,
		int8_t	sda,
		int8_t	sa
	)

Inits display interface to use i2c bus. The function automatically selects available type of i2c implementation

1. Wire library
2. sw i2c implementation In case of using Wire library this function calls Wire.begin() and sets speed to fast i2c (400kHz). If you prefer to use your own Wire settings or avoid reinitializing of Wire library, please use ssd1306_i2cInit_Wire(). If you want to use embedded i2c (if it is supported), use ssd1306_i2cInit_Embedded().

Parameters

scl	- i2c clock pin. Use -1 if you don't need to change default pin number
sda	- i2c data pin. Use -1 if you don't need to change default pin number
sa	- i2c address of lcd display. Use 0 to leave default

Note

scl and sda parameters depend on used hardware. For many hardware boards these parameters do not have any effect. ESP8266 allows to specify these parameters

scl and sda for Linux systems should be the same, and should contain i2c bus id.

: after call to this function you need to initialize lcd display.

Definition at line 28 of file ssd1306_i2c.c.

ssd1306_sendCommand()

void ssd1306_sendCommand

(

uint8_t

command

)

Sends command to SSD1306 device: includes initiating of transaction, sending data and completing transaction.

Parameters

command

- command to send

Definition at line 54 of file ssd1306_interface.c.

ssd1306_spiDataMode()

void ssd1306_spiDataMode

(

uint8_t

mode

)

Switches spi to data(1) or command(0) mode.

Parameters

mode	- 1 data mode 0 command mode

Definition at line 50 of file ssd1306_spi.c.

ssd1306_spiInit()

void ssd1306_spiInit	(	int8_t	cesPin,
		int8_t	dcPin
	)

Inits lcd interface to use hardware spi for communication. The function automatically selects available type of spi implementation

1. SPI library (ssd1306_spiInit_hw())

   Parameters

   cesPin	- pin, controlling chip enable of LCD
   dcPin	- pin, controlling data/command mode of LCD

   Note

   : after call to this function you need to initialize lcd display.

Definition at line 37 of file ssd1306_spi.c.

ssd1306_spiInit_avr()

void ssd1306_spiInit_avr	(	int8_t	cesPin,
		int8_t	dcPin
	)

Inits lcd interface to use hardware SPI for communication (SPI.h library). It uses standard MOSI, SCLK pins to send data to LCD.

Parameters

cesPin	- pin, controlling chip enable of LCD
dcPin	- pin, controlling data/command mode of LCD

Note

: after call to this function you need to initialize lcd display.

Definition at line 133 of file ssd1306_spi_avr.c.

ssd1306_spiInit_Usi()

void ssd1306_spiInit_Usi	(	int8_t	cesPin,
		int8_t	dcPin
	)

Inits lcd interface to use USI for SPI communication. It uses standard USI CLK, USI DO, USI DI pins to send data to LCD.

Parameters

cesPin	- pin, controlling chip enable of LCD
dcPin	- pin, controlling data/command mode of LCD

Note

: after call to this function you need to initialize lcd display.

Definition at line 111 of file ssd1306_spi_usi.c.

ssd1306_uartInit_Builtin()

void ssd1306_uartInit_Builtin

(

uint32_t

baud

)

Initializes built-in implementation of uart functions, based on USART hw module. If you do not know uart parameters, try ssd1306_uartInit_Builtin(0).

Parameters

baud	uart baud rate

Note

: after call to this function you need to initialize lcd display.

Definition at line 63 of file ssd1306_uart_builtin.c.

Variable Documentation

s_ssd1306_cs

int8_t s_ssd1306_cs

chip enable pin to controll lcd display over spi

Definition at line 33 of file ssd1306_spi.c.

s_ssd1306_dc

int8_t s_ssd1306_dc

data/command control pin for spi interface of lcd display

Definition at line 34 of file ssd1306_spi.c.

s_ssd1306_spi_clock

uint32_t s_ssd1306_spi_clock

maximum SPI clock, supported by OLED display

Definition at line 35 of file ssd1306_spi.c.

ssd1306_intf

ssd1306_interface_t ssd1306_intf

Holds pointers to functions of currently initialized interface.

Definition at line 31 of file ssd1306_interface.c.