Added AVR hardware i2c support and example project
This commit is contained in:
QB4-dev
parent
915678e10d
commit
7122907f6d
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@ -14,6 +14,7 @@ CFLAGS = \
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-fdata-sections \
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-I$(U8G2_SRC)/ \
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-I../lib/ \
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-DAVR_USE_HW_SPI \
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-DSCK_DDR=DDRB \
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-DSCK_BIT=1 \
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-DMOSI_DDR=DDRB \
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@ -41,4 +42,4 @@ clean:
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# Example for Teensy 2.0++
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upload: main.hex
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$(TEENSY_LOADER) -mmcu=$(MCU) -w -v main.hex
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$(TEENSY_LOADER) -mmcu=$(MCU) -w -v main.hex
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@ -0,0 +1,42 @@
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CC = avr-gcc
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OBJCPY = avr-objcopy
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SIZE = avr-size
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MCU = atmega328p
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F_CPU = 16000000
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U8G2_SRC = ../../../../csrc
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CFLAGS = \
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-mmcu=$(MCU) \
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-DF_CPU=$(F_CPU)UL \
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-Os \
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-std=gnu99 \
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-Werror \
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-ffunction-sections \
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-fdata-sections \
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-I$(U8G2_SRC)/ \
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-I../lib/ \
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-DAVR_USE_HW_I2C
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LDFLAGS = \
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-Wl,--gc-sections \
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-mmcu=$(MCU)
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AVRDUDE=avrdude
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PORT=/dev/serial/by-id/usb-FTDI_FT232R_USB_UART_A4008fhY-if00-port0
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SRC = $(shell ls $(U8G2_SRC)/*.c) $(shell ls ../lib/*.c) $(shell ls ../lib/avr-hw-i2c/*.c) $(shell ls ./*.c)
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OBJ = $(SRC:.c=.o)
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main.hex: main.elf
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$(OBJCPY) -O ihex -R .eeprom -R .fuse -R .lock -R .signature main.elf main.hex
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main.elf: $(OBJ)
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$(CC) $(CFLAGS) $(LDFLAGS) $(OBJ) -o $@
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size: main.elf
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$(SIZE) --mcu=$(MCU) --format=avr main.elf
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clean:
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rm -f $(OBJ) main.elf main.hex
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# Example for Arduino Duemilanove
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upload: main.hex
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$(AVRDUDE) -p$(MCU) -carduino -P$(PORT) -b57600 -D -Uflash:w:main.hex:i
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Binary file not shown.
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After Width: | Height: | Size: 708 KiB |
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@ -0,0 +1,27 @@
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#include <avr/io.h>
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#include <util/delay.h>
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#include <u8g2.h>
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#include <u8x8_avr.h>
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#define SSD1306_ADDR 0x78
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u8g2_t u8g2;
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int main (void)
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{
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u8g2_Setup_ssd1306_i2c_128x32_univision_f(&u8g2, U8G2_R0, u8x8_byte_avr_hw_i2c, u8x8_avr_delay);
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u8g2_SetI2CAddress(&u8g2, SSD1306_ADDR);
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u8g2_InitDisplay(&u8g2);
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u8g2_SetPowerSave(&u8g2, 0);
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while(1){
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u8g2_ClearBuffer(&u8g2);
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u8g2_SetFont(&u8g2, u8g2_font_smart_patrol_nbp_tr);
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u8g2_SetFontRefHeightText(&u8g2);
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u8g2_SetFontPosTop(&u8g2);
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u8g2_DrawStr(&u8g2, 0, 0, "u8g2 AVR HW I2C");
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u8g2_SendBuffer(&u8g2);
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}
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}
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@ -14,6 +14,7 @@ CFLAGS = \
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-fdata-sections \
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-I$(U8G2_SRC)/ \
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-I../lib/ \
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-DAVR_USE_HW_SPI \
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-DSCK_DDR=DDRB \
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-DSCK_BIT=5 \
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-DMOSI_DDR=DDRB \
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@ -42,4 +43,4 @@ clean:
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# Example for Arduino Duemilanove
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upload: main.hex
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$(AVRDUDE) -p$(MCU) -carduino -P$(PORT) -b57600 -D -Uflash:w:main.hex:i
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$(AVRDUDE) -p$(MCU) -carduino -P$(PORT) -b57600 -D -Uflash:w:main.hex:i
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@ -0,0 +1,178 @@
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#ifndef _I2CMASTER_H
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#define _I2CMASTER_H 1
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/*************************************************************************
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* Title: C include file for the I2C master interface
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* (i2cmaster.S or twimaster.c)
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* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
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* File: $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $
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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Target: any AVR device
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* Usage: see Doxygen manual
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**************************************************************************/
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#ifdef DOXYGEN
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/**
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@defgroup pfleury_ic2master I2C Master library
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@code #include <i2cmaster.h> @endcode
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@brief I2C (TWI) Master Software Library
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Basic routines for communicating with I2C slave devices. This single master
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implementation is limited to one bus master on the I2C bus.
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This I2c library is implemented as a compact assembler software implementation of the I2C protocol
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which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c).
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Since the API for these two implementations is exactly the same, an application can be linked either against the
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software I2C implementation or the hardware I2C implementation.
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Use 4.7k pull-up resistor on the SDA and SCL pin.
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Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module
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i2cmaster.S to your target when using the software I2C implementation !
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Adjust the CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion.
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@note
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The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted
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to GNU assembler and AVR-GCC C call interface.
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Replaced the incorrect quarter period delays found in AVR300 with
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half period delays.
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@author Peter Fleury pfleury@gmx.ch http://jump.to/fleury
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@par API Usage Example
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The following code shows typical usage of this library, see example test_i2cmaster.c
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@code
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#include <i2cmaster.h>
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#define Dev24C02 0xA2 // device address of EEPROM 24C02, see datasheet
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int main(void)
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{
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unsigned char ret;
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i2c_init(); // initialize I2C library
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// write 0x75 to EEPROM address 5 (Byte Write)
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i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
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i2c_write(0x05); // write address = 5
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i2c_write(0x75); // write value 0x75 to EEPROM
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i2c_stop(); // set stop conditon = release bus
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// read previously written value back from EEPROM address 5
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i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode
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i2c_write(0x05); // write address = 5
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i2c_rep_start(Dev24C02+I2C_READ); // set device address and read mode
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ret = i2c_readNak(); // read one byte from EEPROM
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i2c_stop();
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for(;;);
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}
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@endcode
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*/
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#endif /* DOXYGEN */
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/**@{*/
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#if (__GNUC__ * 100 + __GNUC_MINOR__) < 304
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#error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !"
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#endif
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#include <avr/io.h>
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/** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */
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#define I2C_READ 1
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/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */
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#define I2C_WRITE 0
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/**
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@brief initialize the I2C master interace. Need to be called only once
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@param void
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@return none
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*/
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extern void i2c_init(void);
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/**
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@brief Terminates the data transfer and releases the I2C bus
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@param void
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@return none
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*/
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extern void i2c_stop(void);
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/**
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@brief Issues a start condition and sends address and transfer direction
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@param addr address and transfer direction of I2C device
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@retval 0 device accessible
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@retval 1 failed to access device
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*/
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extern unsigned char i2c_start(unsigned char addr);
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/**
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@brief Issues a repeated start condition and sends address and transfer direction
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@param addr address and transfer direction of I2C device
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@retval 0 device accessible
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@retval 1 failed to access device
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*/
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extern unsigned char i2c_rep_start(unsigned char addr);
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/**
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@brief Issues a start condition and sends address and transfer direction
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If device is busy, use ack polling to wait until device ready
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@param addr address and transfer direction of I2C device
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@return none
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*/
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extern void i2c_start_wait(unsigned char addr);
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/**
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@brief Send one byte to I2C device
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@param data byte to be transfered
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@retval 0 write successful
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@retval 1 write failed
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*/
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extern unsigned char i2c_write(unsigned char data);
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/**
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@brief read one byte from the I2C device, request more data from device
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@return byte read from I2C device
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*/
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extern unsigned char i2c_readAck(void);
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/**
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@brief read one byte from the I2C device, read is followed by a stop condition
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@return byte read from I2C device
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*/
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extern unsigned char i2c_readNak(void);
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/**
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@brief read one byte from the I2C device
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Implemented as a macro, which calls either i2c_readAck or i2c_readNak
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@param ack 1 send ack, request more data from device<br>
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0 send nak, read is followed by a stop condition
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@return byte read from I2C device
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*/
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extern unsigned char i2c_read(unsigned char ack);
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#define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak();
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/**@}*/
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#endif
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@ -0,0 +1,236 @@
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/*
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* modified version of I2C master library
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* added a timeout variable for non blocking i2c
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*/
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/*************************************************************************
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* Title: I2C master library using hardware TWI interface
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* Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury
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* File: $Id: twimaster.c,v 1.3 2005/07/02 11:14:21 Peter Exp $
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* Software: AVR-GCC 3.4.3 / avr-libc 1.2.3
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* Target: any AVR device with hardware TWI
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* Usage: API compatible with I2C Software Library i2cmaster.h
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**************************************************************************/
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#include <avr-hw-i2c/i2cmaster.h>
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#include <inttypes.h>
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#include <compat/twi.h>
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/* define CPU frequency in Mhz here if not defined in Makefile */
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#ifndef F_CPU
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#define F_CPU 4000000UL
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#endif
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/* I2C clock in Hz */
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#define SCL_CLOCK 100000L
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/* I2C timer max delay */
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#define I2C_TIMER_DELAY 0xFF
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/*************************************************************************
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Initialization of the I2C bus interface. Need to be called only once
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*************************************************************************/
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void i2c_init(void)
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{
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/* initialize TWI clock: 100 kHz clock, TWPS = 0 => prescaler = 1 */
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TWSR = 0; /* no prescaler */
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TWBR = ((F_CPU/SCL_CLOCK)-16)/2; /* must be > 10 for stable operation */
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}/* i2c_init */
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/*************************************************************************
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Issues a start condition and sends address and transfer direction.
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return 0 = device accessible, 1= failed to access device
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*************************************************************************/
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unsigned char i2c_start(unsigned char address)
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{
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uint32_t i2c_timer = 0;
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uint8_t twst;
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// send START condition
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TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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// wait until transmission completed
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i2c_timer = I2C_TIMER_DELAY;
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while(!(TWCR & (1<<TWINT)) && i2c_timer--);
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if(i2c_timer == 0)
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return 1;
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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if ( (twst != TW_START) && (twst != TW_REP_START)) return 1;
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// send device address
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TWDR = address;
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TWCR = (1<<TWINT) | (1<<TWEN);
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// wail until transmission completed and ACK/NACK has been received
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i2c_timer = I2C_TIMER_DELAY;
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while(!(TWCR & (1<<TWINT)) && i2c_timer--);
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if(i2c_timer == 0)
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return 1;
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1;
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return 0;
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}/* i2c_start */
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/*************************************************************************
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Issues a start condition and sends address and transfer direction.
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If device is busy, use ack polling to wait until device is ready
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Input: address and transfer direction of I2C device
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*************************************************************************/
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void i2c_start_wait(unsigned char address)
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{
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uint32_t i2c_timer = 0;
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uint8_t twst;
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while ( 1 )
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{
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// send START condition
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TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
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// wait until transmission completed
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i2c_timer = I2C_TIMER_DELAY;
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while(!(TWCR & (1<<TWINT)) && i2c_timer--);
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
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// send device address
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TWDR = address;
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TWCR = (1<<TWINT) | (1<<TWEN);
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// wail until transmission completed
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i2c_timer = I2C_TIMER_DELAY;
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while(!(TWCR & (1<<TWINT)) && i2c_timer--);
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// check value of TWI Status Register. Mask prescaler bits.
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twst = TW_STATUS & 0xF8;
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if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
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{
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/* device busy, send stop condition to terminate write operation */
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TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
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// wait until stop condition is executed and bus released
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i2c_timer = I2C_TIMER_DELAY;
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while((TWCR & (1<<TWSTO)) && i2c_timer--);
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continue;
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}
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//if( twst != TW_MT_SLA_ACK) return 1;
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break;
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}
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}/* i2c_start_wait */
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/*************************************************************************
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Issues a repeated start condition and sends address and transfer direction
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Input: address and transfer direction of I2C device
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Return: 0 device accessible
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1 failed to access device
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*************************************************************************/
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unsigned char i2c_rep_start(unsigned char address)
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{
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return i2c_start( address );
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}/* i2c_rep_start */
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/*************************************************************************
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Terminates the data transfer and releases the I2C bus
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*************************************************************************/
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void i2c_stop(void)
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{
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uint32_t i2c_timer = 0;
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/* send stop condition */
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TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
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// wait until stop condition is executed and bus released
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i2c_timer = I2C_TIMER_DELAY;
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while((TWCR & (1<<TWSTO)) && i2c_timer--);
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}/* i2c_stop */
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/*************************************************************************
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Send one byte to I2C device
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Input: byte to be transfered
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Return: 0 write successful
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1 write failed
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*************************************************************************/
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unsigned char i2c_write( unsigned char data )
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{
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uint32_t i2c_timer = 0;
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uint8_t twst;
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// send data to the previously addressed device
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TWDR = data;
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TWCR = (1<<TWINT) | (1<<TWEN);
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// wait until transmission completed
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i2c_timer = I2C_TIMER_DELAY;
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while(!(TWCR & (1<<TWINT)) && i2c_timer--);
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if(i2c_timer == 0)
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return 1;
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// check value of TWI Status Register. Mask prescaler bits
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twst = TW_STATUS & 0xF8;
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if( twst != TW_MT_DATA_ACK) return 1;
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return 0;
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}/* i2c_write */
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||||
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||||
/*************************************************************************
|
||||
Read one byte from the I2C device, request more data from device
|
||||
|
||||
Return: byte read from I2C device
|
||||
*************************************************************************/
|
||||
unsigned char i2c_readAck(void)
|
||||
{
|
||||
uint32_t i2c_timer = 0;
|
||||
|
||||
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
|
||||
i2c_timer = I2C_TIMER_DELAY;
|
||||
while(!(TWCR & (1<<TWINT)) && i2c_timer--);
|
||||
if(i2c_timer == 0)
|
||||
return 0;
|
||||
|
||||
return TWDR;
|
||||
|
||||
}/* i2c_readAck */
|
||||
|
||||
|
||||
/*************************************************************************
|
||||
Read one byte from the I2C device, read is followed by a stop condition
|
||||
|
||||
Return: byte read from I2C device
|
||||
*************************************************************************/
|
||||
unsigned char i2c_readNak(void)
|
||||
{
|
||||
uint32_t i2c_timer = 0;
|
||||
|
||||
TWCR = (1<<TWINT) | (1<<TWEN);
|
||||
i2c_timer = I2C_TIMER_DELAY;
|
||||
while(!(TWCR & (1<<TWINT)) && i2c_timer--);
|
||||
if(i2c_timer == 0)
|
||||
return 0;
|
||||
|
||||
return TWDR;
|
||||
|
||||
}/* i2c_readNak */
|
||||
|
|
@ -1,7 +1,11 @@
|
|||
#include "u8x8_avr.h"
|
||||
#include <util/delay.h>
|
||||
#include "u8x8_avr.h"
|
||||
|
||||
#define P_CPU_NS (1000000000UL / F_CPU)
|
||||
#ifdef AVR_USE_HW_I2C
|
||||
#include <avr-hw-i2c/i2cmaster.h>
|
||||
#endif
|
||||
|
||||
#ifdef AVR_USE_HW_SPI
|
||||
|
||||
#ifndef SCK_DDR
|
||||
#error "SCK_DDR must be defined externally, eg: -DSCK_DDR=DDRB, for atmega328p."
|
||||
|
|
@ -19,6 +23,12 @@
|
|||
#error "MOSI_BIT must be defined externally, eg: -DMOSI_BIT=3, for atmega328p."
|
||||
#endif
|
||||
|
||||
#endif
|
||||
|
||||
#define P_CPU_NS (1000000000UL / F_CPU)
|
||||
|
||||
|
||||
#ifdef AVR_USE_HW_SPI
|
||||
uint8_t u8x8_byte_avr_hw_spi (u8x8_t * u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) {
|
||||
uint8_t *data;
|
||||
|
||||
|
|
@ -98,42 +108,70 @@ uint8_t u8x8_byte_avr_hw_spi (u8x8_t * u8x8, uint8_t msg, uint8_t arg_int, void
|
|||
|
||||
return 1;
|
||||
}
|
||||
#endif
|
||||
|
||||
#ifdef AVR_USE_HW_I2C
|
||||
uint8_t u8x8_byte_avr_hw_i2c(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr)
|
||||
{
|
||||
uint8_t *data;
|
||||
switch(msg){
|
||||
case U8X8_MSG_BYTE_SEND:
|
||||
data = (uint8_t *)arg_ptr;
|
||||
while( arg_int-- )
|
||||
i2c_write(*data++);
|
||||
break;
|
||||
case U8X8_MSG_BYTE_INIT:
|
||||
i2c_init();
|
||||
break;
|
||||
case U8X8_MSG_BYTE_SET_DC:
|
||||
/* ignored for i2c */
|
||||
break;
|
||||
case U8X8_MSG_BYTE_START_TRANSFER:
|
||||
i2c_start_wait(u8x8_GetI2CAddress(u8x8)+I2C_WRITE);
|
||||
break;
|
||||
case U8X8_MSG_BYTE_END_TRANSFER:
|
||||
i2c_stop();
|
||||
break;
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
#endif
|
||||
|
||||
uint8_t u8x8_avr_delay (u8x8_t * u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr) {
|
||||
uint8_t cycles;
|
||||
uint8_t cycles;
|
||||
|
||||
switch (msg) {
|
||||
case U8X8_MSG_DELAY_NANO: // delay arg_int * 1 nano second
|
||||
// At 20Mhz, each cycle is 50ns, the call itself is slower.
|
||||
break;
|
||||
case U8X8_MSG_DELAY_100NANO: // delay arg_int * 100 nano seconds
|
||||
// Approximate best case values...
|
||||
#define CALL_CYCLES 26UL
|
||||
#define CALC_CYCLES 4UL
|
||||
#define RETURN_CYCLES 4UL
|
||||
#define CYCLES_PER_LOOP 4UL
|
||||
switch(msg) {
|
||||
case U8X8_MSG_DELAY_NANO: // delay arg_int * 1 nano second
|
||||
// At 20Mhz, each cycle is 50ns, the call itself is slower.
|
||||
break;
|
||||
case U8X8_MSG_DELAY_100NANO: // delay arg_int * 100 nano seconds
|
||||
// Approximate best case values...
|
||||
#define CALL_CYCLES 26UL
|
||||
#define CALC_CYCLES 4UL
|
||||
#define RETURN_CYCLES 4UL
|
||||
#define CYCLES_PER_LOOP 4UL
|
||||
|
||||
cycles = (100UL * arg_int) / (P_CPU_NS * CYCLES_PER_LOOP);
|
||||
cycles = (100UL * arg_int) / (P_CPU_NS * CYCLES_PER_LOOP);
|
||||
|
||||
if (cycles > CALL_CYCLES + RETURN_CYCLES + CALC_CYCLES)
|
||||
break;
|
||||
if (cycles > CALL_CYCLES + RETURN_CYCLES + CALC_CYCLES)
|
||||
break;
|
||||
|
||||
__asm__ __volatile__ (
|
||||
"1: sbiw %0,1" "\n\t" // 2 cycles
|
||||
"brne 1b":"=w" (cycles):"0" (cycles) // 2 cycles
|
||||
);
|
||||
break;
|
||||
case U8X8_MSG_DELAY_10MICRO: // delay arg_int * 10 micro seconds
|
||||
for (int i = 0; i < arg_int; i++)
|
||||
_delay_us(10);
|
||||
break;
|
||||
case U8X8_MSG_DELAY_MILLI: // delay arg_int * 1 milli second
|
||||
for (int i = 0; i < arg_int; i++)
|
||||
_delay_ms(1);
|
||||
break;
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
__asm__ __volatile__ (
|
||||
"1: sbiw %0,1" "\n\t" // 2 cycles
|
||||
"brne 1b":"=w" (cycles):"0" (cycles) // 2 cycles
|
||||
);
|
||||
break;
|
||||
case U8X8_MSG_DELAY_10MICRO: // delay arg_int * 10 micro seconds
|
||||
while( arg_int-- ) _delay_us(10);
|
||||
break;
|
||||
case U8X8_MSG_DELAY_MILLI: // delay arg_int * 1 milli second
|
||||
while( arg_int-- ) _delay_ms(1);
|
||||
break;
|
||||
default:
|
||||
return 0;
|
||||
}
|
||||
|
||||
return 1;
|
||||
return 1;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1,5 +1,11 @@
|
|||
#ifndef U8X8_AVR_H_
|
||||
#define U8X8_AVR_H_
|
||||
|
||||
#include <u8g2.h>
|
||||
#include <stdint.h>
|
||||
|
||||
uint8_t u8x8_byte_avr_hw_spi(u8x8_t * u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
|
||||
uint8_t u8x8_avr_delay(u8x8_t * u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
|
||||
uint8_t u8x8_byte_avr_hw_i2c(u8x8_t *u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
|
||||
uint8_t u8x8_avr_delay(u8x8_t * u8x8, uint8_t msg, uint8_t arg_int, void *arg_ptr);
|
||||
|
||||
#endif /* U8X8_AVR_H_ */
|
||||
|
|
|
|||
Loading…
Reference in New Issue