Tool/software: Code Composer Studio
Hello, guys. I'm using TIVA TM4C123GXL for a while and tried now to use I2C module. First, tried to make it write and read a 24C04 memory, exactly the same way I did thousand times with PIC. But it didn't worked: all I read is 0xFF even after writing the same adress.
I won a SD1306 display and tried too, but again, it didn't work. So, am I missing something about TI I2C module? The display is connected to board, supplied with 3V3 from board but when I turn on the circuit, nothing happens on display and my green LED lights up (see at the bottom of the code), meaning it has executed all the instructions. Here is my code:
#include <stdint.h>
#include <stdbool.h>
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "driverlib/debug.h"
#include "driverlib/gpio.h"
#include "driverlib/rom.h"
#include "driverlib/rom_map.h"
#include "driverlib/pin_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/i2c.h"
//*****************************************************************************
// The error routine that is called if the driver library encounters an error.
//*****************************************************************************
#ifdef DEBUG
void
__error__(char *pcFilename, uint32_t ui32Line)
{
while(1);
}
#endif
//*****************************************************************************
// Definicoes das interfaces da placa Tiva
//*****************************************************************************
#define RED_LED GPIO_PIN_1 //PF1
#define BLUE_LED GPIO_PIN_2 //PF2
#define GREEN_LED GPIO_PIN_3 //PF3
#define SW1 GPIO_PIN_4 //PF4
#define SW2 GPIO_PIN_0 //PF0
//*****************************************************************************
// Display definitions
//*****************************************************************************
#define SSD1306_LCDWIDTH 128
#define SSD1306_LCDHEIGHT 64
#define SSD1306_SETCONTRAST 0x81
#define SSD1306_DISPLAYALLON_RESUME 0xA4
#define SSD1306_DISPLAYALLON 0xA5
#define SSD1306_NORMALDISPLAY 0xA6
#define SSD1306_INVERTDISPLAY 0xA7
#define SSD1306_DISPLAYOFF 0xAE
#define SSD1306_DISPLAYON 0xAF
#define SSD1306_SETDISPLAYOFFSET 0xD3
#define SSD1306_SETCOMPINS 0xDA
#define SSD1306_SETVCOMDETECT 0xDB
#define SSD1306_SETDISPLAYCLOCKDIV 0xD5
#define SSD1306_SETPRECHARGE 0xD9
#define SSD1306_SETMULTIPLEX 0xA8
#define SSD1306_SETLOWCOLUMN 0x00
#define SSD1306_SETHIGHCOLUMN 0x10
#define SSD1306_SETSTARTLINE 0x40
#define SSD1306_MEMORYMODE 0x20
#define SSD1306_COLUMNADDR 0x21
#define SSD1306_PAGEADDR 0x22
#define SSD1306_COMSCANINC 0xC0
#define SSD1306_COMSCANDEC 0xC8
#define SSD1306_SEGREMAP 0xA0
#define SSD1306_CHARGEPUMP 0x8D
#define SSD1306_EXTERNALVCC 0x1
#define SSD1306_SWITCHCAPVCC 0x2
void delay_ms (uint16_t atraso)
{
if (atraso != 0)
SysCtlDelay(atraso*(SysCtlClockGet()/(3*1000))); // Atraso de 1ms
}
void I2C0_Init(void)
{
//
// Enable Peripheral Clocks
//
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_I2C0);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
//
// Enable pin PB2 for I2C0 I2C0SCL
//
MAP_GPIOPinConfigure(GPIO_PB2_I2C0SCL);
MAP_GPIOPinTypeI2CSCL(GPIO_PORTB_BASE, GPIO_PIN_2);
//
// Enable pin PB3 for I2C0 I2C0SDA
//
MAP_GPIOPinConfigure(GPIO_PB3_I2C0SDA);
MAP_GPIOPinTypeI2C(GPIO_PORTB_BASE, GPIO_PIN_3);
MAP_I2CMasterInitExpClk(I2C0_BASE, SysCtlClockGet(), true);
}
void SSD1306_command(uint8_t c)
{
uint8_t control = 0x80; // some use 0X00 other examples use 0X80. I tried both
MAP_I2CMasterSlaveAddrSet(I2C0_BASE, 0x78, false);
MAP_I2CMasterDataPut(I2C0_BASE, control);
MAP_I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_BURST_SEND_START);
while(MAP_I2CMasterBusy(I2C0_BASE));
MAP_I2CMasterDataPut(I2C0_BASE, c);
MAP_I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_BURST_SEND_FINISH);
while(MAP_I2CMasterBusy(I2C0_BASE));
}
// init according to SSD1306 data sheet and many places on the web
void Initialize_SSD1306()
{
// Init sequence for 128x64 OLED module
SSD1306_command(SSD1306_DISPLAYOFF); // 0xAE
SSD1306_command(SSD1306_SETDISPLAYCLOCKDIV); // 0xD5
SSD1306_command(0x80); // the suggested ratio 0x80
SSD1306_command(SSD1306_SETMULTIPLEX); // 0xA8
SSD1306_command(0x3F);
SSD1306_command(SSD1306_SETDISPLAYOFFSET); // 0xD3
SSD1306_command(0x0); // no offset
SSD1306_command(SSD1306_SETSTARTLINE);// | 0x0); // line #0
SSD1306_command(SSD1306_CHARGEPUMP); // 0x8D
SSD1306_command(0x14); // using internal VCC
SSD1306_command(SSD1306_MEMORYMODE); // 0x20
SSD1306_command(0x00); // 0x00 horizontal addressing
SSD1306_command(SSD1306_SEGREMAP | 0x1); // rotate screen 180
SSD1306_command(SSD1306_COMSCANDEC); // rotate screen 180
SSD1306_command(SSD1306_SETCOMPINS); // 0xDA
SSD1306_command(0x12);
SSD1306_command(SSD1306_SETCONTRAST); // 0x81
SSD1306_command(0xCF);
SSD1306_command(SSD1306_SETPRECHARGE); // 0xd9
SSD1306_command(0xF1);
SSD1306_command(SSD1306_SETVCOMDETECT); // 0xDB
SSD1306_command(0x40);
SSD1306_command(SSD1306_DISPLAYALLON_RESUME); // 0xA4
SSD1306_command(SSD1306_NORMALDISPLAY); // 0xA6
SSD1306_command(SSD1306_DISPLAYON); //switch on OLED
}
//*****************************************************************************
// Main
//*****************************************************************************
int main(void)
{
MAP_SysCtlClockSet(SYSCTL_SYSDIV_4|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
while(!MAP_SysCtlPeripheralReady(SYSCTL_PERIPH_GPIOF));
MAP_GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, RED_LED|BLUE_LED|GREEN_LED);
I2C0_Init();
Initialize_SSD1306();
SSD1306_command(SSD1306_DISPLAYALLON);
GPIOPinWrite(GPIO_PORTF_BASE, GREEN_LED, GREEN_LED);
ROM_SysCtlSleep();
}
I need some help. I can't have such microcontroller and not be able to understand how to use it's I2C module.
