int main(void)
{
unsigned char write_data=0x75, recv_data;
int testn=0;
USART_init();
print_UART(" This is the test for TWI ");
_delay_ms(1000);
PORTD |= 0x80; ///turn led on
_delay_ms(100);
TWI_init_master();
sei();
print_UART(" Sending Start condition ");
TWI_start();
print_UART(" address= %x ", ((address<<1)|write));
TWI_write_address((address<<1)|write);
print_UART(" writing register = %x ", write_data);
TWI_write_byte(write_data); //write register
print_UART(" Repeat Start ");
TWI_start(); //repeated start
print_UART(" address read= %x ", ((address<<1)|read));
TWI_write_address((address<<1)|read);
print_UART(" read Data ");
recv_data=TWI_read_byte(1); ///read byte and nack
TWI_stop();
print_UART(" This is the value of the register= %x ", recv_data);
PORTD &= 0x7F;
return 0;
}
int main(void)
{
_delay_ms(2000);
DDRB=0xff;
TWI_init_master(); // Function to initialize TWI
while(1)
{
if(write_data==0x00)
write_data=1;
TWI_start(); // Function to send start condition
TWI_write_address(address+write); // Function to write address and data direction bit(write) on SDA
TWI_write_data(255); // Function to write data in slave
TWI_stop(); // Function to send stop condition
_delay_ms(100); // Delay of 10 mili second
PORTB=0xff;
TWI_start();
TWI_read_address(address+read); // Function to write address and data direction bit(read) on SDA
TWI_read_data(); // Function to read data from slave
TWI_stop();
_delay_ms(2000);
}
}
void TWI_read_buf(uint8_t SLA, uint8_t adr, uint8_t len, uint8_t *buf) {
TWI_start();
TWI_write(SLA);
TWI_write(adr);
TWI_start();
TWI_write(SLA + 1);
while (len--) *buf++ = TWI_read( len ? ACK : NACK );
TWI_stop();
}
void sfp_read_vendor_name(uint8_t *buf) {
uint8_t len=15;
TWI_start();
TWI_write(0xa0);
TWI_write(0x14);
TWI_start();
TWI_write(0xa1);
while (len--) *buf++ = TWI_read( len ? ACK : NACK );
TWI_stop();
}
void sfp_read_to_buf(uint8_t SLA, uint8_t len, uint8_t *buf) {
TWI_start();
TWI_write(SLA);
TWI_write(0xa0);
TWI_start();
TWI_write(SLA + 1);
while (len--) *buf++ = TWI_read( len ? ACK : NACK );
TWI_stop();
}
uint8_t TWI_read_int(uint8_t SLA) {
uint8_t data;
TWI_start();
TWI_write(SLA);
TWI_start();
TWI_write(SLA + 1);
data = TWI_read(NACK);
TWI_stop();
return data;
}
void EI2C_read_buf(uint8_t device, uint16_t subAddr, uint16_t len, uint8_t *buf) {
while (len--) {
TWI_start();
TWI_write(device | ((subAddr>>8)<<1) );
TWI_write(subAddr);
TWI_start();
TWI_write(device + 1);
*buf++ = TWI_read( NACK );
TWI_stop();
subAddr++;
}
}
void TWI_ScrollFrame(void)
{
uint8_t segindex=0,i,j;
uint8_t str_Ptr[8];
uint8_t activeStatus = 1;
while((segindex<8) && (NewMsgReceived==0))
{
activeStatus = 1;
NumberOfSegments = 1;
for(i=0; (activeStatus) && (NewMsgReceived==0);i++)
{
for(j=0;j<MaxColPerSegment;j++)
{
str_Ptr[j] = FrameBuffer[(i*8)+j+segindex];
}
if(i==0)
{
for(j=0;j<MaxColPerSegment;j++)
{
pattern[j] = str_Ptr[j];
}
}
else
{
activeStatus = TWI_start(); // Function to send start condition
if(activeStatus)
{
activeStatus = TWI_write_address(i*2+0x30); // Function to write address and data direction bit(write) on SDA
if(activeStatus)
{
NumberOfSegments++;
for(j=0;j<8;j++)
{
TWI_write_data(str_Ptr[j]); // Function to write data in slave
}
}
}
TWI_stop(); // Function to send stop condition
}
}
for(i=NumberOfSegments;i<MAX_DEVICES;i++)
DELAY_ms(SCROLL_DELAY_MS);
segindex++;
}
}
uint8_t TWI_write(uint8_t addr, uint8_t *s, uint8_t len){
// Save start local variable in case it is changed by an ISR
uint8_t start = twrite_start;
// Temporary end to handle circular buffer.
uint8_t end;
// Make sure end always is bigger than start.
if(start > twrite_end){
end = twrite_end + TWI_BUFFER_SIZE;
}
else end = twrite_end;
// Return false if the message doesn't fit in buffer.
if(len + 1> TWI_BUFFER_SIZE - 1 -(end - start)){
// TODO: signal buffer error.
return 0;
}
twrite_buff[twrite_end] = addr;
twrite_end = TWIca(twrite_end+1);
// Copy message to buffer.
for(int i = 0; i < len; ++i){
twrite_buff[twrite_end] = s[i];
twrite_end = TWIca(twrite_end+1);
}
TWI_start();
return 1;
}
void TWI_write_int( uint8_t SLA, uint8_t data) {
TWI_start();
TWI_write(SLA);
TWI_write(data);
TWI_stop();
}
void DisplayString(char *ptr_msgPointer)
{
int i,j;
uint8_t activeStatus = 1;
NumberOfSegments = 1;
BuildFrame(ptr_msgPointer);
for(i=0;activeStatus;i++)
{
if(i==0)
{
for(j=0;j<8;j++)
pattern[j] = FrameBuffer[j];
}
else
{
TWI_start(); // Function to send start condition
activeStatus = TWI_write_address(i*2+0x30); // Function to write address and data direction bit(write) on SDA
if(activeStatus)
{
NumberOfSegments++;
for(j=0;j<8;j++)
{
TWI_write_data(FrameBuffer[i*8+j]); // Function to write data in slave
// UART_TxChar(' ');
// UART_TxHexNumber(i,2); // Function to write data in slave
}
}
TWI_stop(); // Function to send stop condition
}
}
}
void TWI_write_buf( uint8_t SLA, uint8_t adr, uint8_t len, uint8_t *buf) {
TWI_start();
TWI_write(SLA);
TWI_write(adr);
while (len--) TWI_write(*buf++);
TWI_stop();
}
// funkcja do odczytu z EXPANDERA PCF8574 *********************
uint8_t PCF8574_read( uint8_t SLA ) {
uint8_t res=0;
TWI_start();
TWI_write(SLA + 1);
res = TWI_read( NACK );
TWI_stop();
return res;
}
void TWI_wait(char slave)
{
//send slave address until a slave ACKs it. Good for checking if the EEPROM
//has finished a write operation. Use carefully! If the wrong slave address
//is being waited for, this function will end in an infinite loop.
do {
TWI_start();
} while(TWI_write_data(slave) != 0x18);
TWI_stop();
}
/////////////////Functions/////////////////////////////////
void TWI_init_master(void) // Function to initialize master
{
TWBR=3; // Bit rate
TWSR=(0<<TWPS1)|(0<<TWPS0); // Setting prescalar bits
PORTD|=(1<<0)|(1<<1);
// SCL freq= F_CPU/(16+2(TWBR).4^TWPS)
TCCR2=0b00001011;
TIMSK|=1<<OCIE2;
OCR2=200;
TWI_start();
TWI_write_address(0xD2);
TWI_write_data(0x20);
TWI_write_data(0b11101111);
TWI_stop();
TWI_start();
TWI_write_address(0xD2);
TWI_write_data(0x23);
TWI_write_data(0b00010000);
TWI_stop();
}
void MPU_write_adress(unsigned char mpuAdress, unsigned char registerAdress, unsigned char value){
TWI_start();
TWI_check_ack(mpuAdress);
TWI_write_data(registerAdress);
TWI_write_data(value);
TWI_stop();
}
signed short int getdata(unsigned char add)
{
signed short int DATA;
TWI_start();
TWI_write_address(0xD2);
TWI_write_data(add);
TWI_repeated_start();
TWI_read_address(0xD3);
DATA=TWI_read_data();
TWI_stop();
return DATA;
}
void MPU_read_adress(unsigned char mpuAdress, unsigned char registerAdress, unsigned char* variable){
TWI_start();
TWI_check_ack(mpuAdress);
TWI_write_data(registerAdress);
TWI_repeated_start();
TWI_read_address(mpuAdress|0x01);
*variable = TWI_read_data();
TWI_stop();
}
char EE_read_byte(const int address)
{
char dummy;
//we need this for the first if()
dummy = TWI_start();
//as in EE_write_byte, first send the page address and the word address
if((dummy != 0x08) && (dummy != 0x10))
return TWSR;
if(TWI_write_data(EE_ADDR|((address>>7) & 0x000E)) != 0x18)
return TWSR;
if(TWI_write_data((char)(address)) != 0x28)
return TWSR;
//send a repeated start for entering master receiver mode
if(TWI_start() != 0x10)
return TWSR;
//send slave address, now with the read bit set
if(TWI_write_data((EE_ADDR|1)|((address>>7) & 0x000E)) != 0x40)
return TWSR;
//now get the data from the EEPROM, don't return ACK
if(TWI_read_data(0) != 0x58)
return TWSR;
//if everything was OK, return zero
return 0;
}
void MPU_self_test(unsigned char mpuAdress){
char buf[17]=" ";
TWI_start();
TWI_check_ack(mpuAdress);
TWI_write_data(0x75);
TWI_repeated_start();
TWI_read_address(mpuAdress|0x01);
char response = TWI_read_data();
sprintf(buf,"Response: %x",response);
LCD_WriteText(buf);
TWI_stop();
}
char EE_write_byte(const int address, const char data)
{
char dummy;
//we need this for the first if()
dummy = TWI_start();
//if the start was successful, continue, otherwise return 1
if((dummy != 0x08) && (dummy != 0x10))
return TWSR;
//now send the EEPROM slave address together with the address bits 8..10 for page select
//address format:
//|bit7 |bit6 |bit5 |bit4 |bit3 |bit2 |bit1 |bit0 |
//| EE_ADDR | page select | R/W |
if(TWI_write_data(EE_ADDR|((address>>7) & 0x000E)) != 0x18)
return TWSR;
//now send the word address byte
if(TWI_write_data((char)(address)) != 0x28)
return TWSR;
//now send the data byte
if(TWI_write_data(data) != 0x28)
return TWSR;
//if everything was OK, return zero.
return 0;
}