static uint8_t getByte(const I2C_ABSTRACT_BUS* bus, boolean isLastByte){
const I2C_SOFTWARE_BUS* i2c = (const I2C_SOFTWARE_BUS*)bus;
int8_t i;
uint8_t b = 0;
sda_high(i2c);
for(i=7; i>=0; i--){
b <<= 1;
scl_high(i2c);
halfDelay();
if(pin_is_high(i2c->sda)){
b |= 1;
}
scl_low(i2c);
halfDelay();
}
// Put the ACK
if(isLastByte){
sda_high(i2c);
}else{
sda_low(i2c);
}
scl_high(i2c);
halfDelay(i2c);
scl_low(i2c);
sda_high(i2c);
return b; // return received byte
}
static void init(I2C_ABSTRACT_BUS* bus){
const I2C_SOFTWARE_BUS* i2c = (I2C_SOFTWARE_BUS*)bus;
// Make both pins high
sda_high(i2c);
scl_high(i2c);
}
//------------------------------------------------------------------------
static unsigned int i2c_write_byte ( unsigned int b )
{
unsigned int ra;
for(ra=0x80;ra;ra>>=1)
{
i2c_delay();
if(ra&b) sda_high();
else sda_low();
i2c_delay();
scl_high();
i2c_delay();
scl_low();
i2c_delay();
sda_low();
i2c_delay();
}
i2c_delay();
sda_input();
i2c_delay();
scl_high();
i2c_delay();
ra=sda_read();
i2c_delay();
scl_low();
i2c_delay();
sda_output();
i2c_delay();
return(ra);
}
// Send the start and address
// return TRUE if acknowledged
static boolean start(const I2C_ABSTRACT_BUS* bus, uint8_t addr, boolean writeMode){
boolean rtn = FALSE;
const I2C_SOFTWARE_BUS* i2c = (const I2C_SOFTWARE_BUS*)bus;
if(i2c){
sda_high(i2c);
halfDelay();
scl_high(i2c);
halfDelay();
sda_low(i2c);
halfDelay();
scl_low(i2c);
halfDelay();
// Send the device addr and direction
// uint8_t addr = device->addr & 0xfe;
if(writeMode==FALSE){
addr |= 1;
}else{
addr &= 0xfe;
}
rtn = putByte(bus, addr);
}
return rtn;
}
// Return true if the slave acknowledges
static boolean getAck(const I2C_SOFTWARE_BUS* i2c){
sda_high(i2c); // allow slave to drive sda
scl_high(i2c);
halfDelay();
boolean rtn = pin_is_low(i2c->sda);
scl_low(i2c);
return rtn;
}
// Send the stop
static void stop(const I2C_ABSTRACT_BUS* bus){
const I2C_SOFTWARE_BUS* i2c = (const I2C_SOFTWARE_BUS*)bus;
sda_low(i2c);
halfDelay();
scl_high(i2c);
halfDelay();
sda_high(i2c);
halfDelay();
}
//------------------------------------------------------------------------
static void i2c_stop ( void )
{
i2c_delay();
scl_high();
i2c_delay();
sda_high();
i2c_delay();
i2c_delay();
}
// Put a byte across the wire
// Return true if the slave acknowledges
static boolean putByte(const I2C_ABSTRACT_BUS* bus, uint8_t b){
const I2C_SOFTWARE_BUS* i2c = (const I2C_SOFTWARE_BUS*)bus;
int8_t i;
for(i=7; i>=0; i--){
if( b & 0x80 ){
sda_high(i2c);
}else{
sda_low(i2c);
}
scl_high(i2c);
b <<= 1;
scl_low(i2c);
}
return getAck(i2c); // return ACK value
}
int main(void) {
int test;
unsigned char byte;
// PCF_ADRESS = 0; // Adresse des PCF'S
printf("*** i²c-LCD Test (c) Ingo Gerlach 10/2000 *** \n");
COM = 0; // Vorbelegung Ser - Port, 0 Automatisch suchen
set_port_delay(15); // Portdelay 0-255
test = init_iic(COM); // Init ii2c
printf("Suche i2c-Interface...");
if (test)
{
printf(" gefunden an Port 0x%03xh! \n",test);
} else {
printf("Interface nicht gefunden.\n");
exit (0);
}
/*
set_strobe(1); // Für den Seriellen Port nur dummy
io_disable(0);
*/
sda_high();
scl_high();
printf("read_sda %d \n",read_sda());
printf("read_scl %d \n",read_scl());
iic_start();
byte =getchar();
iic_stop();
sda_low();
scl_low();
printf("read_sda %d \n",read_sda());
printf("read_scl %d \n",read_scl());
lcd_backlight(0);
byte = getchar();
printf("deinit %d\n",deinit_iic());
return 0;
}
// Send the start and address
// return TRUE if acknowledged
static boolean start(const I2C_DEVICE* device, boolean writeMode){
boolean rtn = FALSE;
const I2C_SOFTWARE_BUS* i2c = (const I2C_SOFTWARE_BUS*)(device->bus);
if(i2c){
sda_high(i2c);
halfDelay();
scl_high(i2c);
halfDelay();
sda_low(i2c);
halfDelay();
scl_low(i2c);
halfDelay();
// Send the device addr and direction
uint8_t addr = device->addr & 0xfe;
if(writeMode==FALSE){
addr |= 1;
}
rtn = putByte(device->bus, addr);
}
return rtn;
}
