/*-----------------------------------------------------------------------------
* I2C_Recovery: Recovery procedure for I2C lines when irregular
* communication interrupt occures.
*
* Return: 0 on success, nonzero on error
*----------------------------------------------------------------------------*/
uint32_t I2C_Recovery (uint32_t err) {
uint32_t i;
#if 1
GPIOB->AFR[1] &= ~0x000000FF; /* Set SDA and SCL as GPIO */
I2C1->CR1 |= I2C_CR1_SWRST; /* Put I2C peripheral in reset mode */
io_dir (IO_SDA | IO_SCL, IO_OUT); /* SDA and SCL pins are outputs */
io_pin (IO_SDA | IO_SCL, IO_HI); /* Pull both lines high */
Wait();
io_pin (IO_SCL, IO_LOW); /* Generate start ccondition */
io_pin (IO_SDA, IO_HI); /* Pull SDA high */
for (i = 0; i < 9; i++) {
if (io_state (IO_SDA) == IO_HI) break; /* Break if SDA released by slave */
io_pin (IO_SCL, IO_HI); /* Clock high */
Wait();
io_pin (IO_SCL, IO_LOW); /* Clock low */
Wait();
}
/* Send stop */
io_pin (IO_SDA, IO_LOW); /* Pull SDA low */
io_pin (IO_SCL, IO_HI); /* Pull SCL high */
Wait();
io_pin (IO_SDA, IO_HI); /* Pull SDA high == stop condition */
I2C1->CR1 &= ~I2C_CR1_SWRST; /* Dereset I2C peripheral */
return (I2C_Init()); /* Reinit I2C peripheral */
#else
return (1);
#endif
}
void gpio_input(unsigned char idx) //14may15 experiment
{
uint32_t ioFlags;
unsigned char ioPin;
ioPin = io_pin(idx);
ioport_set_pin_dir(ioPin, IOPORT_DIR_INPUT);
}
void release_the_bus(unsigned char idx)
{
unsigned char ioPin;
int32_t ioFlags;
ioPin = io_pin(idx);
ioport_set_pin_dir(ioPin, IOPORT_DIR_INPUT);
}
void drive_DQ_low(unsigned char idx)
{
unsigned char ioPin;
int32_t ioFlags;
ioPin = io_pin(idx);
ioport_set_pin_dir(ioPin, IOPORT_DIR_OUTPUT);
ioport_set_pin_level(ioPin, IOPORT_PIN_LEVEL_LOW);
}
void drive_DQ_low_and_release_the_bus(unsigned char idx)
{
unsigned char ioPin;
int32_t ioFlagsOutput, ioFlagsInput;
ioPin = io_pin(idx);
ioport_set_pin_dir(ioPin, IOPORT_DIR_OUTPUT);
ioport_set_pin_level(ioPin, IOPORT_PIN_LEVEL_LOW);
udelay(A); //tW1L 5-15us
ioport_set_pin_dir(ioPin, IOPORT_DIR_INPUT);
}
unsigned char sample_line(unsigned char idx)
{
//14may15 experiment uint32_t ioFlags;
unsigned char retVal, ioPin;
ioPin = io_pin(idx);
//14may15 experiment ioFlags = (GPIO_DIR_INPUT);
//14may15 experiment gpio_configure_pin(ioPin, ioFlags);
retVal = ioport_get_pin_level(ioPin);
//14may15 experiment ioFlags = (GPIO_DIR_OUTPUT);
//14may15 experiment gpio_configure_pin(ioPin, ioFlags);
return retVal;
}
