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#include "project.h"
#ifndef SLIM
#define GPIO_SCL GPIOB
#define GPIO_SDA GPIOB
#define SCL GPIO13
#define SDA GPIO14
#define I2C_BB_DELAY do { delay_us(1); } while (0)
int
i2c_bb (int scl, int sda)
{
if (scl)
gpio_set (GPIO_SCL, SCL);
else
gpio_clear (GPIO_SCL, SCL);
if (sda)
gpio_set (GPIO_SDA, SDA);
else
gpio_clear (GPIO_SDA, SDA);
return ! !(gpio_get (GPIO_SDA, SDA) & SDA);
}
void
i2c_bb_start (void)
{
i2c_bb (1, 1);
I2C_BB_DELAY;
i2c_bb (1, 0);
I2C_BB_DELAY;
i2c_bb (0, 0);
I2C_BB_DELAY;
}
void
i2c_bb_stop (void)
{
i2c_bb (0, 0);
I2C_BB_DELAY;
i2c_bb (1, 0);
I2C_BB_DELAY;
i2c_bb (1, 1);
I2C_BB_DELAY;
}
int
i2c_bb_send_data (uint8_t v)
{
int c;
for (c = 0x80; c; c >>= 1)
{
i2c_bb (0, c & v);
I2C_BB_DELAY;
i2c_bb (1, c & v);
I2C_BB_DELAY;
i2c_bb (0, c & v);
I2C_BB_DELAY;
}
i2c_bb (0, 1);
I2C_BB_DELAY;
i2c_bb (1, 1);
I2C_BB_DELAY;
c = i2c_bb (1, 1);
i2c_bb (0, 1);
return c;
}
int
i2c_bb_start_transaction (uint8_t a, int wnr)
{
int ret;
i2c_bb_start ();
ret = i2c_bb_send_data (a << 1 | ! !(wnr));
return ret;
}
#if 0
void
i2c_bb_scan (void)
{
int i, r;
return;
i2cp_reset ();
printf ("Probing bus\r\n");
for (i = 0; i < 128; ++i)
{
while (i2cp_lock ());
i2cp_start ();
i2cp_abort_start ();
i2cp_stop ();
i2cp_abort_stop ();
r = i2cp_start_transaction (i, I2C_WRITE);
i2cp_stop ();
i2cp_unlock ();
if (!r)
printf ("Found device at address 0x%x\r\n", i);
usart1_drain ();
}
printf ("Done\r\n");
i2cp_reset ();
}
#endif
void
i2c_bb_init (void)
{
gpio_set_mode (GPIO_SCL, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_OPENDRAIN, SCL);
gpio_set_mode (GPIO_SDA, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_OPENDRAIN, SDA);
i2c_bb_start ();
i2c_bb_stop ();
}
#endif
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