mbed library sources
Dependents: frdm_kl05z_gpio_test
Fork of mbed-src by
Diff: targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/i2c_api.c
- Revision:
- 305:1f0269907d8b
- Parent:
- 247:135e3186a638
diff -r 89b9c3a9a045 -r 1f0269907d8b targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/i2c_api.c --- a/targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/i2c_api.c Fri Aug 29 17:15:07 2014 +0100 +++ b/targets/hal/TARGET_STM/TARGET_NUCLEO_F103RB/i2c_api.c Fri Aug 29 20:45:07 2014 +0100 @@ -55,7 +55,13 @@ {NC, NC, 0} }; +int i2c1_inited = 0; +int i2c2_inited = 0; + void i2c_init(i2c_t *obj, PinName sda, PinName scl) { + int timeout; + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + // Determine the I2C to use I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA); I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL); @@ -63,19 +69,25 @@ obj->i2c = (I2CName)pinmap_merge(i2c_sda, i2c_scl); MBED_ASSERT(obj->i2c != (I2CName)NC); - // Enable I2C clock - if (obj->i2c == I2C_1) { + // Enable I2C clock and configure I2C pins if not done before + if ((obj->i2c == I2C_1)&& !i2c1_inited) { + i2c1_inited = 1; RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE); + // Configure I2C pins + pinmap_pinout(scl, PinMap_I2C_SCL); + pin_mode(scl, OpenDrain); + pinmap_pinout(sda, PinMap_I2C_SDA); + pin_mode(sda, OpenDrain); } - if (obj->i2c == I2C_2) { + if ((obj->i2c == I2C_2)&& !i2c2_inited) { + i2c2_inited = 1; RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2, ENABLE); - } - // Configure I2C pins pinmap_pinout(scl, PinMap_I2C_SCL); pin_mode(scl, OpenDrain); pinmap_pinout(sda, PinMap_I2C_SDA); pin_mode(sda, OpenDrain); + } // Reset to clear pending flags if any i2c_reset(obj); @@ -85,10 +97,17 @@ } void i2c_frequency(i2c_t *obj, int hz) { + int timeout; + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); I2C_InitTypeDef I2C_InitStructure; if ((hz != 0) && (hz <= 400000)) { + + // wait before init + timeout = LONG_TIMEOUT; + while((I2C_GetFlagStatus(i2c, I2C_FLAG_BUSY)) && (timeout-- != 0)); + I2C_DeInit(i2c); // I2C configuration @@ -253,6 +272,13 @@ } void i2c_reset(i2c_t *obj) { + I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c); + int timeout; + + // wait before reset + timeout = LONG_TIMEOUT; + while((I2C_GetFlagStatus(i2c, I2C_FLAG_BUSY)) && (timeout-- != 0)); + if (obj->i2c == I2C_1) { RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, ENABLE); RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, DISABLE);