77 lines
2.1 KiB
C++
77 lines
2.1 KiB
C++
|
#include "MicroBit.h"
|
||
|
|
#include "mbed.h"
|
||
|
|
#include "twi_master.h"
|
||
|
|
#include "nrf_delay.h"
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Constructor.
|
||
|
|
* Create an instance of i2c
|
||
|
|
* @param sda the Pin to be used for SDA
|
||
|
|
* @param scl the Pin to be used for SCL
|
||
|
|
* Example:
|
||
|
|
* @code
|
||
|
|
* MicroBitI2C i2c(MICROBIT_PIN_SDA, MICROBIT_PIN_SCL);
|
||
|
|
* @endcode
|
||
|
|
* @note this should prevent i2c lockups as well.
|
||
|
|
*/
|
||
|
|
MicroBitI2C::MicroBitI2C(PinName sda, PinName scl) : I2C(sda,scl)
|
||
|
|
{
|
||
|
|
this->retries = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
int MicroBitI2C::read(int address, char *data, int length, bool repeated)
|
||
|
|
{
|
||
|
|
int result = I2C::read(address,data,length,repeated);
|
||
|
|
|
||
|
|
//0 indicates a success, presume failure
|
||
|
|
while(result != 0 && retries < MICROBIT_I2C_MAX_RETRIES)
|
||
|
|
{
|
||
|
|
_i2c.i2c->EVENTS_ERROR = 0;
|
||
|
|
_i2c.i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
|
||
|
|
_i2c.i2c->POWER = 0;
|
||
|
|
nrf_delay_us(5);
|
||
|
|
_i2c.i2c->POWER = 1;
|
||
|
|
_i2c.i2c->ENABLE = TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos;
|
||
|
|
twi_master_init_and_clear();
|
||
|
|
result = I2C::read(address,data,length,repeated);
|
||
|
|
retries++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if(retries == MICROBIT_I2C_MAX_RETRIES - 1)
|
||
|
|
uBit.panic(MICROBIT_I2C_LOCKUP);
|
||
|
|
|
||
|
|
retries = 0;
|
||
|
|
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
int MicroBitI2C::write(int address, const char *data, int length, bool repeated)
|
||
|
|
{
|
||
|
|
|
||
|
|
|
||
|
|
int result = I2C::write(address,data,length,repeated);
|
||
|
|
|
||
|
|
//0 indicates a success, presume failure
|
||
|
|
while(result != 0 && retries < MICROBIT_I2C_MAX_RETRIES)
|
||
|
|
{
|
||
|
|
_i2c.i2c->EVENTS_ERROR = 0;
|
||
|
|
_i2c.i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
|
||
|
|
_i2c.i2c->POWER = 0;
|
||
|
|
nrf_delay_us(5);
|
||
|
|
_i2c.i2c->POWER = 1;
|
||
|
|
_i2c.i2c->ENABLE = TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos;
|
||
|
|
|
||
|
|
twi_master_init_and_clear();
|
||
|
|
result = I2C::write(address,data,length,repeated);
|
||
|
|
retries++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if(retries == MICROBIT_I2C_MAX_RETRIES - 1)
|
||
|
|
uBit.panic(MICROBIT_I2C_LOCKUP);
|
||
|
|
|
||
|
|
retries = 0;
|
||
|
|
|
||
|
|
return result;
|
||
|
|
}
|