void initI2CModule(void)
{
unsigned int flags = EUSCI_B_I2C_TRANSMIT_INTERRUPT0 |
EUSCI_B_I2C_RECEIVE_INTERRUPT0 |
EUSCI_B_I2C_TRANSMIT_INTERRUPT1 |
EUSCI_B_I2C_RECEIVE_INTERRUPT1 |
EUSCI_B_I2C_STOP_INTERRUPT |
EUSCI_B_I2C_NAK_INTERRUPT;
#if 0
/* Select Port B1 for I2C - Set Pin 4, 5 to input Primary Module Function,
* (UCB1SIMO/UCB1SDA, UCB1SOMI/UCB1SCL).
*/
GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P6,
GPIO_PIN4 + GPIO_PIN5, GPIO_PRIMARY_MODULE_FUNCTION);
/* eUSCI I2C Slave Configuration */
I2C_initSlave(EUSCI_B1_BASE, SLAVE_ADDRESS, EUSCI_B_I2C_OWN_ADDRESS_OFFSET0,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
I2C_initSlave(EUSCI_B1_BASE, 0xC, EUSCI_B_I2C_OWN_ADDRESS_OFFSET1,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
I2C_setMode(EUSCI_B1_BASE, EUSCI_B_I2C_RECEIVE_MODE);
/* Enable the module and enable interrupts */
I2C_enableModule(EUSCI_B1_BASE);
MAP_I2C_clearInterruptFlag(EUSCI_B1_BASE, EUSCI_B_I2C_RECEIVE_INTERRUPT0);
MAP_I2C_enableInterrupt(EUSCI_B1_BASE, EUSCI_B_I2C_RECEIVE_INTERRUPT0);
MAP_Interrupt_enableInterrupt(INT_EUSCIB1);
#else
/* eUSCI I2C Slave Configuration */
I2C_initSlave(EUSCI_B0_BASE, SLAVE_ADDRESS, EUSCI_B_I2C_OWN_ADDRESS_OFFSET0,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
#if 1
I2C_initSlave(EUSCI_B0_BASE, 0xC, EUSCI_B_I2C_OWN_ADDRESS_OFFSET1,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
#endif
/* Select Port B2 for I2C - Set Pin 6, 7 to input Primary Module Function
*/
MAP_GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1,
GPIO_PIN6 | GPIO_PIN7, GPIO_PRIMARY_MODULE_FUNCTION);
/* Define the SMbus alert pin */
MAP_GPIO_setOutputHighOnPin(GPIO_PORT_P5, GPIO_PIN0);
MAP_GPIO_setAsOutputPin(GPIO_PORT_P5, GPIO_PIN0);
I2C_setMode(EUSCI_B0_BASE, EUSCI_B_I2C_RECEIVE_MODE);
/* Enable the module and enable interrupts */
I2C_enableModule(EUSCI_B0_BASE);
MAP_I2C_clearInterruptFlag(EUSCI_B0_BASE, flags);
MAP_Interrupt_setPriority(INT_EUSCIB0, configMAX_SYSCALL_INTERRUPT_PRIORITY);
MAP_I2C_enableInterrupt(EUSCI_B0_BASE, flags);
MAP_Interrupt_enableInterrupt(INT_EUSCIB0);
#endif
}
void DWire::_initSlave( void )
{
// Init the pins
MAP_GPIO_setAsPeripheralModuleFunctionInputPin( modulePort, modulePins,
GPIO_PRIMARY_MODULE_FUNCTION );
// initialise driverlib
MAP_I2C_initSlave( module, slaveAddress, EUSCI_B_I2C_OWN_ADDRESS_OFFSET0,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE );
// Enable the module and enable interrupts
MAP_I2C_enableModule( module );
MAP_I2C_clearInterruptFlag( module,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_STOP_INTERRUPT
| EUSCI_B_I2C_TRANSMIT_INTERRUPT0 | EUSCI_B_I2C_CLOCK_LOW_TIMEOUT_INTERRUPT );
MAP_I2C_enableInterrupt( module,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_STOP_INTERRUPT
| EUSCI_B_I2C_TRANSMIT_INTERRUPT0 | EUSCI_B_I2C_CLOCK_LOW_TIMEOUT_INTERRUPT );
/* Enable the clock low timeout */
EUSCI_B_CMSIS( module )->CTLW1 = (EUSCI_B_CMSIS( module )->CTLW1
& ~EUSCI_B_CTLW1_CLTO_MASK) | 0xC0;
MAP_Interrupt_enableInterrupt( intModule );
MAP_Interrupt_enableMaster( );
}
/**
* Called to set the eUSCI module in 'master' mode
*/
void DWire::_initMaster(const eUSCI_I2C_MasterConfig * i2cConfig) {
// Initialise the pins
MAP_GPIO_setAsPeripheralModuleFunctionInputPin(modulePort, modulePins,
GPIO_PRIMARY_MODULE_FUNCTION);
// Initializing I2C Master to SMCLK at 400kbs with no autostop
MAP_I2C_initMaster(module, i2cConfig);
// Specify slave address
MAP_I2C_setSlaveAddress(module, slaveAddress);
// Set Master in transmit mode
MAP_I2C_setMode(module, EUSCI_B_I2C_TRANSMIT_MODE);
// Enable I2C Module to start operations
MAP_I2C_enableModule(module);
// Enable and clear the interrupt flag
MAP_I2C_clearInterruptFlag(module,
EUSCI_B_I2C_TRANSMIT_INTERRUPT0 + EUSCI_B_I2C_NAK_INTERRUPT
+ EUSCI_B_I2C_RECEIVE_INTERRUPT0);
// Enable master interrupts
MAP_I2C_enableInterrupt(module,
EUSCI_B_I2C_TRANSMIT_INTERRUPT0 + EUSCI_B_I2C_NAK_INTERRUPT
+ EUSCI_B_I2C_RECEIVE_INTERRUPT0);
// Register the interrupts on the correct module
MAP_Interrupt_enableInterrupt(intModule);
MAP_Interrupt_enableMaster();
}
/**
* End the transmission and transmit the tx buffer's contents over the bus
* it returns false if succesful
*/
bool DWire::endTransmission( bool sendStop )
{
// return, if there is nothing to transmit
if (!*pTxBufferIndex)
{
return true;
}
// Wait until any ongoing (incoming) transmissions are finished
timeout = 0xFFFF;
while ( MAP_I2C_masterIsStopSent( module ) == EUSCI_B_I2C_SENDING_STOP
&& timeout)
timeout--;
if (!timeout)
{
/* If we can't start the transmission, then reset everything */
_resetBus( );
return true;
}
this->sendStop = sendStop;
gotNAK = false;
// Clear the interrupt flags and enable
MAP_I2C_clearInterruptFlag( module,
EUSCI_B_I2C_TRANSMIT_INTERRUPT0 + EUSCI_B_I2C_NAK_INTERRUPT );
MAP_I2C_enableInterrupt( module,
EUSCI_B_I2C_TRANSMIT_INTERRUPT0 + EUSCI_B_I2C_NAK_INTERRUPT );
// Set the master into transmit mode
MAP_I2C_setMode( module, EUSCI_B_I2C_TRANSMIT_MODE );
// Send the start condition and initial byte
(*pTxBufferSize) = *pTxBufferIndex;
// Send the first byte, triggering the TX interrupt
MAP_I2C_masterSendMultiByteStartWithTimeout( module, pTxBuffer[0],
TIMEOUTLIMIT );
// make sure the transmitter buffer has been flushed
timeout = TIMEOUTLIMIT;
while (*pTxBufferIndex && timeout)
timeout--;
if (!timeout)
{
_resetBus( );
return true;
}
if (gotNAK)
{
_I2CDelay( );
MAP_I2C_masterReceiveMultiByteStop( module );
}
return gotNAK;
}
/**
* Request data from a SLAVE as a MASTER
*/
uint8_t DWire::requestFrom(uint_fast8_t slaveAddress, uint_fast8_t numBytes) {
// No point of doing anything else if there we're not a MASTER
if (busRole != BUS_ROLE_MASTER)
return 0;
if (*pTxBufferIndex > 0) {
endTransmission(false);
}
while (!sendStop)
;
// Re-initialise the rx buffer
*pRxBufferSize = numBytes;
*pRxBufferIndex = 0;
// Configure the correct slave
MAP_I2C_setSlaveAddress(module, slaveAddress);
this->slaveAddress = slaveAddress;
MAP_I2C_disableInterrupt(module, EUSCI_B_I2C_TRANSMIT_INTERRUPT0);
// Set the master into receive mode
MAP_I2C_setMode(module, EUSCI_B_I2C_RECEIVE_MODE);
// Send the START
MAP_I2C_masterReceiveStart(module);
// Send a stop early if we're only requesting one byte
// to prevent timing issues
if (numBytes == 1) {
MAP_I2C_masterReceiveMultiByteStop(module);
}
// Initialize the flag showing the status of the request
requestDone = false;
gotNAK = false;
// Wait until the request is done
while (!requestDone)
;
MAP_I2C_setMode(module, EUSCI_B_I2C_TRANSMIT_MODE);
MAP_I2C_enableInterrupt(module, EUSCI_B_I2C_TRANSMIT_INTERRUPT0);
MAP_I2C_clearInterruptFlag(module, EUSCI_B_I2C_TRANSMIT_INTERRUPT0);
// Reset the buffer
(*pRxBufferIndex) = 0;
(*pRxBufferSize) = 0;
if (gotNAK) {
return 0;
} else {
return rxReadLength;
}
}
int main(void)
{
uint32_t ii;
/* Disabling the Watchdog */
MAP_WDT_A_holdTimer();
xferIndex = 0;
/* Select Port 1 for I2C - Set Pin 6, 7 to input Primary Module Function,
* (UCB0SIMO/UCB0SDA, UCB0SOMI/UCB0SCL).
*/
MAP_GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1,
GPIO_PIN6 + GPIO_PIN7, GPIO_PRIMARY_MODULE_FUNCTION);
/* Configuring GPIO P1.0 to be an input. As the GPIO is pulled up by the
* master, when the port is set to an input the pull-up defaults and the
* pin is high. When the interrupt is asserted, we set the GPIO to an
* output low and cause the interrupt to occur.
*/
MAP_GPIO_setOutputLowOnPin(GPIO_PORT_P1, GPIO_PIN1);
MAP_GPIO_setAsInputPin(GPIO_PORT_P1, GPIO_PIN0);
/* eUSCI I2C Slave Configuration */
MAP_I2C_initSlave(EUSCI_B0_MODULE, SLAVE_ADDRESS_1, EUSCI_B_I2C_OWN_ADDRESS_OFFSET0,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
/* Enable the module and enable interrupts */
MAP_I2C_enableModule(EUSCI_B0_MODULE);
MAP_Interrupt_enableInterrupt(INT_EUSCIB0);
/* Sleeping while not in use */
while (1)
{
/* Delaying between transactions */
for(ii=0;ii<4000;ii++);
/* Initiating the read from the master by asserting our GPIO */
MAP_I2C_enableInterrupt(EUSCI_B0_MODULE, EUSCI_B_I2C_TRANSMIT_INTERRUPT0);
MAP_GPIO_setAsOutputPin(GPIO_PORT_P1, GPIO_PIN0);
MAP_Interrupt_enableSleepOnIsrExit();
MAP_PCM_gotoLPM0InterruptSafe();
}
}
int main(void)
{
/* Disabling the Watchdog */
MAP_WDT_A_holdTimer();
xferIndex_0 = 0;
xferIndex_1 = 0;
/* Select Port 1 for I2C - Set Pin 6, 7 to input Primary Module Function,
* (UCB0SIMO/UCB0SDA, UCB0SOMI/UCB0SCL).
*/
MAP_GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1,
GPIO_PIN6 + GPIO_PIN7, GPIO_PRIMARY_MODULE_FUNCTION);
/* eUSCI I2C Slave Configuration */
/* Slave Address 1 (0x48) */
MAP_I2C_initSlave(EUSCI_B0_MODULE, SLAVE_ADDRESS_1,
EUSCI_B_I2C_OWN_ADDRESS_OFFSET0,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
/* Slave Address 1 (0x49) */
MAP_I2C_initSlave(EUSCI_B0_MODULE, SLAVE_ADDRESS_2,
EUSCI_B_I2C_OWN_ADDRESS_OFFSET1,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
/* Set in receive mode */
MAP_I2C_setMode(EUSCI_B0_MODULE, EUSCI_B_I2C_RECEIVE_MODE);
/* Enable the module and enable interrupts */
MAP_I2C_enableModule(EUSCI_B0_MODULE);
MAP_I2C_clearInterruptFlag(EUSCI_B0_MODULE,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_RECEIVE_INTERRUPT1);
MAP_I2C_enableInterrupt(EUSCI_B0_MODULE,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_RECEIVE_INTERRUPT1);
MAP_Interrupt_enableSleepOnIsrExit();
MAP_Interrupt_enableInterrupt(INT_EUSCIB0);
MAP_Interrupt_enableMaster();
/* Sleeping while not in use */
while (1)
{
MAP_PCM_gotoLPM0();
}
}
void DWire::_initSlave(void) {
// Init the pins
MAP_GPIO_setAsPeripheralModuleFunctionInputPin(modulePort, modulePins,
GPIO_PRIMARY_MODULE_FUNCTION);
// initialise driverlib
MAP_I2C_initSlave(module, slaveAddress, EUSCI_B_I2C_OWN_ADDRESS_OFFSET0,
EUSCI_B_I2C_OWN_ADDRESS_ENABLE);
// Enable the module
MAP_I2C_enableModule(module);
// Enable the module and enable interrupts
MAP_I2C_enableModule(module);
MAP_I2C_clearInterruptFlag(module,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_STOP_INTERRUPT
| EUSCI_B_I2C_TRANSMIT_INTERRUPT0);
MAP_I2C_enableInterrupt(module,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_STOP_INTERRUPT
| EUSCI_B_I2C_TRANSMIT_INTERRUPT0);
//MAP_Interrupt_enableSleepOnIsrExit();
MAP_Interrupt_enableInterrupt(intModule);
MAP_Interrupt_enableMaster();
}
/**
* Request data from a SLAVE as a MASTER
*/
uint8_t DWire::requestFrom( uint_fast8_t slaveAddress, uint_fast8_t numBytes )
{
// No point of doing anything else if there we're not a MASTER
if (busRole != BUS_ROLE_MASTER)
return 0;
// still something to send? Flush the TX buffer but do not send a STOP
if (*pTxBufferIndex > 0)
{
// this is a repeated start: no point in trying to receive if we fail finishing the transmission
if (endTransmission( false ))
{
return 0;
}
}
else
{
// Wait until any request is finished
timeout = TIMEOUTLIMIT;
while ( MAP_I2C_masterIsStopSent( module ) == EUSCI_B_I2C_SENDING_STOP
&& timeout)
timeout--;
}
if (!timeout)
{
/* If we get a timeout, then reset everything */
_resetBus( );
return 0;
}
// Re-initialise the rx buffer
// and make sure we never request 1 byte only
// this is an anomalous behaviour of the MSP432 related to the double
// buffering of I2C. This is a workaround.
if (numBytes == 1)
{
*pRxBufferSize = 2;
} else
{
*pRxBufferSize = numBytes;
}
*pRxBufferIndex = 0;
// Configure the correct slave
MAP_I2C_setSlaveAddress( module, slaveAddress );
this->slaveAddress = slaveAddress;
MAP_I2C_clearInterruptFlag( module,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_NAK_INTERRUPT );
MAP_I2C_enableInterrupt( module,
EUSCI_B_I2C_RECEIVE_INTERRUPT0 | EUSCI_B_I2C_NAK_INTERRUPT );
// Set the master into receive mode
MAP_I2C_setMode( module, EUSCI_B_I2C_RECEIVE_MODE );
// Initialize the flag showing the status of the request
requestDone = false;
gotNAK = false;
// Send the START
MAP_I2C_masterReceiveStart( module );
// Wait until the request is done
timeout = TIMEOUTLIMIT;
while (!requestDone && timeout)
timeout--;
if (!timeout)
{
/* If we get a timeout, then reset everything */
_resetBus( );
return 0;
}
if (gotNAK)
{
_I2CDelay( );
MAP_I2C_masterReceiveMultiByteStop( module );
return 0;
}
else
{
if (numBytes == 1)
{
return --(*pRxBufferSize);
}
else
{
return *pRxBufferSize;
}
}
}
int main(void)
{
volatile uint32_t ii;
/* Disabling the Watchdog */
MAP_WDT_A_holdTimer();
/* Select Port 1 for I2C - Set Pin 6, 7 to input Primary Module Function,
* (UCB0SIMO/UCB0SDA, UCB0SOMI/UCB0SCL).
*/
MAP_GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1,
GPIO_PIN6 + GPIO_PIN7, GPIO_PRIMARY_MODULE_FUNCTION);
sendStopCondition = false;
sendToSlaveAddress2 = false;
/* Initializing I2C Master to SMCLK at 400kbs with no autostop */
MAP_I2C_initMaster(EUSCI_B0_MODULE, &i2cConfig);
/* Specify slave address. For start we will do our first slave address */
MAP_I2C_setSlaveAddress(EUSCI_B0_MODULE, SLAVE_ADDRESS_1);
/* Set Master in receive mode */
MAP_I2C_setMode(EUSCI_B0_MODULE, EUSCI_B_I2C_TRANSMIT_MODE);
/* Enable I2C Module to start operations */
MAP_I2C_enableModule(EUSCI_B0_MODULE);
/* Enable and clear the interrupt flag */
MAP_I2C_clearInterruptFlag(EUSCI_B0_MODULE,
EUSCI_B_I2C_TRANSMIT_INTERRUPT0 + EUSCI_B_I2C_NAK_INTERRUPT);
//Enable master Receive interrupt
MAP_I2C_enableInterrupt(EUSCI_B0_MODULE,
EUSCI_B_I2C_TRANSMIT_INTERRUPT0 + EUSCI_B_I2C_NAK_INTERRUPT);
MAP_Interrupt_enableInterrupt(INT_EUSCIB0);
while (1)
{
/* Load Byte Counter */
TXByteCtr = 4;
/* Making sure the last transaction has been completely sent out */
while (MAP_I2C_masterIsStopSent(EUSCI_B0_MODULE) == EUSCI_B_I2C_SENDING_STOP);
/* Sending the initial start condition for appropriate
* slave addresses */
if(sendToSlaveAddress2)
{
MAP_I2C_setSlaveAddress(EUSCI_B0_MODULE, SLAVE_ADDRESS_2);
}
else
{
MAP_I2C_setSlaveAddress(EUSCI_B0_MODULE, SLAVE_ADDRESS_1);
}
MAP_I2C_masterSendMultiByteStart(EUSCI_B0_MODULE, TXData++);
while(sendStopCondition == false)
{
/* Go to sleep while data is being transmitted */
MAP_Interrupt_enableSleepOnIsrExit();
MAP_PCM_gotoLPM0InterruptSafe();
}
sendStopCondition = false;
}
}
