/*FUNCTION**********************************************************************
*
* Function Name : I2C_HAL_SlaveSendDataPolling
* Description : Send out multiple bytes of data using polling method.
*
*END*/
i2c_status_t I2C_HAL_SlaveSendDataPolling(I2C_Type * base, const uint8_t* txBuff, uint32_t txSize)
{
#if FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/** Wait until start detected */
while(!I2C_HAL_GetStartFlag(base))
{}
I2C_HAL_ClearStartFlag(base);
#endif
/** Wait until addressed as a slave */
while(!I2C_HAL_GetStatusFlag(base, kI2CAddressAsSlave))
{}
/** Wait interrupt flag is set */
while(!I2C_HAL_IsIntPending(base))
{}
/** Clear interrupt flag */
I2C_HAL_ClearInt(base);
/** Set direction mode */
if (I2C_HAL_GetStatusFlag(base, kI2CSlaveTransmit))
{
/** Switch to TX mode*/
I2C_HAL_SetDirMode(base, kI2CSend);
}
else
{
/** Switch to RX mode.*/
I2C_HAL_SetDirMode(base, kI2CReceive);
/** Read dummy character.*/
I2C_HAL_ReadByte(base);
}
/** While loop to transmit data */
while(txSize--)
{
/** Write byte to data register */
I2C_HAL_WriteByte(base, *txBuff++);
/** Wait tranfer byte complete */
while(!I2C_HAL_IsIntPending(base))
{}
/** Clear interrupt flag */
I2C_HAL_ClearInt(base);
/** if NACK received */
if ((I2C_HAL_GetStatusFlag(base, kI2CReceivedNak)) && (txSize != 0))
{
return kStatus_I2C_ReceivedNak;
}
}
/** Switch to RX mode.*/
I2C_HAL_SetDirMode(base, kI2CReceive);
/** Read dummy character.*/
I2C_HAL_ReadByte(base);
return kStatus_I2C_Success;
}
int i2c_byte_read(i2c_t *obj, int last) {
char data;
uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
// set rx mode
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CReceive);
// Setup read
i2c_do_read(obj, &data, last);
// set tx mode
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
return I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
}
/*FUNCTION**********************************************************************
*
* Function Name : I2C_HAL_SlaveReceiveDataPolling
* Description : Receive multiple bytes of data using polling method.
*
*END*/
i2c_status_t I2C_HAL_SlaveReceiveDataPolling(I2C_Type * base, uint8_t *rxBuff, uint32_t rxSize)
{
#if FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/** Wait until start detected */
while(!I2C_HAL_GetStartFlag(base))
{}
I2C_HAL_ClearStartFlag(base);
#endif
/** Wait until addressed as a slave */
while(!I2C_HAL_GetStatusFlag(base, kI2CAddressAsSlave))
{}
/** Wait interrupt flag is set */
while(!I2C_HAL_IsIntPending(base))
{}
/** Clear interrupt flag */
I2C_HAL_ClearInt(base);
/** Set direction mode */
if (I2C_HAL_GetStatusFlag(base, kI2CSlaveTransmit))
{
/** Switch to TX mode*/
I2C_HAL_SetDirMode(base, kI2CSend);
}
else
{
/** Switch to RX mode.*/
I2C_HAL_SetDirMode(base, kI2CReceive);
/** Read dummy character.*/
I2C_HAL_ReadByte(base);
}
/** While loop to receive data */
while(rxSize--)
{
/** Wait interrupt flag is set */
while(!I2C_HAL_IsIntPending(base))
{}
/** Read byte from data register */
*rxBuff++ = I2C_HAL_ReadByte(base);
/** Clear interrupt flag */
I2C_HAL_ClearInt(base);
}
return kStatus_I2C_Success;
}
int i2c_slave_read(i2c_t *obj, char *data, int length) {
uint8_t dummy_read;
uint8_t *ptr;
int count;
uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
// set rx mode
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
// first dummy read
dummy_read = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
if (i2c_wait_end_rx_transfer(obj))
return 0;
// read address
dummy_read = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
if (i2c_wait_end_rx_transfer(obj))
return 0;
// read (length - 1) bytes
for (count = 0; count < (length - 1); count++) {
data[count] = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
if (i2c_wait_end_rx_transfer(obj))
return count;
}
// read last byte
ptr = (length == 0) ? &dummy_read : (uint8_t *)&data[count];
*ptr = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
return (length) ? (count + 1) : 0;
}
int i2c_byte_write(i2c_t *obj, int data) {
uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
// set tx mode
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
return !i2c_do_write(obj, (data & 0xFF));
}
//
// Originally, 'endTransmission' was an f(void) function.
// It has been modified to take one parameter indicating
// whether or not a STOP should be performed on the bus.
// Calling endTransmission(false) allows a sketch to
// perform a repeated start.
//
// WARNING: Nothing in the library keeps track of whether
// the bus tenure has been properly ended with a STOP. It
// is very possible to leave the bus in a hung state if
// no call to endTransmission(true) is made. Some I2C
// devices will behave oddly if they do not see a STOP.
//
uint8_t TwoWire::endTransmission(uint8_t sendStop)
{
/* Set direction to send for sending of address and data. */
uint8_t result = (uint8_t)getWriteError();
if(result != 0)
{
// reset tx buffer iterator vars
txBufferIndex = 0;
txBufferLength = 0;
// indicate that we are done transmitting
transmitting_master = false;
return 1;
}
uint32_t t0 = millis();
while(I2C_HAL_GetStatusFlag(instance, kI2CBusBusy) && !I2C_HAL_IsMaster(instance))
{
if(millis() - t0 >= 25)
return 4; //timeout
}
uint16_t slaveAddress;
slaveAddress = (txAddress << 1U) & 0x00FFU;
bool sent = sendAddress(slaveAddress);
//tx buffer also sent by interrupt
// reset tx buffer iterator vars
txBufferIndex = 0;
txBufferLength = 0;
// indicate that we are done transmitting
transmitting_master = false;
clearWriteError();
result = 4;
if(sent) //sent without timeout
{
if(master_state == MASTER_STATE_COMPLETE)
{
result = 0;
}
else if(master_state == MASTER_STATE_TX_NAK) //failed
{
result = (txBufferIndex == 0) ? 2 : 3; //address or data fail
sendStop = true;
}
if(sendStop)
{
I2C_HAL_SendStop(instance);
}
}
I2C_HAL_SetDirMode(instance, kI2CReceive);
return result;
}
int i2c_slave_write(i2c_t *obj, const char *data, int length) {
int i, count = 0;
uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
// set tx mode
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CSend);
for (i = 0; i < length; i++) {
if (i2c_do_write(obj, data[count++]) == 2)
return i;
}
// set rx mode
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CReceive);
// dummy rx transfer needed
// otherwise the master cannot generate a stop bit
I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
if (i2c_wait_end_rx_transfer(obj) == 2)
return count;
return count;
}
bool TwoWire::sendAddress(uint16_t slaveAddress)
{
master_state = MASTER_STATE_IDLE;
I2C_HAL_SetDirMode(instance, kI2CSend);
if(master_send_stop)
I2C_HAL_SendStart(instance);
I2C_HAL_WriteByte(instance, slaveAddress);
uint32_t t0 = millis();
while(master_state == MASTER_STATE_IDLE || master_state == MASTER_STATE_ARB_LOST)
{
if(millis() - t0 >= 25 || master_state == MASTER_STATE_ARB_LOST)
{
I2C_HAL_SendStop(instance);
I2C_HAL_SetDirMode(instance, kI2CReceive);
return false; //timeout
}
}
return true;
}
/*FUNCTION**********************************************************************
*
* Function Name : I2C_DRV_SlaveReceiveData
* Description : Receive the data using a non-blocking method.
* This function set buffer pointer and length to Rx buffer & Rx Size
* A non-blocking (also known as synchronous) function means that the function
* returns immediately after initiating the receive function. The application
* has to get the receive status to see when the receive is complete.
*
*END**************************************************************************/
i2c_status_t I2C_DRV_SlaveReceiveData(uint32_t instance,
uint8_t * rxBuff,
uint32_t rxSize)
{
assert(rxBuff);
assert(instance < HW_I2C_INSTANCE_COUNT);
i2c_slave_state_t * i2cSlaveState = (i2c_slave_state_t *)g_i2cStatePtr[instance];
if(!i2cSlaveState->slaveListening)
{
if (i2cSlaveState->isRxBusy)
{
return kStatus_I2C_Busy;
}
i2cSlaveState->rxBuff = rxBuff;
i2cSlaveState->rxSize = rxSize;
i2cSlaveState->isRxBusy = true;
/* If IAAS event already comes, read dummy to release the bus.*/
if(I2C_HAL_GetStatusFlag(g_i2cBaseAddr[instance], kI2CAddressAsSlave))
{
/* Switch to RX mode.*/
I2C_HAL_SetDirMode(g_i2cBaseAddr[instance], kI2CReceive);
I2C_HAL_ReadByte(g_i2cBaseAddr[instance]);
}
#if FSL_FEATURE_I2C_HAS_START_STOP_DETECT
I2C_HAL_ClearStartFlag(g_i2cBaseAddr[instance]);
#endif
I2C_HAL_ClearInt(g_i2cBaseAddr[instance]);
I2C_HAL_SetIntCmd(g_i2cBaseAddr[instance], true);
return kStatus_I2C_Success;
}
else /* i2cSlaveState->slaveListening */
{
return kStatus_I2C_Fail;
}
}
int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
int count;
char dummy_read, *ptr;
if (i2c_start(obj)) {
i2c_stop(obj);
return I2C_ERROR_BUS_BUSY;
}
if (i2c_do_write(obj, (address | 0x01))) {
i2c_stop(obj);
return I2C_ERROR_NO_SLAVE;
}
// set rx mode
uint32_t i2c_addrs[] = I2C_BASE_ADDRS;
I2C_HAL_SetDirMode(i2c_addrs[obj->instance], kI2CReceive);
// Read in bytes
for (count = 0; count < (length); count++) {
ptr = (count == 0) ? &dummy_read : &data[count - 1];
uint8_t stop_ = (count == (length - 1)) ? 1 : 0;
if (i2c_do_read(obj, ptr, stop_)) {
i2c_stop(obj);
return count;
}
}
// If not repeated start, send stop.
if (stop)
i2c_stop(obj);
// last read
data[count-1] = I2C_HAL_ReadByte(i2c_addrs[obj->instance]);
return length;
}
/*FUNCTION**********************************************************************
*
* Function Name : I2C_DRV_SlaveIRQHandler
* Description : I2C Slave Generic ISR.
* ISR action be called inside I2C IRQ handler entry.
*
*END*/
void I2C_DRV_SlaveIRQHandler(uint32_t instance)
{
assert(instance < I2C_INSTANCE_COUNT);
I2C_Type * base = g_i2cBase[instance];
uint8_t i2cData = 0x00;
bool doTransmit = false;
bool wasArbLost = I2C_HAL_GetStatusFlag(base, kI2CArbitrationLost);
bool addressed = I2C_HAL_GetStatusFlag(base, kI2CAddressAsSlave);
bool stopIntEnabled = false;
#if FSL_FEATURE_I2C_HAS_START_STOP_DETECT
bool startDetected = I2C_HAL_GetStartFlag(base);
bool startIntEnabled = I2C_HAL_GetStartStopIntCmd(base);
bool stopDetected = I2C_HAL_GetStopFlag(base);
stopIntEnabled = startIntEnabled;
#endif
#if FSL_FEATURE_I2C_HAS_STOP_DETECT
bool stopDetected = I2C_HAL_GetStopFlag(base);
stopIntEnabled = I2C_HAL_GetStopIntCmd(base);
#endif
/** Get current runtime structure */
i2c_slave_state_t * i2cSlaveState = (i2c_slave_state_t *)g_i2cStatePtr[instance];
/** Get current slave transfer direction */
i2c_direction_t direction = I2C_HAL_GetDirMode(base);
#if FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/*--------------- Handle START ------------------*/
if (startIntEnabled && startDetected)
{
I2C_HAL_ClearStartFlag(base);
I2C_HAL_ClearInt(base);
if(i2cSlaveState->slaveCallback != NULL)
{
/*Call callback to handle when the driver detect START signal*/
i2cSlaveState->slaveCallback(instance,
kI2CSlaveStartDetect,
i2cSlaveState->callbackParam);
}
return;
}
#endif
#if FSL_FEATURE_I2C_HAS_START_STOP_DETECT || FSL_FEATURE_I2C_HAS_STOP_DETECT
/*--------------- Handle STOP ------------------*/
if (stopIntEnabled && stopDetected)
{
I2C_HAL_ClearStopFlag(base);
I2C_HAL_ClearInt(base);
if(!i2cSlaveState->slaveListening)
{
/** Disable I2C interrupt in the peripheral.*/
I2C_HAL_SetIntCmd(base, false);
}
if(i2cSlaveState->slaveCallback != NULL)
{
/*Call callback to handle when the driver detect STOP signal*/
i2cSlaveState->slaveCallback(instance,
kI2CSlaveStopDetect,
i2cSlaveState->callbackParam);
}
if (i2cSlaveState->isRxBlocking)
{
OSA_EventSet(&i2cSlaveState->irqEvent, kI2CSlaveStopDetect);
}
i2cSlaveState->status = kStatus_I2C_Idle;
return;
}
#endif
/** Clear I2C IRQ.*/
I2C_HAL_ClearInt(base);
if (wasArbLost)
{
I2C_HAL_ClearArbitrationLost(base);
if (!addressed)
{
i2cSlaveState->status = kStatus_I2C_AribtrationLost;
if(!i2cSlaveState->slaveListening)
{
/** Disable I2C interrupt in the peripheral.*/
I2C_HAL_SetIntCmd(base, false);
}
return;
}
}
/*--------------- Handle Address ------------------*/
/** Addressed only happens when receiving address. */
if (addressed) /** Slave is addressed. */
{
/** Master read from Slave. Slave transmit.*/
if (I2C_HAL_GetStatusFlag(base, kI2CSlaveTransmit))
{
/** Switch to TX mode*/
I2C_HAL_SetDirMode(base, kI2CSend);
if(i2cSlaveState->slaveCallback != NULL)
{
/*Call callback to handle when the driver get read request*/
i2cSlaveState->slaveCallback(instance,
kI2CSlaveTxReq,
i2cSlaveState->callbackParam);
}
doTransmit = true;
}
else /** Master write to Slave. Slave receive.*/
{
/** Switch to RX mode.*/
I2C_HAL_SetDirMode(base, kI2CReceive);
if(i2cSlaveState->slaveCallback != NULL)
{
/*Call callback to handle when the driver get write request*/
i2cSlaveState->slaveCallback(instance,
kI2CSlaveRxReq,
i2cSlaveState->callbackParam);
}
/** Read dummy character.*/
I2C_HAL_ReadByte(base);
}
}
/*--------------- Handle Transfer ------------------*/
else
{
/** Handle transmit */
if (direction == kI2CSend)
{
if (I2C_HAL_GetStatusFlag(base, kI2CReceivedNak))
{
/** Switch to RX mode.*/
I2C_HAL_SetDirMode(base, kI2CReceive);
/** Read dummy character to release bus */
I2C_HAL_ReadByte(base);
if ((!i2cSlaveState->slaveListening) && (!stopIntEnabled))
{
/** Disable I2C interrupt in the peripheral.*/
I2C_HAL_SetIntCmd(base, false);
}
if(i2cSlaveState->slaveCallback != NULL)
{
/** Receive TX NAK, mean transaction is finished, call callback to handle */
i2cSlaveState->slaveCallback(instance,
kI2CSlaveTxNAK,
i2cSlaveState->callbackParam);
}
if (i2cSlaveState->isTxBlocking)
{
OSA_EventSet(&i2cSlaveState->irqEvent, kI2CSlaveTxNAK);
}
i2cSlaveState->txSize = 0;
i2cSlaveState->txBuff = NULL;
i2cSlaveState->isTxBusy = false;
}
else /** ACK from receiver.*/
{
doTransmit = true;
}
}
/** Handle receive */
else
{
/** Get byte from data register */
i2cData = I2C_HAL_ReadByte(base);
if (i2cSlaveState->rxSize)
{
*(i2cSlaveState->rxBuff) = i2cData;
++ i2cSlaveState->rxBuff;
-- i2cSlaveState->rxSize;
if (!i2cSlaveState->rxSize)
{
if (!stopIntEnabled)
{
if(!i2cSlaveState->slaveListening)
{
/** Disable I2C interrupt in the peripheral.*/
I2C_HAL_SetIntCmd(base, false);
}
/** All bytes are received, so we're done with this transfer */
if (i2cSlaveState->isRxBlocking)
{
OSA_EventSet(&i2cSlaveState->irqEvent, kI2CSlaveRxFull);
}
}
i2cSlaveState->isRxBusy = false;
i2cSlaveState->rxBuff = NULL;
if(i2cSlaveState->slaveCallback != NULL)
{
/** Rx buffer is full, call callback to handle */
i2cSlaveState->slaveCallback(instance,
kI2CSlaveRxFull,
i2cSlaveState->callbackParam);
}
}
}
else
{
/** The Rxbuff is full --> Set kStatus_I2C_SlaveRxOverrun*/
i2cSlaveState->status = kStatus_I2C_SlaveRxOverrun;
}
}
}
/** DO TRANSMIT*/
if (doTransmit)
{
/** Send byte to data register */
if (i2cSlaveState->txSize)
{
i2cData = *(i2cSlaveState->txBuff);
I2C_HAL_WriteByte(base, i2cData);
++ i2cSlaveState->txBuff;
-- i2cSlaveState->txSize;
if (!i2cSlaveState->txSize)
{
/** All bytes are received, so we're done with this transfer */
i2cSlaveState->txBuff = NULL;
i2cSlaveState->isTxBusy = false;
if(i2cSlaveState->slaveCallback != NULL)
{
/** Tx buffer is empty, finish transaction, call callback to handle */
i2cSlaveState->slaveCallback(instance,
kI2CSlaveTxEmpty,
i2cSlaveState->callbackParam);
}
}
}
else
{
/** The Txbuff is empty --> set kStatus_I2C_SlaveTxUnderrun*/
i2cSlaveState->status = kStatus_I2C_SlaveTxUnderrun ;
}
}
}
/*FUNCTION**********************************************************************
*
* Function Name : I2C_DRV_SlaveReceiveDataBlocking
* Description : Receive the data using a blocking method.
* This function set buffer pointer and length to Rx buffer &Rx Size. Then wait
* until the transmission is end (all data are received or STOP signal is
* detected)
*
*END*/
i2c_status_t I2C_DRV_SlaveReceiveDataBlocking(uint32_t instance,
uint8_t * rxBuff,
uint32_t rxSize,
uint32_t timeout_ms)
{
assert(rxBuff);
assert(instance < I2C_INSTANCE_COUNT);
i2c_slave_state_t * i2cSlaveState = (i2c_slave_state_t *)g_i2cStatePtr[instance];
if(!i2cSlaveState->slaveListening)
{
event_flags_t i2cIrqSetFlags;
osa_status_t syncStatus;
if (i2cSlaveState->isRxBusy)
{
return kStatus_I2C_Busy;
}
i2cSlaveState->rxBuff = rxBuff;
i2cSlaveState->rxSize = rxSize;
i2cSlaveState->isRxBusy = true;
i2cSlaveState->isRxBlocking = true;
/** If IAAS event already comes, read dummy to release the bus.*/
if(I2C_HAL_GetStatusFlag(g_i2cBase[instance], kI2CAddressAsSlave))
{
/** Switch to RX mode.*/
I2C_HAL_SetDirMode(g_i2cBase[instance], kI2CReceive);
I2C_HAL_ReadByte(g_i2cBase[instance]);
}
I2C_HAL_SetIntCmd(g_i2cBase[instance], true);
/** Wait until the transmit is complete. */
do
{
syncStatus = OSA_EventWait(&i2cSlaveState->irqEvent,
#if (FSL_FEATURE_I2C_HAS_START_STOP_DETECT || FSL_FEATURE_I2C_HAS_STOP_DETECT)
kI2CSlaveStopDetect |
#endif
kI2CSlaveRxFull | kI2CSlaveAbort,
false,
timeout_ms,
&i2cIrqSetFlags);
} while(syncStatus == kStatus_OSA_Idle);
if (syncStatus != kStatus_OSA_Success)
{
I2C_HAL_SetIntCmd(g_i2cBase[instance], false);
i2cSlaveState->status = kStatus_I2C_Timeout;
}
i2cSlaveState->isRxBlocking = false;
return i2cSlaveState->status;
}
else /** i2cSlaveState->slaveListening */
{
return kStatus_I2C_Fail;
}
}
void TwoWire::onService(void)
{
//interrupt handler
uint8_t i2cData = 0x00;
bool wasArbLost = I2C_HAL_GetStatusFlag(instance, kI2CArbitrationLost);
bool addressed = I2C_HAL_GetStatusFlag(instance, kI2CAddressAsSlave);
bool stopIntEnabled = false;
bool startDetected = I2C_HAL_GetStartFlag(instance);
bool startIntEnabled = I2C_HAL_GetStartStopIntCmd(instance);
bool stopDetected = I2C_HAL_GetStopFlag(instance);
stopIntEnabled = startIntEnabled;
/* Get current slave transfer direction */
i2c_direction_t direction = I2C_HAL_GetDirMode(instance);
/*--------------- Handle START, STOP or REPEAT START ------------------*/
if (stopIntEnabled && (startDetected || stopDetected))
{
if(startDetected)
I2C_HAL_ClearStartFlag(instance);
if(stopDetected)
I2C_HAL_ClearStopFlag(instance);
I2C_HAL_ClearInt(instance);
if(slaveBufferLength)
{
if(onReceiveCallback)
{
receiving_slave = true;
onReceiveCallback(slaveBufferLength);
receiving_slave = false;
}
slaveBufferIndex = 0;
slaveBufferLength = 0;
}
return;
}
/* Clear I2C IRQ.*/
I2C_HAL_ClearInt(instance);
if (wasArbLost)
{
I2C_HAL_ClearArbitrationLost(instance);
if (!addressed)
{
master_state = MASTER_STATE_ARB_LOST;
return;
}
}
if(I2C_HAL_IsMaster(instance))
{
if (direction == kI2CSend)
{
//check for NAK
/* Check whether we got an ACK or NAK from the former byte we sent */
if (I2C_HAL_GetStatusFlag(instance, kI2CReceivedNak))
{
master_state = MASTER_STATE_TX_NAK;
}
else if(transmitting_master)
{
/* Continue send if still have data. TxSize/txBuff index need
* increment first because one byte is already sent in order
* to trigger interrupt */
if (txBufferIndex < txBufferLength)
{
/* Transmit next byte and update buffer index */
I2C_HAL_WriteByte(instance, txBuffer[txBufferIndex++]);
}
else
{
/* Finish send data, send STOP, disable interrupt */
master_state = MASTER_STATE_COMPLETE;
}
}
else
{
master_state = MASTER_STATE_READ_READY; //address sent for a read
}
}
else
{
switch (--rxBufferQuantity)
{
case 0x0U:
/* Finish receive data, send STOP, disable interrupt */
master_state = MASTER_STATE_COMPLETE;
if(master_send_stop)
I2C_HAL_SendStop(instance);
else
I2C_HAL_SendStart(instance);
break;
case 0x1U:
/* For the byte before last, we need to set NAK */
I2C_HAL_SendNak(instance);
break;
default :
I2C_HAL_SendAck(instance);
break;
}
rxBuffer[rxBufferLength++] = I2C_HAL_ReadByte(instance);
}
return;
}
/*--------------- Handle Address ------------------*/
/* Addressed only happens when receiving address. */
if (addressed) /* Slave is addressed. */
{
/* Master read from Slave. Slave transmit.*/
if (I2C_HAL_GetStatusFlag(instance, kI2CSlaveTransmit))
{
/* Switch to TX mode*/
I2C_HAL_SetDirMode(instance, kI2CSend);
transmitting_slave = true;
slaveBufferIndex = 0;
slaveBufferLength = 0;
if (onRequestCallback)
onRequestCallback(); //this needs to load the transmit buffer
else
// create a default 1-byte response
write((uint8_t) 0);
}
else /* Master write to Slave. Slave receive.*/
{
/* Switch to RX mode.*/
I2C_HAL_SetDirMode(instance, kI2CReceive);
I2C_HAL_SendAck(instance);
/* Read dummy character.*/
I2C_HAL_ReadByte(instance);
slaveBufferIndex = 0;
slaveBufferLength = 0;
}
}
/*--------------- Handle Transfer ------------------*/
else
{
/* Handle transmit */
if (direction == kI2CSend)
{
if (I2C_HAL_GetStatusFlag(instance, kI2CReceivedNak))
{
/* Switch to RX mode.*/
I2C_HAL_SetDirMode(instance, kI2CReceive);
/* Read dummy character to release bus */
I2C_HAL_ReadByte(instance);
transmitting_slave = false;
slaveBufferIndex = 0;
slaveBufferLength = 0;
}
else /* ACK from receiver.*/
{
transmitting_slave = true;
}
}
/* Handle receive */
else
{
/* Get byte from data register */
I2C_HAL_SendAck(instance);
i2cData = I2C_HAL_ReadByte(instance);
if(slaveBufferLength < BUFFER_LENGTH)
slaveBuffer[slaveBufferLength++] = i2cData;
}
}
if (transmitting_slave)
{
/* Send byte to data register */
if (slaveBufferIndex < slaveBufferLength)
{
I2C_HAL_WriteByte(instance, slaveBuffer[slaveBufferIndex++]);
if (slaveBufferIndex >= slaveBufferLength)
{
slaveBufferIndex = 0;
slaveBufferLength = 0;
transmitting_slave = false;
}
}
else
transmitting_slave = false;
}
}
uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint8_t sendStop)
{
if(quantity == 0) return 0;
uint32_t t0 = millis();
while(I2C_HAL_GetStatusFlag(instance, kI2CBusBusy) && !I2C_HAL_IsMaster(instance))
{
if(millis() - t0 >= 25)
return 4; //timeout
}
if(quantity > BUFFER_LENGTH){
quantity = BUFFER_LENGTH;
}
rxBufferQuantity = quantity;
rxBufferIndex = 0;
rxBufferLength = 0;
uint16_t slaveAddr = (address << 1U) | 1;
if(!sendAddress(slaveAddr) || master_state != MASTER_STATE_READ_READY)
{
I2C_HAL_SendStop(instance);
I2C_HAL_SetDirMode(instance, kI2CReceive);
return 0;
}
master_send_stop = sendStop;
master_state = MASTER_STATE_IDLE;
I2C_HAL_SetDirMode(instance, kI2CReceive);
/* Send NAK if only one byte to read. */
if (rxBufferQuantity == 0x1U)
{
I2C_HAL_SendNak(instance);
}
else
{
I2C_HAL_SendAck(instance);
}
I2C_HAL_ReadByte(instance);
t0 = millis();
while(master_state == MASTER_STATE_IDLE)
{
if(millis() - t0 >= 25)
{
rxBufferIndex = 0;
rxBufferLength = 0;
I2C_HAL_SendStop(instance);
I2C_HAL_SetDirMode(instance, kI2CReceive);
return 0; //timeout
}
}
if(master_state == MASTER_STATE_COMPLETE)
{
rxBufferIndex = 0;
return rxBufferLength;
}
else
{
rxBufferIndex = 0;
rxBufferLength = 0;
rxBufferQuantity = 0;
I2C_HAL_SendStop(instance);
I2C_HAL_SetDirMode(instance, kI2CReceive);
return 0; //timeout
}
}
/*FUNCTION**********************************************************************
*
* Function Name : I2C_HAL_MasterSendDataPolling
* Description : Performs a polling send transaction on the I2C bus.
*
*END*/
i2c_status_t I2C_HAL_MasterSendDataPolling(I2C_Type * base,
uint16_t slaveAddr,
const uint8_t * cmdBuff,
uint32_t cmdSize,
const uint8_t * txBuff,
uint32_t txSize)
{
uint16_t slaveAddress;
slaveAddress = (slaveAddr << 1U) & 0x00FFU;
/** Return if current I2C is already set as master. */
if (I2C_BRD_C1_MST(base))
{
return kStatus_I2C_Busy;
}
/** Set direction to send. */
I2C_HAL_SetDirMode(base, kI2CSend);
/** Generate START signal. */
I2C_HAL_SendStart(base);
/** Send slave address */
if (!I2C_HAL_WriteByteBlocking(base, slaveAddress))
{
/** Send STOP if no ACK received */
I2C_HAL_SendStop(base);
return kStatus_I2C_ReceivedNak;
}
/** Send CMD buffer */
if (cmdBuff != NULL)
{
while (cmdSize--)
{
if (!I2C_HAL_WriteByteBlocking(base, *cmdBuff--))
{
/** Send STOP if no ACK received */
I2C_HAL_SendStop(base);
return kStatus_I2C_ReceivedNak;
}
}
}
/** Send data buffer */
while (txSize--)
{
if (!I2C_HAL_WriteByteBlocking(base, *txBuff++))
{
/** Send STOP if no ACK received */
I2C_HAL_SendStop(base);
return kStatus_I2C_ReceivedNak;
}
}
/** Generate STOP signal. */
I2C_HAL_SendStop(base);
/** Set direction back to receive. */
I2C_HAL_SetDirMode(base, kI2CReceive);
return kStatus_I2C_Success;
}
/*FUNCTION**********************************************************************
*
* Function Name : I2C_HAL_MasterReceiveDataPolling
* Description : Performs a polling receive transaction on the I2C bus.
*
*END*/
i2c_status_t I2C_HAL_MasterReceiveDataPolling(I2C_Type * base,
uint16_t slaveAddr,
const uint8_t * cmdBuff,
uint32_t cmdSize,
uint8_t * rxBuff,
uint32_t rxSize)
{
int32_t i;
uint8_t directionBit, address;
/** Return if current I2C is already set as master. */
if (I2C_BRD_C1_MST(base))
{
return kStatus_I2C_Busy;
}
/** Get r/w bit according to CMD buffer setting
* read is 1, write is 0. */
directionBit = (cmdBuff) ? 0x0U : 0x1U;
address = (uint8_t)slaveAddr << 1U;
/** Set direction to send */
I2C_HAL_SetDirMode(base, kI2CSend);
/** Generate START signal. */
I2C_HAL_SendStart(base);
/** Send slave address */
if (!I2C_HAL_WriteByteBlocking(base, address | directionBit))
{
/** Send STOP if no ACK received */
I2C_HAL_SendStop(base);
return kStatus_I2C_ReceivedNak;
}
/** Send CMD buffer */
if (cmdBuff != NULL)
{
while (cmdSize--)
{
if (!I2C_HAL_WriteByteBlocking(base, *cmdBuff--))
{
/** Send STOP if no ACK received */
I2C_HAL_SendStop(base);
return kStatus_I2C_ReceivedNak;
}
}
/** Need to generate a repeat start before changing to receive. */
I2C_HAL_SendStart(base);
/** Send slave address again */
if (!I2C_HAL_WriteByteBlocking(base, address | 1U))
{
/** Send STOP if no ACK received */
I2C_HAL_SendStop(base);
return kStatus_I2C_ReceivedNak;
}
}
/** Change direction to receive. */
I2C_HAL_SetDirMode(base, kI2CReceive);
/** Send NAK if only one byte to read. */
if (rxSize == 0x1U)
{
I2C_HAL_SendNak(base);
}
else
{
I2C_HAL_SendAck(base);
}
/** Dummy read to trigger receive of next byte. */
I2C_HAL_ReadByteBlocking(base);
/** Receive data */
for(i=rxSize-1; i>=0; i--)
{
switch (i)
{
case 0x0U:
/** Generate STOP signal. */
I2C_HAL_SendStop(base);
break;
case 0x1U:
/** For the byte before last, we need to set NAK */
I2C_HAL_SendNak(base);
break;
default :
I2C_HAL_SendAck(base);
break;
}
/** Read recently received byte into buffer and update buffer index */
if (i==0)
{
*rxBuff++ = I2C_HAL_ReadByte(base);
}
else
{
*rxBuff++ = I2C_HAL_ReadByteBlocking(base);
}
}
return kStatus_I2C_Success;
}